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Engine Specific Info and Questions => mTDI Mechanical TDI Conversions => Topic started by: Zeitgeist on March 24, 2018, 06:42:48 pm

Title: Very little boost on my mTDI ALH Vanagon install
Post by: Zeitgeist on March 24, 2018, 06:42:48 pm
I just got my ALH install completed in the last week, but even though it starts and runs very well, it just won't produce any boost above about 3.5psi.  The power output is on par with what I imagine an NA 1.9L diesel would provide, which is adequate around town, but woefully not up to the task on hills or the freeway. 

Here's a pic:

(https://www.thesamba.com/vw/gallery/pix/1760828.jpg)

The turbo is a k14 from a 3.0L OM606 that's going into my '87 300TD and only has about 74k on it.  The intake is a very short run, and in fact much shorter than the MB donor.  I've checked the wastegate preload (it's a pressure actuator) and ensured that the wheel turns freely with no wobble.  I was expecting the turbo to be laggy, but not to fail to produce any appreciable boost.  I'm kinda at a loss here.  Thoughts?
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: Zeitgeist on March 24, 2018, 08:38:52 pm
I should mention that this is a pump from a RR 300TD--11mm head. 

The engine is from an '01 Jetta automatic, and still has the stock injectors. 
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: libbydiesel on March 25, 2018, 12:16:07 am
The difference between 3.0l and 1.9l is fairly dramatic and the exhaust flow and consequently boost would be proportional.  Do you have EGT gauge installed?  If EGTs/smoke are not unreasonable I would increase the max fuel.  More fuel = more heat = more boost.
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: Zeitgeist on March 25, 2018, 01:09:17 pm
Thanks.  I'll work on finalizing the aux. gauge cluster install today and report back.  The wiring is run up front, but the cluster isn't connected yet.  I'll also do some research on how to turn up the fuel on a VE pump.  I've only done that on inline MB pumps in the past.   
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: libbydiesel on March 25, 2018, 04:51:42 pm
(https://i.imgur.com/FQnVBia.jpg)

Max fuel screw is circled in red.  It should have a 13mm locknut on it.  The fuel stop solenoid is really easy to touch with the wrench and is typically an unfused circuit, so having the key off is wise.  Turn the max fuel screw in CW to increase fuel.  It is quite sensitive.  1/8th turn is noticeable.  After increasing max fuel you might need to lower idle. 
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: Zeitgeist on March 25, 2018, 07:37:59 pm
Thanks, I assume I'll need to remove the crimped collar on that bolt, correct?  Is there a preferred method for removing this without buggering up the threads?
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: libbydiesel on March 25, 2018, 09:33:09 pm
There's usually a bit of added adjustment available before removing the collar but for a significant change, it will need to be removed.  It is actually tack welded on, so the threads are already buggered at the welds.  :-(  The easiest way I've found to remove the collars is to use a sharp punch right between the collar and the bolt inline with one of the tack welds.  It will usually crack the weld.  Then pliers to pull it off.  Usually there is still more than plenty of adjustment available even before the buggered threads come into play with the locknut.
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: libbydiesel on March 25, 2018, 09:35:02 pm
Two coolant pressure tanks?
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: Zeitgeist on March 25, 2018, 11:26:07 pm
Thanks for all the helpful advice.  You were instrumental in assisting me to set up the pump.  The second tank is for the intercooler.  There are two heat exchangers sitting up under the floor on the driver side.  The grey box under the package tray contains the relays for the pump and fan...and glow relay.

Other than the low power issue, I'm really pleased with how well this install has performed.  And with the exception of a few coolant leaks due to inattentive oversights, everything seems to work as designed. The intake is noisy, but the exhaust is fairly quiet.  I wired up the gauges today, but didn't have a chance to drive it yet.         
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: libbydiesel on March 26, 2018, 12:19:02 am
Ah, intercooler.  Of course.  Glad to hear you got it running.  I'm sure you will get the boost issue resolved one way or another.  Not to be a Debbie Downer, but it might take a different turbo, though.  More fuel will make the larger turbo spool faster but you might end up seeing excessive smoke and overly high EGTs before you get it where you would like it to be.  I'll keep my fingers crossed.  Keep posting progress.   
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: Zeitgeist on March 26, 2018, 01:21:45 pm
Yeah, with this budget build it was the only turbo I had on hand.  I think the K14 was used on other small displacement VAG diesels, so I thought maybe I could get away with running it.  The only other turbo I have is a T3, and I assume that's way too large for this setup. 
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: libbydiesel on March 26, 2018, 02:02:57 pm
There was a K14 that was used on the VW 1.6TD and 1.9TD AAZ engines, but it is much smaller than the K14 used on the Merz 3.0L engines.  The same is true for the T3.  If you have one that was used on the VW 1.6TD engine then it would be appropriate for an ALH.  If it is off a 3.0L Merz, then it will likely be too large.  Before turbo shopping, though, start with getting an EGT gauge hooked up and adding more fuel and see how that goes. 
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: Zeitgeist on March 29, 2018, 09:12:06 pm
Well, I've turned up the pump about a quarter turn, and I definitely get more power, but no boost and just a little smoke.  I'm still having some issues with my aux. gauges, so I've just got the coolant temp and oil pressure gauges to guide me at this point.  Under sustained load the boost rises to maybe 3psi, but there's no corresponding rise in coolant temp.  My gut says that the turbo is just too large for the displacement.  My friend gave me a junk K03 knock-off to use as a template for an adapter, and it's quite a bit smaller than this turbo.  I've done some research and it seems that the K03 or a K03/K04 hybrid are my easiest to acquire wastegate-type turbos.  Is that my best bet?  I'm still on a rather constrained budget, so optimal is probably not in the cards. 
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: libbydiesel on March 29, 2018, 10:37:55 pm
If you get the matching manifold as well, you could run any of the wastegated turbos from the AAZ or mk3 TDI's.  My preference is for the AAZ K14.  It's a little larger and has a little more lag than the K03, T2, GT15 but has better top end power and is small enough to boost fairly quickly.  The K24 or T3 from a 1.6TD with matching manifold would be reasonable on an ALH, but are larger than my preference.  My concern with any of them would be fitment with your intake.

Another option would be to run a VNT15 with stationary vanes and fit an external wastegate to the EGR port.  You can then dial in the desired 'size' of the turbo by adjusting the fixed point of the vanes.
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: Zeitgeist on March 30, 2018, 01:58:01 am
I wonder if my 12MM 4BT pump head would make up the difference in fueling needed for this turbo.   
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: libbydiesel on March 30, 2018, 01:38:44 pm
I imagine you can make it smoke and have high EGTs with the LR pump.  If it smokes/has high egts before the turbo is producing decent boost, swapping pumps is not going to fix that situation.
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: Zeitgeist on March 30, 2018, 06:39:55 pm
I was just referring to swapping the 4BT head over to the LR pump.  But, that's for another time. 

I'm now thinking that those small automatic nozzles might be limiting the fueling needed to drive up boost with this pump.  Over in the MB IDI world, they're able to run huge Holset turbos by swapping in larger elements that vastly increase the amount of fuel available--larger nozzles don't really apply in that realm.  Since I was already planning to upgrade the nozzles, I guess I'll try that out. 
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: Zeitgeist on July 01, 2018, 04:32:16 pm
Just to follow up on this topic, I found that the cardboard snorkel tube running up the pillar was collapsed and causing lots of boost issues.  I also found that my wastegate was opening prematurely, though I haven't fully diagnosed that yet, so I've been driving around with the actuator unplugged--no wastegate at all.  I can get about 13psi peak and the EGTs have never gone above 850F.  I have some PP764 nozzles coming my way, so I expect I'll need to dial back the fueling in order to keep EGTs low.  The engine produces good torque for around town driving, but the HP isn't quite there out on the freeway.   
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: libbydiesel on July 02, 2018, 11:08:21 pm
Thanks for the update.  If the EGTs have never gotten above 850, then you can certainly increase the fuel a fair amount from where it currently is.  I look forward to hearing about the new nozzles.
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: Zeitgeist on October 13, 2018, 03:33:54 pm
Re-posted from the Samba:

My question: Can I remove the upper injection pump cover in situ, and are there any gotchas I should be concerned about prior to executing this task?  I guess it might be less problematic to just remove the head from the pump, but I don't want to assume anything.

Background: The engine in question is an ALH with a LR manual pump, though I assume this may apply to all VAG manual diesel pumps .

I went to start my van this morning and it started and stumbled (which it's never done since springing to life many moons ago), so I kept attempting to start. It would fire and die...until it wouldn't.

I checked for voltage at the solenoid with key on; yes.

I removed the electrical connector and then checked to see if the solenoid clicked when the connector was manually applied; yes.

I check to see if voltage stayed constant during engine cranking; yes.

I removed the incoming fuel banjo to see if there was fuel in the pump; yes.

I observed that when cranking after the previous test, the translucent fuel line refilled and the air bubbles disappeared; internal pump works.

Diagnosis: The fuel shutoff solenoid is bad.

The problem:
I cannot get a good purchase on the solenoid with the top cover in situ, hence the primary questions. 
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: libbydiesel on October 13, 2018, 09:32:24 pm
Yes, you can remove the pump cover with the pump in place.  Mark accelerator lever to shaft orientation.  Mark accelerator rest and full stop bolts if they're in the way .  It's then 4 m6 bolts holding the cover on. 
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: Zeitgeist on October 19, 2018, 06:14:38 pm
Thanks, I used that info to practice on an old NA pump, and then realized that none of my sockets or box end wrenches would fit in there anyway.  I eventually got the solenoid out (it was ugly), but the one I replaced it with did not solve the issue. 

I then  replaced the fuel filter and filled it with ATF.  Despite cranking many times, I can't get any of the ATF to appear in the translucent tube to the pump.  Can you confirm that the solenoid just cuts off fuel to the plunger, but the pump should still be drawing in and expelling fuel (through the tank return line) when the engine is cranked?  This is a real puzzler.   
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: Zeitgeist on October 19, 2018, 09:38:52 pm
I just installed the solenoid without the plunger, and it still won't fire.  I think this pump has completely failed internally. 
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: libbydiesel on October 19, 2018, 10:20:21 pm
The vane pump should move fuel through the pump when the engine is cranking even if the stop solenoid is not energized.  The stop solenoid only affects the high pressure portion of the pump. 

The 'fuel pressure regulator' sends fuel back to the pump inlet.  If that is stuck in the open position it could prevent the fuel from circulating.  I don't think that would prevent the high pressure side from operating, though.

Any chance the hub slipped on the shaft resulting in wrong timing?  That wouldn't prevent the fuel from circulating or spraying but would could cause it to sputter, die, and not restart like you initially described.   
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: Zeitgeist on October 20, 2018, 03:07:38 pm
I think you're on to something with the hub suggestion.  It appears that it's slipped from the position I set initially.  I'm still confused about the lack of fuel cycling through the pump, but I'll re-time the hub and deal with that issue when I'm back to baseline settings.  I've forgotten the lift measurement for these LR pumps; is it 1.40?

(https://www.thesamba.com/vw/gallery/pix/1835214.jpg)
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: libbydiesel on October 22, 2018, 08:37:42 pm
1.40mm is a good starting point.
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: Zeitgeist on October 23, 2018, 02:47:30 pm
I set it at 1.24 and it's still not even sputtering, nor is there fuel cycling through the pump.  I'm kinda stumped.  I suspect the pump needs to come off and be opened up for an inspection.  Is the fuel pressure regulator on the return line banjo?
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: libbydiesel on October 25, 2018, 01:29:19 am
The fuel pressure regulator screws into the top of the pump near the fuel inlet.  It is the little oval headed piece just on the other side of the pump center line.  I modified a 6 point socket to fit it.  IIRC the socket I used was 10mm.  A dremel chainsaw sharpening bit rounded out 4 of the flats to make the oval with the two center straight sides.
 
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: libbydiesel on October 25, 2018, 01:30:22 am
If that is not the issue then it would be internal to the pump, most likely an issue with the vane pump.  I had one vane pump seize on me once and it cause all kinds of havoc.
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: Zeitgeist on October 25, 2018, 11:09:34 pm
I pulled the regulator from the LR pump and my spare "learners" pump.  The plunger in the LR pump feels like it moves well and isn't sticking, while my spare regulator was stuck in the fully extended position until I depressed it.  Now the plunger in that one rests in roughly the same position as the LR.  Other than that, is there another way to test the regulator?  I assume they're set to particular pressures per each type of pump and aren't interchangeable. 
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: libbydiesel on November 04, 2018, 11:15:03 pm
Any progress or update with this?
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: Zeitgeist on November 05, 2018, 03:41:12 pm
I haven't really had much time to apply to this project, but this morning I tried a few of the last straws in my meager arsenal.  I swapped in a pressure regulator from a 4BT pump and the overflow banjo bolt regulator from another pump.  Additionally, I installed a small low pressure pump in the feed line just after the tank.  This is really just to help with priming the system during fuel filter swaps and the like.  It's triggered by a toggle switch in the engine compartment, and is only intended to run very briefly.  It allows flow through the pump when it's not turned on.   

Nevertheless, there's no love for me after all that.  It cranks and cranks, but doesn't even sputter in the least.  It's got to be an issue inside the pump.   
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: libbydiesel on November 05, 2018, 08:45:28 pm
Ugh, I'm very sorry to hear that. 
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: Zeitgeist on November 05, 2018, 10:59:50 pm
This vid shows the supply pump buried all the way up in the front, so it appears the whole thing needs to come apart.  Ugh, indeed.  Unfortunately I don't have any choice but to do this work myself.  I'll practice on my "learners pump".   

https://www.youtube.com/watch?v=_01gEg2ZMwg (https://www.youtube.com/watch?v=_01gEg2ZMwg)

I'm saving these here so I can find them later.

https://www.youtube.com/watch?v=RkDsEQx82do (https://www.youtube.com/watch?v=RkDsEQx82do)

https://www.youtube.com/watch?v=pLSefeFnF4w (https://www.youtube.com/watch?v=pLSefeFnF4w)

https://www.youtube.com/watch?v=n94BvDvDJgM (https://www.youtube.com/watch?v=n94BvDvDJgM)
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: libbydiesel on November 06, 2018, 06:17:07 pm
Yes, the vane pump is at the very end of the case.  It is not terribly complicated, though.  Mark any adjustments and keep all the wear items in their same locations (e.g. camplate rollers).  Taking pics as you progress through the disassembly would be wise.  Post up any questions.  It's not as hard as it might seem but still does take care and a clean work space. 
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: Zeitgeist on November 06, 2018, 07:47:21 pm
Thanks again for all your help.  Since I've never serviced an ALH (I assembled this, but servicing is different), is it possible to find TDC, and then slacken the T-belt tensioner and then remove the pump without having to disassemble the lower cover and crank dampener? 
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: libbydiesel on November 07, 2018, 07:32:04 pm
Yes, it is possible.  With the pump removed, the belt will have a tendency to jump this way or that around the crank sprocket.  Be extra sure that the cam and crank both are at TDC and pump pinned on reassembly.   
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: Zeitgeist on November 07, 2018, 09:52:06 pm
Thanks, I'll tear into it tomorrow and report back with what I have found. 
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: Zeitgeist on November 09, 2018, 01:04:41 pm
I pulled the pump yesterday.  Is there a DIY solution to the triangular bolts on the side of the pump?   
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: Zeitgeist on November 09, 2018, 05:51:23 pm
To answer my own question, I modified a Craftsman 1/2" six point socket with my Dremel so that the inside profile matched the triangular head of those bolts.  I'm currently trying to figure out how to remove the dark grey cylinder in the bottom of the pump body, so I can get at the supply pump.  So far I haven't found any obvious problems
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: Zeitgeist on November 09, 2018, 07:49:18 pm
I've got it completely taken apart, and the only issue I've found is some scoring on the pump housing, but this is not in the supply pump section.  Thoughts?

(https://www.thesamba.com/vw/gallery/pix/1842328.jpg)

(https://www.thesamba.com/vw/gallery/pix/1842327.jpg)
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: libbydiesel on November 09, 2018, 08:22:58 pm
That looks normal to me.  The vanes of the vane pump all move freely?  The key/keyway of the vane pump are in good condition?  Have you pulled out the high pressure piston?  Is that all fine?  Have you tried pulling a vacuum on the fuel supply line and confirmed that fuel flows without issue from the tank?
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: Zeitgeist on November 09, 2018, 10:09:35 pm
Everything I've observed with the exception of that wear on the housing appears to be operating well with no abnormal wear or stickiness.  I'm not sure what the high pressure piston is, but I have everything pulled off the pump, though I didn't remove anything from the upper cover.  I blew compressed air through my fuel filler neck and fuel flowed fine through the hoses and filter.   

I know this is getting a bit ahead of myself, since I'm still chasing a running condition problem, but how difficult would it be to swap over my 4BT pump head when I reassemble this thing?  I'm kinda surprised at how different the plunger housing is between the Cummins and LR. 
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: Zeitgeist on November 10, 2018, 05:57:55 pm
Here are the plunger housings from the 4BT, LR and a Prothe unit I bought probably a decade ago, when my ignorance was even more chock full of ignorance.

(https://www.thesamba.com/vw/gallery/pix/1842631.jpg)
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: libbydiesel on November 10, 2018, 11:18:55 pm
By 'high pressure piston' I was referring to the plunger. 

Have you confirmed that there is not any issue with the fuel supply to the pump (tank, filter, etc...)?

I probably wouldn't recommend swapping the fuel distributor/ plunger assembly at this time.  It would add another unknown to the equation. 

I would reassemble, pull fuel through the pump until full, and try running with supply and return submerged in a container of clean diesel.
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: Zeitgeist on November 10, 2018, 11:34:56 pm
You of course are absolutely correct, there's no point in introducing new variables into an unsolved running condition issue.  I'm just trying to find some kind of positive benefit from all this work.  So far I've not found any smoking guns inside the pump.   
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: libbydiesel on November 11, 2018, 10:08:54 pm
Chalk it up to good practice?  It takes way less time the second time.  :)

Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: Zeitgeist on November 11, 2018, 11:30:49 pm
Ok, so the thing that's bothering me about this, is the fact that even though the pump reservoir was full of fuel, apparently the plunger wasn't compressing anything through to the injectors.  AFAIK, the supply pump just draws fuel in to the reservoir and so long as the shutoff solenoid valve is lifted, fuel flows into the plunger chamber--I'm making up my own name for things.  Please correct any assumptions I've made here.

In my case, the supply pump appears to have stopped drawing fuel into the reservoir and the plunger stopped compressing fuel in the plunger chamber, so that's two failure modes.  This seems highly improbable.  When I installed that inline pump into the feed line, it theoretically should've at least addressed the failure of the supply pump, since it effectively filled up the pump reservoir.  The installation of the shutoff solenoid valve without a plunger and spring should've addressed the flow of fuel into the plunger chamber.  So far, I've found no obvious mechanical failures in my pump autopsy, so this all seems rather bizarre and doesn't add up. 
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: libbydiesel on November 12, 2018, 10:42:22 am
I see the puzzle.  That's why I recommended attempting to run it from a separate container of clean diesel.  That would eliminate the rest of the fuel system from the equation. 
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: libbydiesel on December 02, 2018, 01:20:09 pm
Any further progress on this?
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: ORCoaster on December 02, 2018, 03:14:08 pm
Libby, do you think the problem is with the little collar that allows the pump to spill any fuel going to the plunger?  Seems a likely spot to look if the internal vane pump is moving fuel through the body of the IP but nothing is getting to the delivery valves.

Only thing I can think of that would allow front side to work but not have back end spitting fuel.

Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: libbydiesel on December 03, 2018, 04:08:06 pm
Unless I'm reading the posts wrong, Zeitgeist says that neither the vane pump nor the high pressure pump are working. 
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: Zeitgeist on December 03, 2018, 04:59:21 pm
Correct, the pump wasn't drawing fuel into the reservoir nor was it compressing fuel into the injector lines.  Despite that, I've found nothing obvious wrong internally.  From what I can tell, the rebuilder did everything I would expect on a pump rebuild, so I don't think I can blame them. 

So far I've started reassembling the bottom section, but then other projects gained precedence over this one.  I hope to start back on reassembly tomorrow or the next.   
Title: Very little boost on my mTDI ALH Vanagon install
Post by: keycle on January 31, 2019, 11:06:34 pm
Planning on installing Frantz bypass oil filter on my 471, thinking Im gonna install T where oil pressure line goes to gauge and wondering where to out oil return from bypass filter.  Anyone have experience or advice with these?
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: Chuck1978 on March 23, 2019, 02:53:19 pm
Have you made any progress on this in the past six weeks?
Thank you for posting up those video links, that was very helpful, this is a learning experience for me as well, as I purchased an ALH/Rover mTDI that was never running right.
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: Zeitgeist on October 15, 2019, 06:27:25 pm
Ok, I should post some kind of follow up.  This project has stalled due to a lack of time, money or a combination of the two.  Toward the end of summer I pinned everything back up, and got it to fire up of a sort.  It will run so long as I keep working the throttle arm, but it won't idle or really increase RPMs very much.  It smokes and is not a pleasant beast in the least.  I guess I should mention that late last year I pulled the pump and tore it down, though I found no smoking guns or really anything obviously amiss. 

At this point I've added/subtracted so many variables to the diagnostics that it feels like I'm now chasing my tail.  So, I could have a combination of incorrect timing, and/or something not properly functioning in the pump's fuel governing area.  My concern about the former is that I'm still a little unclear about how to ensure a solid confirmation that the hub is properly positioned in relation to the shaft.  I used my dial indicator to set pump timing @ 1.45mm after installation on the engine.  As to the pump itself, I think I put it back together correctly (I mean, at least it fires up now), but there's still a lot of ambiguity about that since I don't have any kind of a manual for reference.

I wish I had a second pump to install and help eliminate some of those variables.  Anyhoo...that's where I'm at with the project.       
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: fatmobile on October 15, 2019, 07:59:21 pm
A pulse detector would help you see if the timing is right.
 Using a timing light.
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: ORCoaster on October 15, 2019, 08:46:12 pm
When I get the point that you are at with the too many variables thing I sit down and forget everything I did to that point.  Then I ask questions, what is it I really need to figure out first here?

You mentioned this:   My concern about the former is that I'm still a little unclear about how to ensure a solid confirmation that the hub is properly positioned in relation to the shaft.

I am assuming that you are talking about the IP hub and how it is lined up on the shaft.  And if the shaft is on the right cylinder.  If you look at the front end of the shaft with the hub off you have a place for the slotted keyway.  That keyway should be at roughly 10 O'clock position.  If you can tell where the hub slot is without taking it off, then hit the easy button.  If you need to rotate the position of the IP towards the 10 o'clock position then you are talking about a timing reset bit of work.

That is where I would start, verify you are aligned at TDC and the IP is indeed on #1 cylinder.  Once you are sure about that proceed with a normal procedure for doing the timing to 1.05 mm using your caliper stinger.  Not perfect but good enough to get it to idle.

Adjust fuel screw in the back to get it to hit a smooth idle spot and then adjust the stops or the levers on the IP. 

That is where I go when I have done so much I could stand in the drive and twill circles.  Neighbors love it when I do that. 
 
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: libbydiesel on October 15, 2019, 08:46:32 pm
I'm a big proponent of the pulse detector for timing but it will not differentiate between 1 and 4 or between 2 and 3. 

There is a keyway in the pump shaft, hidden by the hub.  That keyway should point toward the delivery valve for the #1 injector when the crank is at TDC and camshaft is also set for the #1 injector. 

Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: Zeitgeist on October 17, 2019, 12:44:25 am
I read the pulse sticky, but the last post was in 2015.  Are there any newer updates for sources or options I should be aware of when I research further?
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: libbydiesel on October 17, 2019, 01:24:46 am
It will run reasonably well with 1.45 plunger lift at TDC provided it is sending the fuel to the correct delivery valve (hub installed correctly and hasn't slipped).  While the pulse adapter is very good for fine timing, it won't help you see whether or not the hub is installed for the correct delivery valve. 

I don't think that diesel pulse adapters have changed much.  I got mine of Ebay years ago. 
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: Zeitgeist on October 17, 2019, 06:25:21 pm
Yeah, the hub check is first, but I like the pulse adapter for fine adjustments and basic confirmation that timing is in the ballpark once running.  And, I can use it on my MBs, though those are pretty easy to time with other fancy electronic gizmos.  According to Ebay, it appears the Gunson pulse adapter is all there is on their platform--~$180.

 
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: libbydiesel on October 17, 2019, 09:32:20 pm
You could get a tinytach transducer and ~$10 of parts and make your own.  I haven't done that but it seems quite doable.

(https://i.imgur.com/DDlD3GO.jpg)

(https://i.imgur.com/vG3qjnp.jpg)

(https://i.imgur.com/ptbdEeE.jpg)

(https://i.imgur.com/BhMPBRp.jpg)

(https://i.imgur.com/V1ZWhLa.jpg)

Of course that makes more sense if you want the tinytach.

Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: libbydiesel on December 05, 2019, 03:52:18 pm
Here's the board as best as I can tell:

(https://i.imgur.com/J99xdNb.jpg)
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: libbydiesel on December 12, 2019, 05:13:43 pm
Did you ever get the running situation sorted?
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: Zeitgeist on December 25, 2019, 07:41:55 pm
My new year's resolution is to find time to focus on the pump again.  I miss driving this van, and it's sad to see it just sitting there in my back yard.  Somewhere in my old PMs I have the procedure for setting the ALH hub on an LR pump, but I can't find it currently.  I'll also check the FAQ at the top of this page. 

I'm also in the process of re-doing the intake (Donaldson air cleaner) and exhaust in order to quiet things down back there. 
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: libbydiesel on December 26, 2019, 12:00:21 am
There's not much to setting the hub.  Rotate the shaft until the keyway is pointing the same direction as the #1 injector's delivery valve (before the bump on the camplate).  Insert your dial indicator.  Rotate the shaft until you get the plunger lift you want.  Lock the shaft using an appropriate bolt in the side of the pump.  Add the hub and pin.  Torque the nut (preferably with a holder for the hub so you don't stress the lock bolt/shaft).
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: Zeitgeist on December 26, 2019, 07:05:16 pm
Thanks, I'll dig in and report back in a few days. 
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: Zeitgeist on December 31, 2019, 06:51:10 pm
Ok, I have the pump on the bench and took a few pics to show the setup and final setting I arrived at once I pointed the key toward #1 delivery valve.

Hopefully this shows the key and #1 valve.
(https://www.thesamba.com/vw/gallery/pix/1985018.jpg)

Here's the gauge dialed to zero (the pic is a bit parallax, but the small pointer is at the line).
(https://www.thesamba.com/vw/gallery/pix/1985017.jpg)

This is my final setting, 1.41
(https://www.thesamba.com/vw/gallery/pix/1985016.jpg)

I'm hoping someone can confirm my settings before I torque down the hub.
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: libbydiesel on December 31, 2019, 10:31:24 pm
That all looks correct to me. 
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: Zeitgeist on January 03, 2020, 03:05:05 pm
Thanks, your sign-off provided me with the assurance I needed to install the hub.  I ended up setting the timing to 1.45, but I could not for the life of me find a definitive torque spec for the hub center nut.  I found folks stating the specs were from 33 to 70 ft/lbs.  I ended up opting for 40 ft/lbs.  I hope to install it on the engine later today or tomorrow. 
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: libbydiesel on January 03, 2020, 08:19:19 pm
I usually do 60 ft-lbs while holding the sprocket/hub.  The early sprocket with key had a 33 ft-lbs spec.  I feel like the hub with just taper and no key should have more, but that's just conjecture. 
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: Zeitgeist on May 04, 2020, 02:26:49 pm
Ok, I'm back on this project due to an unfortunate mishap with my daily driver, which cracked its cylinder head.  The added twist to this project is that I need to swap in another turbo because the K14 needs to go back on my OM606, as its getting swapped into my daily.  I need some advice as to what turbo and manifold I should buy to get the ALH back up and running.  The K14 was always a lousy match so I'm happy to get rid of it, but I don't know of a good and not too expensive option for an mTDI.  One not very good option would be to remove the T25 from my daily, but that's probably too big.  A VNT seems like the best option, but I'd need to figure out how to control the vanes, and I would have to revamp my driver side engine mount since the stock ALH manifold will run right into it.  Prothe (yes I know) claims to sell a stand alone turbo controller using the stock MAP and N75 valve for the VNTs https://www.hansautoparts.com/ROT906021A-Turbo-Controller.aspx .  Does anyone have experience with this?

Oh, and I still need to get the engine running, but that's just putting stuff together so I'll post about that later. 
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: libbydiesel on May 04, 2020, 10:25:09 pm
A K14 from an AAZ (different from the K14 you used) is a decent wastegated turbo.  The Garrett 1749VA from a B5.5 Passat is a good match if going with a VNT.  If you get the manifold as well, there is a good chance it will mount up without interference although that depends on your driver's side mounting bracket.  I have heard from one individual who ran the Prothe VNT control and the feedback was not positive.  I don't recall the details on it but it is not a route I would take. 
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: Zeitgeist on May 06, 2020, 02:10:40 pm
Without a way to control the vanes and the interference issues, I'm reluctant to invest in VNT...yet.  Right now I need to get this thing running again in the quickest manner, so I think I'll just go ahead and use that T25, since its a known entity.  It's coming off of a 2.5L instead of the 3.0L source for the K14, so maybe it'll spool better.  It would start spooling just off of 1k rpms on the 602 engine.  Anyway, I already ordered a T3 to T25 adapter and some V-band clamps so I can start welding up a new exhaust.  I'm going to move the cat closer to the downpipe so it heats up faster.  It's also getting a larger muffler and a new Donaldson air cleaner, so hopefully it will be quieter. 

Oh and, I recently read that some folks have had good luck running a GT2052 wastegated turbo on TDIs.  These use a T25 flange, so maybe I can upgrade to one in the future.  Any experience out there?
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: libbydiesel on May 06, 2020, 03:36:01 pm
I have not used the GT2052 turbo.  I believe Karl M. has recommended that before.

Some folks have run the Holset 221 or 200.  I have not run those either, so I cannot comment.  Maybe send a note to Gizmoman as I know he is running one on an AAZ.   
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: libbydiesel on May 06, 2020, 07:40:57 pm
I would also mention that the VNT 1749VA from the B5.5 passat is relatively available used right now, would be a better match than the stock ALH VNT 15, and it imight fit with your driver's side mount if you use the matching b5.5 exhaust manifold. 
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: libbydiesel on May 06, 2020, 07:44:09 pm
Here's an example:

https://www.ebay.com/itm/VW-Passat-2000-2004-B5-5-AVF-Turbo-Turbocharger-With-Manifold-038-145-703-G/332663018104?hash=item4d7442d278:g:tJcAAOSwG-1WwzK1

I would also mention that on my '79 rabbit I mounted an external wastegate to the EGR valve port and have just run the vanes stationary but with the ability to adjust their angle.  That basically makes it a wastegated turbo that you can size to fit your preference.   
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: Zeitgeist on May 06, 2020, 09:57:12 pm
Very interesting.  Unfortunately that B5.5 design would interfere with my intake manifold, unless I welded up an extension for the turbo to hang off of.  Or, can that actuator be re-clocked?
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: libbydiesel on May 07, 2020, 12:43:48 am
The actuator cannot be re-clocked without a lot of custom work.   
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: Chuck1978 on September 28, 2020, 01:40:55 pm
How is your project running with the new mTDI pump?

I also have PP764 injectors and a GT2052 turbo, although I'm contemplating putting an AAZ K14 turbo on the ALH mTDI to save the GT2052 for a 2.0 BHW/ALH hybrid
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: Zeitgeist on September 29, 2020, 07:11:28 pm
Sorry, I didn't see this until now.  It's running excellent.  The power and smoothness is exactly what I was looking for when I started this project.  It's a complete joy to drive, except the gearing is still too short with the DK trans and 28.5" rear tires.  I just received a 3.08 R&P and the auto trans assembly should arrive tomorrow.  I'm hoping this combo isn't too tall, as I've not seen nor heard of anyone running this tall of a trans with a TDI.  The vendor tried to convince me to get a 3.27, but I wanted to take one for the team and advance our collective understanding.  Please cry for me if this is a flop. 
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: Zeitgeist on June 09, 2021, 02:48:37 pm
The van has been humming along just fine, with excellent power.  Unfortunately yesterday I totally grenaded the transmission.  The R&P is clearly missing large chunks, which was painful to hear while I limped five miles back home.  I'm sure it's a total loss. 

Thankfully, I have a backup auto trans with a 3.08 R&P, but I still have to reassemble it and order a new adapter plate and starter adapter.  No rest for the wicked. 
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: Zeitgeist on June 09, 2021, 02:51:27 pm
Forgot to mention that I recently bought an '04 Passat Variant with a BHW TDI, but of course it's in nearly constant limp mode while I await my new VCDS dongle/cable.  Sure wish I could mTDI this thing...
Title: Re: Very little boost on my mTDI ALH Vanagon install
Post by: libbydiesel on June 09, 2021, 06:34:20 pm


WOW!  I'm sorry to hear about the trans death!  Eager to hear about the auto swap, though!  "The trans is dead.  Long live the trans."

Hopefully the limp mode issue on the Passat is easy to sort out.