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Engine Specific Info and Questions => mTDI Mechanical TDI Conversions => Topic started by: rodpaslow on April 06, 2015, 11:35:55 am
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I've just had time to swap in a cheap SDI intake and larger injectors (hflox .25 for original 1Z). This car has a 2052 turbo in it - it was pretty fast at pump maxed out the the original injectors.
The one thing I'm not 100% sure about re-stetting the pump for these injectors (not worried about smoke amount) is how much to turn the fuel up to? Basically turn it up so when the turbo is doing it's thing it's mostly cleared up the smoke out of the exhaust?
Any tips anyone might have?
Thanks
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I seem to have a problem now since the swap - I'd like to confirm what the problem might be.
I have a low idle - about 750 rpm, I can fix that as I think the idle spring just needs an adjustment / change as I have other from AAZ I might try a different spring if adjusting spring doesn't help.
Main problem is anything above 2800 rpms it's starts to do something, almost seems like it's missing or shuddering, not sure what the right term is but it seems like its starting to miss. I had backed the fulling off full - about 2 turns and it was doing something like that even a bit at idle, so I turned the fueling up about 1/2 turn from full and idle seems good, but hasn't helped above 2800. (seems louder knock than with old injectors, but much, much smoother running).
I get very little boost - only about 10 psi when I try to get on it-some smoke, but not like it should be, and shuddering starts.
I have the pump advanced at max - it's got land rover internals in a AAZ housing, land rover cover with boost unit - I checked and it's set at about 1.400.
Would retarding the pump from this help - new injectors would/should have proper breaking pressure (1Z/AHU) from the old injectors (had them done by Giles)?
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Are you sure you're not getting fuel starvation?
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It shouldn't be, i have the original pump (was a gasser) in the tank and a regulator in the engine bay to bring fuel pressure down to a useable pressure. It supplies a steady stream to the injector pump. I did some changes to the placement of it when I replaced the intake manifold. I guess that will be something to check and make sure I'm getting sufficient supply yet.
My other car has the same setup with a 1.6TD, last fall I had fuel supply problems with it, but it would start loosing power I slow down it would idle and then die. And would be very hard to start. The fuel pump had given up the ghost and had to change that on that car. This Mtdi doesn't act like that. Starts immediately. But I will check fuel supply anyway.
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Bingo. Lots of folks have had issues with the stock feed pump restricting fuel flow. It's a high pressure pump but it doesn't provide enough volume to supply a VE pump I'd bet. At high revs there is a LOT of fuel passing through the injection pump and back down the bypass. While it is nice to have you shouldn't actually need a lift pump.
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Perhaps removing it from its place in line as a test might be in order? Volume is key here not pressure.
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You could temporarily run from a can to see if it is a supply issue.
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It only seems to do it badly when cold now. I hate to have to remove the pump as it's nice to have when priming it. With larger injectors, these are .25, how much volume is needed - just wondering if the stock fuel line is sufficient?
Car seems much louder now, I backed off the timing a bit and seems to have helped slightly - have you, other members that have gone to bigger injectors noticed the same?
(not so much louder inside driving, with spring I drive sometimes with the window down a bit, just seems really loud).
I also have boost issues that may be related to fuel, above. Max pressure seem to be 13-14 psi. It's a brand new gt2050 wastegate turbo, may have remove boost line from wastegate and see if that changes anything. Pump fuel screw is maxed out. I don't see a lot of excess smoke.
How can I test to see if the pressure pump isn't supplying enough - it only happens at about 3/4 pedal above 2500 rpm or so? Dis-connect it from the tank?
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Larger injectors shorten the injection event for a similar amount of fuel. The shorter injection event results in more noise/clack.
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I think this weekend i will pull the top off and fix idle speed, that will help idle klack/noise.
Would a permanent extra holder like a can of somekind makeup for shortfalls with the pump volume. When it was short it would pull from the can otherwise be happy with the pressure and volume from the pump. I hate the idea of screwing with the fuel tank as I did that with my 1.6TD and ended up going back to the pump that was already there.
How much extra volume would be necessary. The only times I floor it would be accelerating on to speed and where I live, lets just say its flat.
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I checked the volume of fuel from the pump, flow is fine. I used a yellow diesel can, best I could tied to the front of the car (put a hole in the cap to feed pump of a diesel can) and I couldn't detect a noticeable difference.
I took off the top of the pump a couple times as I wanted to increase idle from the ~750 rpms it was at (by my in car tach - double checked with an electronic tach). I had it at about 1100 rpm the first time - the rpms would vary because I think the intermediate spring was fighting against the idle springs. Second time is about 950 - which is still a bit high.
Could the shortage of fuel/boost be the aneroid?
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(http://s28.postimg.org/6z71y99vt/Bosch_VE_LDA_Diagram.jpg) (http://postimg.org/image/6z71y99vt/)
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Lever that centers on M1
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Is there a way to test it - pull the grooved pin and (engine off) and move to full throttle should test if the pin is stuck, of if it comes out should tell me if it's working okay?
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Is there a way to test it - pull the grooved pin and (engine off) and move to full throttle should test if the pin is stuck, of if it comes out should tell me if it's working okay?
That's exactly what I do. Pull the LDA pin out and move the throttle lever to full fuel and measure how far the pin inside the LDA pushes out. I use the shank side of drill bits to see how far the pin has moved out into the bore. Then I pull the top off the pump and manually move the lever that pivots on M1 and measure again with drill bits to see how far the pin is pushed into the bore. If the pin can move into the bore farther manually than that's not the problem.
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It does sound like you have a fuel starvation issue. A good way to test your setup is to T in a vacuum gauge at the fuel inlet of the pump. Under full load you shouldn't see more than 5" of vacuum. Running a primary fuel pump you should never see any vacuum at the injection pump inlet but like Vanbcguy mentioned, most pumps don't provide enough volume for these injection pumps.
If you have enough fuel pressure at your injection pump inlet under load then it's time to check the internal pump pressure under load. this is not as easy. I made my own pressure tap by drilling through the fuel out bolt to install a pressure gauge. If you get this far I can mail you mine so you don't have to ruin another one. Lots of adjustments can be made for optimizing the internal pressure which directly controls dynamic timing.
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I just rebuilt the outbolt I have customized to be able to slide a second inlet collar under it. I was rebuilding a pump and snapped the solder joint
I run 45 lbs of pressure at idle and it ramps to 108 under high revs
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I didn't get a chance yesterday to check the lda, I'm now having problems with the shut-off solenoid. I've got a few I tried yesterday and they all operate about the same. If the car has been sitting for an hour or so it works just fine. But if I shut the car off and want to re-start it immediately, it will not start unless I disconnect the valve's electric connection and then re-connect it or fiddle with it until it works. The other car's I've worked on this should 'click' when power is applied - correct? Maybe I need a new one.
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It is probably the wire not the solenoid.
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Have you pulled the stop solenoid? That is a common place for swarf to build up when the pump is self-machining.
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I change the wire thinking it was the wire, but that didn't help, I have to check the lda after work today, so I can pull that at the same time an make sure the inside of it is clean. I made sure the pin was, but didn't think about the inside, where the pin goes in.
I think, by the sound of what you're telling me, is to get rid of the in-tank pump and regulator in the engine bay and get back to proper setup where the pump pulls it's own fuel.
I just hate to do that, as I have the exact same setup on same, my other car, MK3 only it's a 1.6 td. It's easy enough to do though...
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Solenoids wear some and may have a scraped side to it. 600 grit paper might take it out. But gunk from the pump does seem to collect at that part.
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I cleaned the inside part of the solenoid as best I could, got it so the center of it was shiny metal, some dirt/maybe oil did come out. Works like it should now.
Next - I pull the top of the lda and pulled the pin & diaphram out to check to see if the pin extends when or near max throttle or at max throttle. I watched a video (don't remember if it was a 200 or 300 LR pump) and at a certain throttle point the pin is supposed to come out/extend. My pump doesn't so there is definitely something not right. The pin connects to a pivot that extends another little pin on the underside of the top-and moves a bracket of sorts with a bit of a finger. This finger should move the control lever - is that correct? also if the lda pin & diaphram are out it should extend the pin, correct?
where is it supposed to catch/push the control lever?
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Pictures I've looked at, it looks like the very front plate of control lever (towards front of pump) will push against the finger, moving the lower pin in - pivoting the arm - moving the upper pin against the lda pin. this is in reverse to when the pump is working properly.
(http://s28.postimg.org/8iki18cgp/ve_180.jpg) (http://postimg.org/image/8iki18cgp/)
Is it possible to have the throttle linkage too far back so the idle spring in on the wrong position of the control lever (more towards back away from drive end) not as shown above?
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i bet on fuel starvation if LDA is a performance one... if it isnt... than its because you need a good LDA ... looks like the easy way to find them in america is looking for cummins fuel pin... maybe there is something cheap on ebay... or yo may make one by yourself... because looks like they aren't cheap... just take a look on google you will have an idea of how it should be more or less... worst case cenario alot of roll call...
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LDA is just a smoke limiter, you can make the same peak fueling even with a crappy LDA pin, you just won't be able to keep the smoke down before the turbo spools.
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I actually have a couple pins, the stock LR pin (not bad if it`s turned to steeper side) and one actually 410 gave me when I bought a car from him, it seems to work good as well. I had it in last and it looks like the pin touched the lda pin after pulling the lid off the pump tonight. It only went maybe .125 up the pin. I get 10 to 11 psi at max throttle so it makes sense that the lda pin moves a bit.
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I`ve got time this weekend and I`m going to remove the pressure fuel pump in the tank, remove the regulator and have the injector pump pull from the tank itself. The lda still seems way to stiff to start moving, so I pushed on the little pin down the hole and it seems to have helped free it a bit. I`m going to do the governor mod and see it that makes any difference as well. If It`s still not working - pump pressure may be the next thing to check.
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I have the top off the pump. I wanted to make sure where the control lever hits the boost pin finger.
(http://s25.postimg.org/rl2l15rin/20150416_203156.jpg) (http://postimg.org/image/demu5xgnf/full/)
image posting (http://postimage.org/)
If the pump is turned up to max fuel, does that affect the lda at all? just wondering if it's at max, if the lda cannot function? It seems that once the throttle is full forward the lda won't do much, except keep the throttle from being able to go to full fuel.
I still think my mechanism that functions with the lda boost pin was sticking, and sticking so it was hard to move. Once past sticking part it was easy to move. I have it moving easily now. With this fixed and governor mod & changed fuel system, hopefully my problems will be fixed.
This control lever is quite a bit different from the Vw's It has an additional pivot at the top, and spring farther below. Works the same. I'm amazed that the contol collar from idle to full only moved about 1/8" or so.
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It seems that once the throttle is full forward the lda won't do much, except keep the throttle from being able to go to full fuel.
That is exactly what the LDA does. It prevents the control collar to reach the max fuel position until boost pressure and boost pin rise allowing additional motion based on boost pressure. I don't know that I would say that 'it doesn't do much'. I think that preventing off-boost smoke is really beneficial both to my wallet and to the canaries.
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I agree.
So I should see the pin push out at max throttle - if not it's still sticking too much...
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I had a problem shiming the governor, I lost a c-clip. I was able to test to see if the pin on the LDA works, and it does now with little effort by the throttle lever. Only I noticed if the lever isn't set properly - high enough it won't come out. I've been up to now setting the actual lever that connects to the throttle cable, more or less by fueling; meaning I'd set the fueling an couple turns down from full and install the throttle lever where it idles properly. I need to review this and see if that's the correct way to do it as I didn't mark it when I first took it off the pump.
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I didn't change anything with the fuel system. I followed a few posts on here about the throttle lever and started it, once the top was back on, about half way so that near full throttle the lever would force the little pin out into the lda pin area (left the lda top off till the end). Put everything back together. screwed the fuel pin in about where I figured and then set the idle...and majic...the car pulls hard now and will shoot past 20 psi easily - just a bit too much smoke now. That's easy to adjust down and adjust the lda to where it's just starting to get gray. I love it, the Mtdi is so much easier. A bit of patience setting everything, now it's a fast car. Much faster than my 1.6td.
(http://s25.postimg.org/hai92bp1n/20150421_201952.jpg) (http://postimg.org/image/hai92bp1n/)
Fantastic. Thanks for all the help!
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Nice work Rod. MTDI's are definitely more of a challenge to get right but once you get there, hold on!
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I have one more question-it's pretty darn fast now. I know vanbcguy is running a different, modded cam. I'm wondering if it would make a difference to help mid-range even more (2500-3500 rpm). I don't go over 3500 rpm often. Just curious if it's worth it? Thanks again for the help!
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The "Stage 2" cam would be a pretty good match for your turbo/injectors.
Here's a few dyno graphs I found on that "other" site:
http://forums.tdiclub.com/showpost.php?p=2915670&postcount=1
Small HP gain in terms of peak numbers, but significant gains in the 2K+ RPM range till it hits peak, and more area under the torque curve...
This one is a "Passenger Performance" cam, Passenger doesn't do VW diesel stuff anymore but a little birdie told me that this is really a Colt Stage 2 cam more or less. Makes sense as both Colt and Passenger are close by each other out in the valley here.
http://forums.tdiclub.com/showthread.php?t=162024
Again small visible gains but higher peaks.
Universally though you see lower EGTs, which in turn means you can crank the fuel up a bit more, which itself will gain more HP. So yeah, you'll definitely see some gains.
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At the moment if I floor it to see my highest egt, I can get up to about 1300°F at roughly 20-23lbs boost. It's hard to watch everything because before you know it your doing 80 mph.
Where'd do purchase yours? Kerma in US? Do you need to send your old to have it re-done?
I think I will look into getting one sometime soon. If it's going to help EGT ans smoke some, it only makes sense.
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Colt Cams is actually local to me here in BC, so I just drove out and bought my cam directly from Geoff. Nice guy, we chatted a bunch.
Kerma has an exclusive distribution contract in the US and I think the UK. I bought a brand new cam, not a regrind (not sure which product Kerma is selling) so there was no core to return.
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My buddy picked up a couple directly from Geoff as well. He got the stage 3 and I got the stage 2. I had to do a little bit of grinding of the lifter bores [some heads don't need any grinding] to clear the stage 3 but the stage 2 is a straight drop in. At the time Geoff was working on a stage 4 cam for the ALH. Roughly the same as the stage 3 but with more duration and lift on the exhaust.
I would recommend a Colt cam to anyone but only after doing other mods like bigger nozzles, larger turbo, larger exhaust and cranking up the fueling. A three angle valve job and porting go very nicely with an upgraded cam.