1.6 pump on a 1.9 VW Westy with a Holset

[Gizmoman]

1982 Westy with 1.9, Holset turbo. Early morning last Tuesday my wife and I took off on a 1700 mile round trip from San Diego to Eureka, California to visit my daughter and two grandsons. We slipped into the millions of others heading out for the holidays and by the time I had made it to LA, I began to have some serious issues.

Typically I can boost to 10-12 psi if I floor it which will get me up most grades at 60 mph. In the stop and go holiday traffic going through LA on the 5 North, I didn't realize just how bad things were getting. By the time I reached the long 6% grade leaving San Fernando and heading up towards the Summit, my boost was only going to 7-8 psi which kept my top speed at 50. Once I hit 7 psi, any more pedal just made it stumble and rapidly loose speed. Needless to say, I made it all the way to Eureka with this issue - going into severe headwinds to boot!
I stopped several times, cranked the fuel screw in, look apart the LDA - even removed the star-wheel to lessen the load on the diaphragm spring - no improvement whatsoever.

Once we arrived at my daughters place and after having many many stressful hours to think about it, I decided that the 12 volt pump I had installed several years ago had something caught inside it and was blocking my fuel delivery. I know an electric pump is not needed as the IP can pull plenty of fuel without it. I just installed it for the odd time I may run out of fuel (never have), it would be nice to help get the air out.

Anyhoo, I replaced the pump and the entire line from the new fuel tank I recently installed. I did find a few tiny bits of rubber or sealant in the pump and sure enough, it now boosts to 10-11 psi and climbs most any hill at 60, even 65 if there's no headwind.

My apologies for the long winded post but I am looking for advise on what it will take to get this thing to fuel more than it does. My long trip and subsequent fix proved clearly how boost and fuel are directly proportional. I have turned the fuel screw all I care to as the idle screw is backed out to it's max. Any more fuel and it will simply raise the RPMs and I'd like to keep my idle at 850.

For a bit of history, the pump is from a 1.6 (was like that when I bought it). I had the pump tweaked by a pump guru in Canada named Giles (highly recommended by the folks on this forum) and at that time I had told Giles I was running a KK-14 turbo which generally maxes out at 12 psi. However, the Holset turbo I finally ended up installing can do 20 all day and I built the engine to take it. My thoughts are that Giles tuned the pump for the 14 and no matter what I do, it simply can't deliver the required fuel to boost past 10. I recall that when Giles informed me that I had a 1.6 pump, I asked him why the PO may have done that. His response was that the 1.6 was a bit smaller but not to worry as he could make the pump fuel plenty - again, he was tuning for the KK 14.

Also, as I mentioned earlier, I recently installed a new fuel tank - stock tank probably for gasoline. As I was swapping out the old hose/fuel pump affair, I noticed that the fuel came out of the fitting on the nearly full tank quite slowly. It's not a dribble but it is certainly less than I was expecting. I did straighten out a coat hanger and jam it quite a ways in to the tank output tube just to make sure it was clear. The hanger wire did stop against something quite a ways into the tank but I have no idea if it was a screen or just a sharp bend in the output tube. Regardless, it didn't change the flow at all. I still wonder of there is a very fine mesh screen in there that would allow gas to flow easily but is somewhat restrictive when diesel fuel tries to get through.
I should mention that I have posted this on the SAMBA as well and those folks will possibly know more about the fuel tank than most of the folks here.

If anyone has any thoughts on a possible tank screen and how to clear it, or if the 1.6 pump is too small, or a way I can get this pump to move more fuel, I'd really appreciate it.
The van runs great now but If I could get at least 15-16 lbs of boost, It would be wonderful!

Thanks for reading my novel and please share any ideas you have as to what the problem may be. I have checked for boost leaks and only found a few tiny ones which I have fixed. Stopping these really didn't change anything either.

Jim

[libbydiesel]

If you have run out of idle adjustment but can still turn the max fuel screw in further, it is possible to jump the accelerator lever to shaft orientation one spline so the shaft moves toward idle (CCW), then turn the max fuel screw in further to gain some added fuel. 

[Gizmoman]

If you have run out of idle adjustment but can still turn the max fuel screw in further, it is possible to jump the accelerator lever to shaft orientation one spline so the shaft moves toward idle (CCW), then turn the max fuel screw in further to gain some added fuel. 

Hmm, that's an interesting thought and may certainly be worth a try. I need to get my wife to follow me when it gets warmed up (the engine) and tell me if she sees any smoke when I tromp on it. As far as I know, it doesn't smoke at all or very little but to be honest, it's very hard to tell. A bit of smoke would be worth it if I could boost to 18 psi.

I may look into the possibility of something lodged inside the pump itself that may hinder volume as well. The fuel has always been filtered well but there's no telling if I allowed something in during a hose change or whatever. I do recall the turbo hitting 18 psi but it was very brief and has only happened a few times (a long time ago)

[libbydiesel]

I would try adjusting the lever to shaft orientation before opening up the pump.

[ORCoaster]

Thanks for the reminder Libby, I used this today and now have a better responsive pedal and hill climbing power. 

[Dubdoc]

Giles does set the pump up for a single specific application. If the turbo has changed, the pump should go back to Giles for a "reset". My AAZ (Giles pump) boosts to 24 psi regularly and no issues at all, but I told Giles the setup I had and he tuned it for that setup.

[Gizmoman]

I have the utmost respect for Giles and he did do exactly what I had requested - build the pump for the K14.
The cost to send it back to him is way outside my budget and if turning the fuel screw in and re-positioning the throttle arm works, that's the best I can hope for.
The K-14 was just not enough turbo for what I wanted so I installed the Holset. Hopefully, now I just need to add more fuel.

I am hoping that doing that, plus working with the LDA adjustments (pin grind, spring rate and star-wheel) I can get the boost up without too much smoke - ideally zero.

So far, every time I do what Libby recommends, I come our a winner. Every time I don't, I just make a mess of things

[libbydiesel]

Don't grind the LDA pin.  That method just reduces the adjustability of the pump.  It's almost like grinding the floor of the car under the pedal instead of adjusting the max fuel screw.

[Gizmoman]

Don't grind the LDA pin.  That method just reduces the adjustability of the pump.  It's almost like grinding the floor of the car under the pedal instead of adjusting the max fuel screw.

Thanks Libby,
I wasn't planning on grinding the pin - It's already been ground (I believe either Giles did it or the PO). I was referring to the pin that has been ground - sorry for the confusion.
I am now into it and am sorry to report that I have removed the throttle lever entirely including the top spring. Had I been smarter, I would have taken photos and noted what the two opposing spring hooks hook to and what's related to what. Now I'm not sure and realize what a PITA this is going to be to get back together.

If anyone has any tips or a diagram, I'd really appreciate it.
I did turn the fuel screw in about 1-1/2 turns and I get a big puff of black smoke when I rev it. The engine was cold though so it really isn't a true indication. Bringing the throttle on slowly shows no signs of smoke.
I also started it with the throttle lever off and it idles at about 650 so it's good to know I can get to where I want to be idle-wise.

Again, any tips on the top spring installation would be very helpful.

[libbydiesel]

Post a pic of the top of your pump, springs, etc...  There are different versions.

[Gizmoman]

I finally got the springs sorted and re-indexed the throttle arm. Then I took it for a spin hoping for some major changes. - 9 psi max what the heck is going on?

I pulled off the freeway, turned the screw in another turn - idle is back up to 950 - but I gotta know why it's not fueling - again, 9 psi max.

Ok, the stinking boost gauge must be wacky. I backed it down to the shop, turned on the compressor and fed air into the boost line where it T's off at the LDA - 9 psi max  .   When I first turn the key on the digital gauge does a fancy run up to 40 psi and back to zero and one would think that shows its working within that range. Apparently not, because all it goes to with the compressor (regulated to 30 psi) is 9 psi.

All I can say is what a bad experience I have had with Glow Shift gauges. My oil pressure gauge is acting weird as well so I'm going to yank them both out and get some quality gauges. Till then I have no idea what kind of boost I am running. As soon as I do, I will report back.

Thanks for all the help and my apologies for the big waste of everyone's time trying to solve a problem that didn't exist.

Jim

[libbydiesel]

I know the feeling.  I've done a remarkable amount of work on a couple vehicles because of gauge issues.  I'm eager to hear what the results are with another gauge.

[ORCoaster]

OH YEAH, chase some crazy temps because of bad senor on the electric style gauge.  I even went so far as to send it back to Auto Meter and they at least were good to send me the same gauge back but with a different sensor.  So now I know when it says 210 F it really is and not somewhere around 185 F.

When the gauge came back I did the boiling water test on it and that convinced me that all was well with the reading. 

But I have a volt gauge on the Caddy that I don't trust now.  Might just be connections on that one.  You know the rule.  Check the grounds first. 

[Gizmoman]

I'm going mechanical from this point forward. Hate to have to run an oil line to my dash but watching my oil gauge hit zero while I'm doing 70 on the freeway really makes your butt pucker. Pull off frantically only to find oil level is fine and now the gauge reads 35 at idle. And this bad boost gauge has been providing bad readings from possibly the first few weeks after I put the Holset on - all that time chasing a ghost. Sadly I was hoping that if it ran this good at 9-10 I was imagining what 18-20 would be like. It could be there already or even higher for all I know.

If anyone wants to chime in with what they think is a quality gauge manufacturer, I'd be interested in your opinions.
As soon as I get a new boost and oil pressure gauge and get them installed, I'll make sure to let everyone know what I am truly running.

[libbydiesel]

I've always done mechanical boost gauges and have not had issues.  I'd recommend boost/vac despite the fact that diesels don't typically produce vacuum.  If there is an intake restriction (e.g. clogged air filter or intake tube collapsing), there will be vacuum prior to the turbo spooling and knowing that at a glance from a gauge is helpful. 

I have had nothing but problems with electronic oil pressure gauges.  I know well the puckering feeling when going up a steep hill a couple hundred miles from home while the oil pressure reading plummets...  only to find out the sender is crapping out.  I always keep the idiot light working (and the oil pressure warning system if equipped) just as a sanity check.  I had a mechanical oil pressure gauge on one of my vans.  It worked, but in cold weather it would take a long time to react.  Maybe not a problem where you are.