WOT at start up... with my foot off the pedal

[br29029]

So I've been lurking for a while, but I finally decided to make an account because I have a question I can't find an answer for.

I bought a non running 1986 jetta a little while back. It would crank fine, but it just wasn't getting any fuel, so I replaced the fuel lines and filter hoping that it was just an air leak, but no luck. I eventually figured out that it was the rear seal of the IP. I bought the resealing kit and replaced the seal by leaving two bolts on at any given time, backing the head out just far enough and removing and replacing the seal.

And that fixed it! sorta...

When it fires off (after 3 or 4 seconds of cranking) it goes like I have my foot mashed on the gas. Any one have any idea why this is? Could I have messed up some pump internals replacing the seal? I think the car has been sitting for months (years?) could something inside the pump (governor?) be gummed up? I'm really stumped, and I really hope I don't have to open up the pump.

[Ira B]

Welcome.


First I would want to know why it was sitting for awhile.

If it had veggie, crappy bio or who knows what else run through it there could be gum and/residue in the IP.
Before trying to start it again and risk damage due to over rev I would pull the top cover off the IP, (which can be done in car) and have a looksee in there. My guess is that you will find it pretty icky.

[br29029]

Thanks!

It was not running because he was getting air into the lines, or so he says. I know he was running some biodiesel, (he insisted it was always commercially made stuff), but the thought had crossed my mind. I guess I will open it up and have a look.

If it is all gummy any ideas to clean it out without taking the thing apart?

[82vdub]

When you resealed the IP, how far into it did you get? Did you do anything internal except replace external seals? Did you remove the throttle arm? The throttle arm could be on wrong and you're calling it to be WOT. Did the car shut off with the key, or did you have to shut it off some other way?

[br29029]

I just slightly backed off the cast iron head and replaced that o ring. I didn't touch any adjustment. And WOT probably wasnt the best term, the throttle position is at idle, but the pump is delivering way too much fuel. The max fuel screw is still at the original position.

Could I have messed up anything internally to do make this happen? I realize now I should have put a bolt in the timing hole...

and i did shut it down with the key

[hjalbert]

if nothing has been changed inside the pump, and it was not doing that before (granted you are relying on the word of the previous owner) then it is probably just stuck and gummed up. When you remove the pump cover, make sure you mark the location of the accelerator arm assembly thingy and pay attention to how the springs go. also, when you say that the max fuel screw is in it original position, are you talking about the screw on the cover that stops the accelerator assembly from advancing any more (opposite the idle adjustment) or are you talking about the screw above the cast head on the block side of the pump that takes a flat tip screw driver and iirc a 13mm wrench to adjust?

[82vdub]

Something happens inside the high pressure end if you don't put a bolt in the timing hole to keep something pushed tight against the IP body. Search through the posts on here and read. I believe it was libbybapa that posted the original idea on how to do it and what happens if you don't use a bolt. It could be a gummed up internals too.

[br29029]

so I took the top off of the IP and there were a few surprises:

there was crud from old fuel, but nothing too bad, and not enough to cause problems, I don't think.

The two springs that sit in the IP head and push against the control lever (the bit with the nubbin that moves the sleave that controls the size of the size of the injection) were intact. Oddly, the two springs that are part of that lever were missing, I could take pictures if anyone is curious about what I am talking about.

I am going to try fishing the springs out with a magnet because I don't think you can take the head off without removing the lever, and I don't have the special three point socket for that.

[Ira B]

Sounds like corrosion may be the issue.
Everything has to be super, super clean and move freely or you will have problems.
FYI, you can make that three sided socket pretty easy by grinding out the half the lugs in a 13 mm socket but I would not recommend removing those bolts with the IP in the car. I have read of people managing to remove and reinstall them with the IP in the vehicle but having done it on the bench all I can do is tip my hat to them.

[br29029]

I don't think corrosion is the problem, it looks really (surprisingly so, actually) clean. My best guess is I am missing a spring:

http://www.greenbaypartsworld.com/vw/pi ... c05405.jpg

The spring to the right of the red arrow, it is compressed. Would that cause my problems?

[hagar]

br29029 would you post more pictures of pump ? you are dealing with govenor. Pump looks clean .

Taken the pump to a BOSCH shop for assembly is one choice.. Sounds to me you did the big O ring on distributer block right.

Got a feeling that you are not a beginner ?

hagar

PS : Seattle is a good location to get help. newbies please do not lift top of pump to look see .The throttle arm iis connected using a very very small "C" clip .very difficoult to get back on.

[hjalbert]

I don't think that is his pump, but I could be wrong. here is a link that might help with the function, (and while you have got it apart you could do the mod)

http://www.vwdiesel.net/forum/index.php?topic=24497.0

[82vdub]

I don't think that is his pump, but I could be wrong.

That pic is one from the general IP re-assembly thread, not his specific pump.

[br29029]

hagar: I'll see if I can get pictures of the pump up tomorrow. I'd rather not take it to a Bosch shop, that just takes all the fun out of it! and I'm on a bit of a budget besides. I am not much of a beginner, I grew up on a farm and nowadays farming is synonymous with diesel mechanics.

hjalbert: thanks for that link! it was insightful. It shows that the throttle arm (governor spring assembly) does not have a spring to the right of the throttle plate (not sure if thats actually what its called, what I was talking about in my previous post).

So when I took off the top of the pump I actually managed to drop the return spring into the body of the pump, brilliant, I know. But I managed to get it out, but my magnet stayed in (I had just epoxied a rare earth magnet to a coat hanger, and it got stuck on the way out). I didn't want to leave it in there, and I was feeling stupid, so I took the distributor block all the way out.

All of the pump internals look great, and everything seemed perfect. No gunk, no shavings, nothing that would indicated a problem. And to be honest, I don't think it'll be too bad to get back together... knock on wood.

One question though, is the lever assembly supposed to just flop around? There are three plates, one the furthest to the right that is controlled by the max fuel screw and sits against the two springs in the head, the middle lever that is attached to the "governor spring assembly" (isn't that a misnomer?) and the third plate that is actually pushed on by the governor. The plate furthest to the right sits tight, but the other two plates flop around, isn't there supposed to be a spring between the two?

(sorry, thats vague without pictures, I'll try to take some soon!)

Thanks a lot for all the help.

[hjalbert]

im pretty sure that the spring does go there, he just did not have it on in that picture, if you look at some of the other pictures, it shows the spring. also, in this diagram (ignore the fact its a turbo pump) you can see everything broken down. it also shows that spring.