rolling coal in netural

[lo-vw]

So I did a timing belt swap and now I throw black smoke out at high rpm's

When I did the swap, I locked the pump in place like your are suppose to, and marked the timing belt and gears. I transferred the marks to the new belt, checked all the timing and put back on.

Car runs and drives exactly the same but now blows black smoke.

Any idea? I also changed the oil at the same time.


I can have it in neutral and just floor it and it shoots out black smoke.

[Fatmobile]

Did you check the cam timing?

[Quantum-man]

Lock it all up again and put the old timming belt back on. If the smoking disappears, then it is a timing issue. If it doesn't then it iis a timing issue ....

Down to the belt, in the former and you in the latter...

Both cured by adjusting the pump. [ A dial reading with old belt in place before removing would have been useful. ]

[lo-vw]

pros and cons of just leaving it how it is?

good thing I read this before I took the trash out as the belt is in there.

Timing has to be spot on, but I bet from over the years the other belt stretched some and the fuel timing is out of sync a hair.

[the man 53]

If you didn't loosen the cam and properly tension the belt, there is the problem. The mark and pray method usually doesn't work as there is no good way to tension the belt without something moving. Make sure to always rotate the engine with a 19mm socket 2 revolutions before touching the starter. If you redo the job correctly you will probably notice you are off from where you should have been.

[CarlosA]

I agree with what he said ^ i`ve never been able to get a really precision time without loosening the cam sprocket and tensioning by hand. I would say there could be some slack in the old belt and all sorts of possible "wear" variables.

[lo-vw]

Correct me if I am wrong but the only way to get a "precision time" is to loosen the PUMP and use a dial indicator. Mechanically the crank and cam cant get out of sync because they are keyed on the corresponding shaft correct ( like a gasser)?

I mean they can get out of sync tooth wise but the sprockets cant move on the cam or crank.


Engine runs and drives great still, I swapped out the fuel filter and took my intake foam thing off and it seems to be better, but still a tiny bit of black smoke.

I know im dead nuts belt and tooth wise, I counted and re counted, then spun the crank twice.
She fired RIGHT up no hesitation or anything too.

Im new to diesels but my guess is its the pump needs adjusted now, but I could be wrong.

[bscutt]

No the cam pulley is a friction fit and has no keyway on the diesel engine. You set the crank to TDC, loosen the cam pulley, line up TDC, the pump mark, and the flat cut on the #4 cylinder end of the cam such that is is 100% parallel to the head - I have a piece of metal I cut to fit in the cam end but there are a few different techniques to get that parallel relationship. Maintain that alignment and tighten up the tensioner and cam pulley bolt and you're good to go. This is oversimplified but the fundamentals are correct. So it's essential that you get the cam times correctly to the crank and then you can tweak pump timing to get performance and mileage as desired

[lo-vw]

Oh good to know!

Maybe I will do that this weekend.
Just take the top TB cover off, set car to TDC, lock pump into place, take valve cover off, loosen tensioner and loosen cam gear, install that metal piece/make sure cam is flat to head, tighten tensioner, tighten cam gear, reinstall everything and test it out.

Is cam gear bolt one time use?

[TylerDurden]

Just take the top TB cover off, set car to TDC, lock pump into place, take valve cover off, loosen tensioner and loosen cam gear, install that metal piece/make sure cam is flat to head, tighten tensioner, tighten cam gear, reinstall everything and test it out.
Is cam gear bolt one time use?

Pretty much...

Cam Pulley can be stubborn. A puller to add tension and a whack with a brass mallet is suggested.
Avoid torquing on the flat plate when tightening the cam bolt, the slotted end of the camshaft breaks easily.

[lo-vw]

the gasser cams usually have a hex or spot to put a wrench on the cam. is that how to tighten it/break it loose?

[bscutt]

Cam bolt is not a one time use. There are a few ways to hold the cam pulley still to loosen and
retighten the bolt. I just put a breaker bar through one of the pulley holes and hold it against the top of the head which has worked for me without head damage but the best way it so have a tool (see tools link on this forum) to hold the pulley still. I may make one of those some day.

[82vdub]

I have always been successful at loosening and tightening the cam bolt by simply locking the IP first with the pin. It's the first thing I do when I lock the IP.

[lo-vw]

Sounds good thanks guys!

Does anyone rent or know where I Can get that dial indicator screw in attachment to time the pump?

[DeadEye]

I got mine on ebay. There like 50.00 , for 70 you get the dial gauge plus cam lock tool and ip lock pin and spanner tension wrench. I also got the tension gauge for another 55 but it a not required tool.