Injection Pump Questions

[Tmarkle]

So I'm new to VW diesel. I just bought my first one a few weeks ago, a 1985 Jetta 1.6D, and I love it, but recently it's developed a decent fuel leak. My best guess is the front seal because it runs down underneath the timing cover. Oddly enough, it doesn't lose prime, but when running leaks a pretty good amount of fuel, it has dropped my fuel mileage to 30mpg. So my first question is, can a mechanically inclined person reseal the pump on their own? Second question, is it safe to run for a little while until I get the seals and the time to fix it? I've heard it can cause premature timing belt failure and my belt looks pretty solid so I don't really want to bend valves. Sorry to ask a question that I'm sure has been asked before, but I want some direct answers. The alternator quit on me the other night so I'm hoping maybe to just take one day to fix these things and get her back on the road, as my Cummins doesn't get very good fuel mileage. Thanks in advance.

[colby]

The main shaft seal can be done with the pump in the car, but you'll need the sprocket puller or some puller to get the pump sprocket off. I would stop driving it, fuel leaking on to the belt will cause the rubber to soften and inevitably snap, which is not a good thing, because then you'll end up with the bent valves and stuff. I've heard that if the pump is really worn, the shaft will actually wobble to some degree which can cause a new seal to go out as well.

Any diesel injection shop that sells Bosch parts should be able to get you the seal. You just have to be careful when removing it not to scar the shaft or mar it up, because the new seal will leak if you do. The shaft has a keyway as well, so be cognizant of this when you remove the pump sprocket so it doesn't go flying off and disappear, its commonly called a woodruff key.

I resealed mine in an 84 Jetta with 300k miles while it was in the car, didn't take too much time. Pulling the seal out is probably the worst part (taking care not to damage shaft, etc). I believe the new seals have a spring on them as well on the back side so you want to be sure to wet the lip of the seal before seating it in there and not to bend the lip of the seal, should be easy enough to do I would think.

My recommendation would be to stop driving it, get the seal, and reseal it. Shouldn't take more than a couple of hours to do.. I tried the standard 2 and 3 eared pullers but it didn't work, lucky for me, a shop down the road had the correct tool and the owner let me use it to do the job but I believe there may be some home brew methods that work really well too, and you may find them on this site under the specialty tools thread.

Keep in mind you will need to set the engine at TDC before you remove the timing belt. Lots of people suggest locking the camshaft as well, which will require a new valve cover gasket and something the correct thickness to fit in the slot at the end of the camshaft. Retiming can be somewhat of a pain, its easy to get one tooth off on the IP, and sometimes it feels like the thing just wont go back together but with some screwing around you can usually do a pretty good job. I've used a jewler's screwdriver and a flat tip screw driver as a lever to tension the belt. Overtightening the belt will cook all kinds of bearings, so something to be aware of as well.

[Tmarkle]

Thanks so much for the reply. I don't think the shaft is worn out and wobbling because the timing belt tracks perfectly, apparently if they are worn out they make the belt wobble also. Is it normal for the pump not to lose prime with this seal going bad? I would think it wouldn't want to start in the morning but she will start without being plugged in all the way down to 5 degrees Fahrenheit. Would this be the only seal that would cause fuel to run down under the timing cover?

[TylerDurden]

If the fuel is leaking while running, and not losing prime, it may be the governor shaft seal. That seal is under pressure when running and close to the front of the pump. The mainshaft seal usually sucks air and causes rough running.

It's not too hard to reseal, but takes attention to detail and cleanliness.

[Tmarkle]

Would the governer shaft leak down under the timing cover? Doesn't seem like it would to me but like I said in kind of a newbie to VW. What's the process to replace that seal?

[greg lousy]

where exactly are you finding diesel? It could end up in the timing belt area from any number of places. It could run across the IP mounting plate or just down the side of the engine. ... injector lines,... any seal on pump, fuel line .
Yes, the mainshaft seal can leak while the pump still primes and works.
I would idle with the timing cover off and look and find exactly where the leak is before doing anything

[TylerDurden]

This is the governor shaft:


Some info on the seal kit here:
viewtopic.php?t=11314

[Tmarkle]

Is replacing the governor shaft seal pretty straight forward once the pump is off the car? From what I've seen just doing a full reseal is probably the best route to go. What would be a good estimate for USD price to have a shop just reseal the pump? I cant quite eat whatever $850CA is in USD for a Giles pump build right now, even though I would love to.

[Tmarkle]

The diesel drips down the passenger side of the motor and from my observations appears to be coming from the mainshaft seal. When idling with the cover off (which is it a good idea to leave it off or is it best to just leave it on the car?) it will spray diesel on the firewall.

[Tmarkle]

Sorry for being offshore, but I did get the front seal replaced! Being it was my first time doing such a job it seemed a bit tricky, but in hindsight it was straight forward. But now a small new problem has come forth. I'm losing prime somewhere, the front seal is obviously no longer leaking, but after sitting for a day or so the injector jumper between cylinder 1 and 2 will be dry. Any ideas of why this might be? Gunna try a different type of fuel line and see if the new stuff isn't right, as it's very rigid. Starts hard but after start up runs like a champ.

[TylerDurden]

Pretty common for those little lines to leak. When the car sits, the fuel tries to flow back to the tank and draws air in through any tiny gap (even those too small to leak fuel under low pressure).

[Tmarkle]

Pretty common for those little lines to leak. When the car sits, the fuel tries to flow back to the tank and draws air in through any tiny gap (even those too small to leak fuel under low pressure).

They are slightly damp around the bases. The only effect like I said is a slightly hard start. Trying to decide if I should just ignore it and run it lol

[TylerDurden]

I'd replace them. They won't get any better, and if you hit any cold weather, they can leak air a lot and your engine won't start.

[Tmarkle]

I'd replace them. They won't get any better, and if you hit any cold weather, they can leak air a lot and your engine won't start.

Yeah I'm going to replace them. It still started for me at 25 degrees Fahrenheit the other day but it wasn't very happy with me lol

[Fatmobile]

Use clear lines if you can.
As you've noticed there are a few things you can learn by watching how the air or fuel flows in those line that will help you diagnose a problem..
I just grab some 1/8" vinyl line. It fits a little loose at the beginning sometimes but tightens up after a few heat cycles.