1.6 NA diesel pump leak

[dieselwagen]

noticed diesel fuel leak on the backside of the diesel pump [opposite the timing belt]. (4)17mm nuts are tight. the underside of the pump is wet.
it tried to wipe the pump as dry as i could and will look again tomorrow.
where else could be a possible source of the liquid fuel leak.?

[Jettage1]

How about the side of the pump toward the engine?  The cold start lever o-ring goes bad, so I've been told.

[dieselwagen]

How about the side of the pump toward the engine?  The cold start lever o-ring goes bad, so I've been told.

checked it again today
the cold start lever and the advance mechanism cover on the opposite side [towards front of engine] is still dry today after i wiped the whole pump down yesterday.
yet it was seeping raw diesel in between the cast-iron distribution block and aluminum pump housing.
used the search function and also ventured over at vwdieselparts.com and there's a 99.9% possibility the big O-ring might have called it quits.
i got a feeling this leak have also caused the coolant bypass hose to deteriorate in untimely manner a few days ago.

[Jettage1]

Glad you found it, but offering my condolences on the necessary repair.

BTW, where in CA are you?  I spent the first 30 years of my life in L.A....

[jtanguay]

if its not a major leak, you could try running some 2 stroke oil to help swell up the seals.  just don't drive in front of some prissy prius driver... :lol:

the timing plug could be leaking.  i heard that you can take the washer off, heat it up with a torch? and then replace it, and re-torque.  i'm not sure of the torque value though.  it might be in the FAQ.

[Op-Ivy]

Sounds like it's that main O ring leaking. My pump did the same thing. Eventually one of the lower radiator hoses became corroded from diesel and burst. Fortunately (I guess...) it was in my driveway. :lol:

[Quantum TD]

How about the side of the pump toward the engine?  The cold start lever o-ring goes bad, so I've been told.

checked it again today
the cold start lever and the advance mechanism cover on the opposite side [towards front of engine] is still dry today after i wiped the whole pump down yesterday.
yet it was seeping raw diesel in between the cast-iron distribution block and aluminum pump housing.
used the search function and also ventured over at vwdieselparts.com and there's a 99.9% possibility the big O-ring might have called it quits.
i got a feeling this leak have also caused the coolant bypass hose to deteriorate in untimely manner a few days ago.

Yep, that'll kill your hoses. Pull your pump off and have the whole thing resealed. The other seals will begin to seep eventually. I've tried the ATF trick. I don't work. The only thing to stop it is a total reseal.

Andrew (libbybapa) reseals em, as does a guy on ebay. Either way, it has to come off to replace all the seals. You can try to replace just the distrtibutor head o-ring, but you run the risk of catastrophic internal pump damage if the cam-rollers fall out of place. It's best to replace that seal with the pump off, and the cast iron part pointing up in the air.

good luck.

[Doug]

I tried the reseal trick but ended up chasing the leaks around the pump till I finally bit the bullet for a rebuilt, calibrated pump. The engine is easily making 20% more power with much better acceleration from low end as well as better midrange power. It was worth the money. I just wish that I spent it first up instead of hopefully dreaming that a few Orings were going to get me by.

[dieselwagen]

i was actually reading a pretty good write-up by Andrew [libbybapa] regarding the large O-ring "in-car" replacement. but there's no telling what kind of condition the rest of seals are in.
so it may be to my benefit to consider a full re-seal (or a re-built) at this point. and i can just have it done by a diesel pro, because i'm truly worried of effing the IP if i try to pretend i know what to do. well at least it will give me the opportunity to refresh the timing belt/ water pump at the same time. car is showing 197,000 miles on the clock right now.

MUCH THANKS for all the responses and well wishers, my '86 diesel just needs a little hiatus and hibernate for a while.

[jtanguay]

i just want to add that my 1.6TD had a major fuel leak.. it was a pretty good dribble.  right onto the lower coolant hose.  it leaked for about 150km of driving.  and the hose was fine.  the funny thing is... the old diesel which swells up the seals in the pump was changed to ULSD (which does not have the aromatics that swell up the seals) and so even though my pump leaked, it did not harm my coolant hoses.  i ran the car for another two years without any problem from that hose.  i did examine it from time to time and it never bulged whatsoever.

the ATF trick in the pump might not work, but i suspect that two stroke oil would.  if that doesn't, then you could always try power steering stop leak.  that stuff is designed to swell up the seals inside the whole steering system, and with the P/S pump being so intolerant to foreign particles, must mean that it should be okay for the injection pump.

getting the pump rebuilt properly costs quite a bit, and is the best route to go, but not everyone has that kind of money.  running the stop leak could help extend the life of the pump long enough to save for a proper rebuild.  and remember that most reseal places you see online are simply that, and do nothing to bring the pump back to OEM specs.  IMO you're probably better off doing it yourself in that case.

[dieselwagen]

the ATF trick in the pump might not work, but i suspect that two stroke oil would.  if that doesn't, then you could always try power steering stop leak.  that stuff is designed to swell up the seals inside the whole steering system, and with the P/S pump being so intolerant to foreign particles, must mean that it should be okay for the injection pump.
.

thanks man, i'll try these and see if the seals will swell. otherwise i am gonna contact one of the local dubber here in northern calif. who has a spare pump i can practice on. maybe he will even trade up for my 2 ton cherry picker i don't need right now.

[jtanguay]

the ATF trick in the pump might not work, but i suspect that two stroke oil would.  if that doesn't, then you could always try power steering stop leak.  that stuff is designed to swell up the seals inside the whole steering system, and with the P/S pump being so intolerant to foreign particles, must mean that it should be okay for the injection pump.
.

thanks man, i'll try these and see if the seals will swell. otherwise i am gonna contact one of the local dubber here in northern calif. who has a spare pump i can practice on. maybe he will even trade up for my 2 ton cherry picker i don't need right now.

i think you'll need to run the pump straight from the power steering stop leak.  just putting a can of that in your fuel tank will probably not be enough.  get a small fuel filter on the in-line going to the pump from the bottle.  it's very similar to running a can of diesel purge through the pump...

[dieselweasel]

I've been in the same boat.

Right after Oct 2006 when the fuel switched to ULSD around here my pump started to leak at the distributor head seal.  It dripped onto the coolant bypass hose which eventually started leaking (didn't burst though which I was thankful for).  Not wanted to spend the money on a rebuild and not able to afford the downtime, I resealed the distributor head in-car, using Libbybapa's method.  Worked great.  The only leak that developed after was at the internal seal in the LDA.  Planning on pulling that car off the road soon, I took a length of vinyl tubing and attached it to the LDA vent then ran the tubing down to near road level so as to spare my hoses from the evils of diesel fuel.   :lol:

[scj3230]

I am having the same problem too.  My pump is leaking from the back somewhere.  When I go to start it in the morning there is a small space on my driveway where it has been leaking fuel.  I am not sure if its because of the cold weather that makes the seals shrink or if I just have bad seals and am delaying the inevitable.  If I am delaying the inevitable, are things only going to get worse?  I haven't noticed any performance decreases and I still get good mileage.  I might as well wait as long as I can and then send my pump to Giles up in Canada and really get my money's worth!  Maybe if someone could show me where Andrew [libbybapa]'s page is on how to do the in-car replacement of the o-ring it would help out a lot.  Any other suggestions would be greatly appreciated as no one in Utah will touch my old diesel!

[burn_your_money]

I'd try the ATF trick first. It's the fastest, easiest and cheapest. A rare combo.

Things will eventually get worse with your pump. It might happen overnight or it could take a few years. There isn't really a sure way to tell. I don't think changing the head o-ring in car is a good idea. There is a lot of stuff that can fall out and you wouldn't even know it.

If it's leaking at the back of the pump, it's probably the cold start lever which shouldn't be too bad of a seal to replace. You do need to take the pump off the car for that one though. Just make sure that no dirt gets in the pump. I've taken apart a couple pumps where people have changed the advance seals and gotten a few pieces of dirt in there. They get caught between the piston and housing and wear it out, effectively eliminating your advance.