TDI Front crankshaft seal nightmare

[Mavrick]

Trying to resolve an extremely heavy oil leak coming from the front seal on a 2004 BEW TDI Jetta. Our tech installed a new seal, which leaked, and tried another one, which also leaked. I took it apart myself a third time and replaced the crank seal again. Crank snout was slightly worn, and was cleaned up with fine emery cloth. We are using a PTFE seal, which is being installed dry and the last time I let the car sit for 4 hours before starting it.

This car has just under 600,000km on it. After each seal replacement, the car will run that day with no signs of leaking. I drove this car/had it idling for 8 hours without any problems. After the vehicle sits overnight, the seal leaks (badly) just idling in the parking lot shortly after starting it. The first two failed seals had torn on the outside lip. I'm wondering if maybe the crank is moving around, worse when cold, and causing the seal to fail.

Im a VW tech and have installed 30+ crank seals, even more cam seals. Never a single problem. I even took my time on this one.

We're putting an engine in the car now, but I wanted to see if anyone has had a similar experience.

 

[Jesse_Boyer]

I had a similar experience when I swapped my bad engine for a junkyard one that was allegedly good.

After a few minutes of running, I could see oil around the belt, all over the timing cover, and leaking out of the seal. The engine had consumed the main bearings and the crank sunk down into the main caps, stretching the seal, leaking oil.

 

[jetta 97]

Trying to resolve an extremely heavy oil leak coming from the front seal on a 2004 BEW TDI Jetta. Our tech installed a new seal, which leaked, and tried another one, which also leaked. I took it apart myself a third time and replaced the crank seal again. Crank snout was slightly worn, and was cleaned up with fine emery cloth. We are using a PTFE seal, which is being installed dry and the last time I let the car sit for 4 hours before starting it.

This car has just under 600,000km on it. After each seal replacement, the car will run that day with no signs of leaking. I drove this car/had it idling for 8 hours without any problems. After the vehicle sits overnight, the seal leaks (badly) just idling in the parking lot shortly after starting it. The first two failed seals had torn on the outside lip. I'm wondering if maybe the crank is moving around, worse when cold, and causing the seal to fail.

Im a VW tech and have installed 30+ crank seals, even more cam seals. Never a single problem. I even took my time on this one.

We're putting an engine in the car now, but I wanted to see if anyone has had a similar experience.

Piston rings are possible bad and blowing pressure inside engine .
Crank seal leak is the first sing of worn piston rings.

I may be wrong but I have seen it on older VW Diesels this problem.

 

[Ski in NC]

Take some wood blocks, or whatever, and put a big up-force on the crank pulley/damper. If bearings are worn, you will see crank lift up with the force visibly. Quick zero cost test.

 

[JettaTDIBlack]

Take some wood blocks, or whatever, and put a big up-force on the crank pulley/damper. If bearings are worn, you will see crank lift up with the force visibly. Quick zero cost test.

I assume this can be done without the engine running?

Sent from my LGMP260 using Tapatalk

 

[JETaah]

Lo

Take some wood blocks, or whatever, and put a big up-force on the crank pulley/damper. If bearings are worn, you will see crank lift up with the force visibly. Quick zero cost test.

I've dealt with the same and it was found that the #1 and 2 bearing had spun and routed out the bearing saddles and caps. Too expensive to fix...time to replace the engine.
What tipped me off was to observe the balancer bouncing around at idle ever so slightly. The owner had made mention of the oil pressure light going on intermittently

 

[C Squared]

You may also consider a speedi seal if all is OK. Pretty common deal. Over time any seal will wear the surface it rides on. This is a very thin sleave for the crank that gives the seal a new surface to ride on. I assume there is one available for this application. I've used them in lots of situations.