Valve seals replacement

Normand

Veteran Member
Joined
Nov 8, 1999
Location
Near Montreal, Quebec
Hi all,
on a '96 B4 TDI Passat, what is the correct
way of changing the valve seal, officially and a
jack of all trade way to do it when you don't have
all of the required tools as VW would prescribed.

I need to change those seals to get rid of the
heavy blue smoke problem i have in morning start
the engine as now 400,000 KM will do the timing belt at same time.

Thanks in advanced, Norm.
 

redtdi96

Veteran Member
Joined
Dec 11, 1999
Location
bridgewater, new jersey,08807
My gut tells me since there is no vacumm on the diesels the seals are not a problem. This was a problem on gassers after going down a hill with the throttle closed. You then have a vacumm built up which will suck in anything it can...like oil from the seals.

If you really want to do seals you need to presurrize the cylinder, remove the cam and buckets and fashion or buy a tool.
When you replace the cam ....... use only hand tighting on the cam caps/bearings and equally tighten eaach cap a tiny bit (tiny-tiny) or you will crack the head. Never use a srench till you aaaaare sure that the cam is tight!
 

20ValveT

Veteran Member
Joined
Oct 4, 2002
Location
Canada
I would check to make sure the seals on your turbo aren't what are causing the problem. Like redtdi said the engines barely have any vacum so the chances of it pulling oil in is slim. Are you sure that its oil that the engine is burning? Smell it on start-up. It could be you have a leaky injector. Anyways try these before you start ripping the head apart, its a big job to do when you not sure what the problem actually is.
Good Luck
 

RIP TDI

Top Post Dawg
Joined
Feb 16, 2000
Location
Santa Barbara, CA
TDI
'15 GSW SE 6MT...... '01 Golf GLS 5MT.... '96 Passat Variant....
If valve seals are the problem, the most likely conditions under which you will get blue smoke on startup will be when you restart a warm engine after its been sitting for an hour or so. Oil definitely will drain down past worn seals/guides by gravity alone...especially in these engines which have a pool of oil below the cam.
 

Drivbiwire

Zehntes Jahr der Veteran
Joined
Oct 13, 1998
Location
Boise, Idaho
TDI
2013 Passat TDI, Newmar Ventana 8.3L ISC 3945, 2016 E250 BT, 2000 Jetta TDI
If you want to change the valve seals its not all the bad. The best way is to rig up compresses air to keep the vavles closed in the cylinder. Or you can set the engine at TDC and use the piston deck to keep the valve closed.

If for some reason you drop that valve...You be in deep juju


Pull the cam, remove the lifter with a magnet and now your at the keeper. Compress the spring remove the two keepers and out the spring and cap come. This will expose the valve seal. They are pressed on so you may have to work them loose. I think they sell a special set of pliers to grip the seal below and around the valve guide.

Reinstall, compress the spring and insert the keepers and lifter and move to the next valve. Not bad at all to do.

I do however STRONGLY suggest to cover EVRY hole in the head because if you drop something its going to the oil pan
. It wont hurt anything if it gets down there but you will be out one part that is needed for assembly purposes.

The suggestion about the turbo seals is a valid one. I would inspect the turbo outlet for clean areas on the back of the wheel. This indicates where fresh oil is being lost.

Since the TDI is turbocharged The positive pressure will prevent oil from going down into the intake and exhaust. If the smoke is present when driving and not just at start up then investigate new nozzles from Kerma or a possible compressor seal or even turbine seal leak.

DB
 

GoFaster

Moderator at Large
Joined
Jun 16, 1999
Location
Brampton, Ontario, Canada
TDI
2006 Jetta TDI
Blue smoke upon cold-engine startup? At 400,000 km?

I betcha your injectors are shot and your glow plugs are shot, and the valve stem seals are fine.

The '96 doesn't appear to have the "glow plug monitoring" fault code implemented, by the way. I had a completely dead glow plug and the dreaded MIL never whispered a thing about it. You could have a set of shot glow plugs and never know it, on this particular model.
 

GoFaster

Moderator at Large
Joined
Jun 16, 1999
Location
Brampton, Ontario, Canada
TDI
2006 Jetta TDI
The other thing to check is the coolant temp sensor calibration. Just this past weekend, I discovered that mine is off more than it used to be ... it's showing 75 degrees C with engine fully warmed up, and it always used to be around 83 or 84. (Gauge shows 90.)
 

Normand

Veteran Member
Joined
Nov 8, 1999
Location
Near Montreal, Quebec
First, let me thank you for your response.
As you mentionned, the problem would be other than the valves oil seals, likely to be the turbo seal and perhaps a leaky injector.

Question: -how do you determine that the turbo as falty seal, how to replace.
-same for injector. as for injector, do refer to the black hoses connecting the injector.

When the engine is warm, there is no smoke at start-up. On cold start-up, the colder it is outside, more smoke will appear.

As i hooked vagcom i noticed that the timing is way off, at the bottom of the graph bellow the line, could this have an bearing on the smoke.

Thanks again, Normand.

[ February 03, 2003, 12:46: Message edited by: Normand ]
 

weedeater

Top Post Dawg
Joined
Mar 17, 2001
Location
Reston, VA
TDI
Jetta, 2001, Baltic Green
Leaky injector is when it's internal valve does not seat properly. Extra fuel then dribbles out causing smoke.

Leaky turbo seal burns motor oil and you will see the level drop. This is dangerous on the intake side since if it completely lets go, all the motor oil will be sucked into the engine and you get a runaway condition and perhaps hydrolock causing bent/broken rods.
 
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