Cam shaft thrust O rings leak?

[Justsammer]

Hi folks,
I recently purchased a 1994 Delica, and the speciality mechanic I took it to told me that I had a slight engine oil leak from the "cam shaft thrust O rings" at the back of the engine, and that those seals need to be replaced. I was told this is very common with these vehicles. One speciality mechanic told me it can only be done by dropping the transmission and engine, so as to get access to those o rings, and that it's very labor/time intensive and a very high cost to do the job. Another speciality mechanic told me that they do it with the engine in place, for a fraction of the cost. Then the first mechanic told me that the second mechanic was essentially lying, and that the second mechanic probably only reaches up and spreads silicone over the old seals, crosses their fingers, and tells you it was done.

So I'm looking for some guidance on this...
Has any body done this job themselves?
Does the engine need to be removed?
Can you tell me where to find info on doing this job myself, if it can be?
Any additonal info would be very appreciated, like; is this important to fix, what are these camshaft thrust o rings?


Or even just telling me how to search for this info on this forum would be helpful, as I have tried every combination of the words "Cam shaft, o rings, seals" etc, and can't seem to find the right subject, even though I've been that this is one of the most common issues with these vehicles. So can you advise on how to search for this topic, what words to use?

I'd like to just hear from private owners please, not professional mechanics, so as to not add to the confusion.

much appreciated, I'm thankful to have this community of help.

1994 L400 Delica V6 gas 3000

cheers

[thelazygreenfox]

Hi J
I'm a moderator on this site, long time (3) delica owner and a 3 litre gas owner presently. I do virtually all of my mechanical work including the oil leak on the cams, timing belts and spark plug changes.

Sounds like you have been given some confusing stories about the cam leak.

The entire job is a pita, doesn't need the engine removed, only lowered 2" and done by someone with patience and dexterity. Any backyard mechanic can do it but it must be done right with the right tools and lots of time. it's usually only the left hand cam cover that leaks but check both for oil residue before you start.

It's just an oil leak, shouldn't affect the normal running of the engine but will make a mess on your garage floor and leave oil spots on the street where you park eventually. IMHO you can't remove the bolts with the engine in place and the cooling water tubing which must come off first to do the cam repair or the o ring at the front of the tubing.

If you look under the van on the drivers side to the top of the engine you can see if there is an oil leak. You can run your hand back from under the hood to feel the oil and feel how tight it is to work on.

CCA in Coombs removes the engine to repair the leak and do the rest of the import changes to the V6. That is the easiest way to repair the leak.

If the oil leak is tiny don't change it till it needs be done. Plan it to be done when you change your rear water hoses, plugs, valve cover gasket, timing belt/water pump or other major job. In the meantime you can build up your list of tools, ratchet wrenches, blocks, jack stands and a hydraulic jack and start doing tie rod, ball joint or other jobs..

The O ring at the front center cooling line (between the heads) should be changed at the same time because it leaks after being removed for the cam oil leak repair. The air box on top of the engine needs be removed to change that o ring. So you can start to see how extensive the repair is.

Buy all you parts ahead of time, they won't be available when the job is being done. O rings are proprietary and need be purchased from a local dealer ahead of time.

Plan on the van being up on stands and blocks in a dry place (garage) with good lighting for more than a weekend. Ask a good buddy to help you and plan on feeding him. Don't give him booze till after the job is finished. LOL

Mitsu should be shot for this design f#$%up. Most of the V6's need to have this leak repaired.

There's lots I haven't mentioned so be prepared for a big job.

Don't attempt this repair unless you have the van safely held on 6 ton,4 ton jacks, sturdy blocks and a strong hydraulic jack to lift it. Your life is at stake if the engine or front end falls on you.
Good luck
MD

[thelazygreenfox]

I have to ask why this work wasn't done before you bought the L400? Did you buy from the Japanese auction block or a dealer? There's lots of initial import repairs that need be done when bringing in a vehicle from outside the US. Headlights, alignment, tires, brakes and inspection all need be done before you can drive it. The cam oil leak repair is a minor part but can be done before the Deli arrives at your door.
MD

[dr_airtime]

Related. First time L400 diesel owner. Owned an L300 before. 24 months into import from Japan on my L400 (Gen 2 1997 diesel)

Lost quite a bit of oil in my last 5000km oil change run. Maybe a litre...more? The main thing that wasn't done on import was the valve cover gasket since there was no visual evidence of leaking at that time. Don't fix unless broken. Now you can see the classic oil seeping out in last 6 months. My questions are:

1) Is it likely only the Valve Cover Gasket that could explain this amount of oil leak? There are likely some other common seals that leak at back of engine for sure (maybe around Turbo and the Cam Shaft O rings discussed here), but only the valve cover gasket is likely to explain that amount of oil loss?

2) Is there is anything else worth doing that is a once-in-van's-lifetime replacement when the valve cover gasket is replaced and mechanic working around there?

Thanks - using a local mechanic but just want to check other's thoughts here.

Andre

[dr_airtime]

Heads up that apparently it is a "cone" (cone shape?) at the back of the valve cover gasket that is responsible for the most common and largest oil leak. Other culpruit to look out for is the exhaust gasket (at head-exhaust intake connection near top of head on left of engine) when you open it up the the exhaust gasket is more likely to just let moisture in than leak oil.

So if you have an oil leak and you can see some seeping around valve cover gasket at least try replacing that first if it isn't original....then see if you still leak.