Valve cover gaskets.

[eric m.]

Is it hard to change the valve cover gaskets? Approx. how much time will it take? And do I have to take alot of stuff off to get to it?

[Drake57]

On a 1992 it is a good sized job - the coil packs and plenum must be removed - I did the driver side, but not the passenger side. Having done one side, I could do it now in probably six hours. It is very nearly as much work to do one side as it is to do both.

Many of the engine ventilation hoses (and there are many) were rock hard, shattered like glass, and had to be replaced. For some of these you may use bulk heater hose, others are molded and must be OEM. You would also probably want to replace the 8 rubber rings that seal the spider to the lower runners. I also replaced all of the vacuum lines with auto parts store bulk vacuum hose.

Has anyone reused the rubber rings mentioned above? I replaced mine, but the originals still seemed intact and pliant. I'm not sure it was necessary.

There are several easy to find, easy to read writeups on VC and plenum removal and replacement in this forum, I highly suggest you read up before delving in.

Can someone who has resealed the passenger side VC on a 90-94 style Q45 please please tell me if it is necessary to remove that part of the AC low pressure line which dresses just above the rear of the passenger side valve cover to be able to remove said cover?

Thanks! Drake.

[maxnix]

Eric.m you need to complete your profile and tell us which MY and trim of Q45 you are driving.

The VH41De is a different proposition from the VH45DE.

My passenger side gaskets on the VH45DE were quite brittle and broke easily. The lower O rings always should be replaced to avoid even the tiniest leak.

You will need a good socket set, and a 1/4" drive will help you a couple of times. Metric Allen and torque wrenches also. You must have all gaskets on hand!

[oldmako]

Tons of info on the site regarding VC gasket replacement. Since I enjoy being a rabble rouser and contrarian I'll toss in my two cents.

IF (Big if) they are only leaking a minor amount, consider just tightening them. Be very careful, that mother is aluminum. Use your head, not your triceps.

I bought my car last winter and mine leaked. I performed the above and they have not leaked one drop since then. Of course they might leak tomorrow....perhaps not. I've cheated it for 13 months and 24,000 miles. I live in a cold spot in winter and have no garage. To change them out is pretty much a 6-8 hour job depending on whose thread you read. No way I was going to do that in a condo parking lot in winter.

If they leak again, obviously I'll have no choice but to get all cro-magnum and tear into it. But until then, I saved a couple of hundred bucks and my 50 year old, worn out fat-guy lower back.

There are those here who will take umbrage, blaspheme, fulminate and express shock and dismay, but it worked for me. "Members standards vary" I doubt any will volunteer to schlep over and do the job for me, so I'll see to it when that time comes.

If you decide to do the work yo' own seff, you might consider doing a whole bunch of other stuff while you've got it all torn up....plugs, hoses, belts, etc. As mentioned above, there are a lot of brittle bits on the top of these engines...so it might be an appropriate time to bite the bullet and knock a bunch of stuff out. Access is a wonderful thing and hard to come by in these cars.

[maxnix]

Theh problem with tightening them is the specified torque is set with compliant rubber in mind. When the rubber is brittle, you can easily torque past the 5 ft. lbs. and strip the head receptacle, which is a far worse problem.

[oldmako]

Like I said, use your head. Worked for me.

[Q451990]

On Q45s with rubber rocker cover gaskets (after 1993) I agree that gently tightening the screws is a possible short term solution to the leak. The danger is getting someone who uses a 1/2" drive ratchet with a 16" breaker bar on the end of it and tightens it "til it stops" which would be more like "til it pops" - so the "use your head" comment is critical here.

I don't agree with Drake57's comment that the plenum has to come off. Unless you remove the runers as well, you aren't gaining any extra space. The only reason you would need to pull the plenum is if you break a rubber hose feeding one of the rocker covers that terminates in the valley. For the most part Nissan stubbed everything out with metal to avoid this.

Heath

[maxnix]

True, the plenums never need to be removed.

But let me say if no one has been under there in the last 50K -60K, you are fooling yourself that there is no deferred maintenance!

Removing the plenum and addressing these areas makes this a once every five years job, at worst.

[Drake57]

Heath,

IIRC I just did not see any way to be able to remove the cover without removing the plenum - it's been a few weeks, but some of the metal ventilation tubing on the driver side seemed to be above the VC, such that it would interfere with replacing the cover.

I own a 1992 with RTV seal, and I felt (and still feel) it's necessary to lower cover without a lot of side to side motion, such that rtv will remain sufficiently in place to seal. Also some of my rubber ventilation tubing had to be replaced, so I guess I should say in my case it was necessary.

Has anyone removed/RTV resealed/replace passenger side vc without removing low pressure AC line near rear of same cover?

Thanks, Drake.

[Drake57]

True, the plenums never need to be removed.

.

Say what? Never?

[maxnix]

Say what? Never?

Never to replace the VC cover gaskets.

[maxnix]

Has anyone removed/RTV resealed/replace passenger side vc without removing low pressure AC line near rear of same cover?

Thanks, Drake.

Yes, on a 1995. Not fun. One needs a 14" extension and a 10mm wobbly to get the rear #8 nut. Luckily, I have extra ratchets so I could dedicate one to it so I didn't have to remount it during the 3 stage tightening sequence.