Q45tech: questions on Q45 valve covers

[StarPD]

I note quite a few posts about leaking valve covers. I had the problem on my '94 Q45t.

Is there anything that can be done to prevent it?

Can the valve cover fasteners be snugged periodically to prevent this?Or does age-hardening of the gaskets cause the valve covers to be distorted by doing so?

Are the fasteners reasonably accessable, or does getting to them involve the same hassle as changing the gaskets?

I remember on my big-block Corvettes having to replace the factory cork gaskets with neoprene ones, then having to regularly re-torque them to prevent seepage, but the fasteners were in the open and clear, and it was easy.

Finally, can we expect the same problem on VK45s as on the VH45s?

[maxnix]

Torquing in to iron (big block Cheby) is a lot different than aluminum.

The elasticity fails, hence they need to be replaced every 60K- 80K.

Don't know if the gasket material was chnged on the VK, but I suspect not.

[StarPD]

Torquing in to iron (big block Cheby) is a lot different than aluminum.

The elasticity fails, hence they need to be replaced every 60K- 80K.

Don't know if the gasket material was chnged on the VK, but I suspect not.

But I had aluminum heads on my last two big blocks, L-89 and L-88

Valve covers were chromed sheet steel though.

Are VH-VK covers aluminum?As best I recal,my VH were, haven't looked at my VK yet.

Are you saying VH-VK gaskets need to be replaced every 60-80k?That sure is a major hassle based on what I read here and the estimate I got ($1300!!!!) to replace just one on my VH, which I didn't do.

[Q45tech]

They usually last a little longer than 70k say 100k depending on driving suitations and local ambient and oil composition and the 90 day change interval.

We change both valve covers and throw in labor for new spark plugs for $575 or $650 with Active or TCS [extra labor required] adds parts costs.

We have things apart so we recommend a few other services [fuel filter, air and oil change all fluids, clean plenum and TB/injectors/EGR.

You cannot own an old Q cost effectively if you must pay $120per hour dealer labor and do all the necessary things to maintain as brand new.

I remember 12 years ago when we started at $45 per hour now at $85 dealers were at $65 now $120.

[StarPD]

They usually last a little longer than 70k say 100k depending on driving suitations and local ambient and oil composition and the 90 day change interval.

We change both valve covers and throw in labor for new spark plugs for $575 or $650 with Active or TCS [extra labor required] adds parts costs.

We have things apart so we recommend a few other services [fuel filter, air and oil change all fluids, clean plenum and TB/injectors/EGR.

You cannot own an old Q cost effectively if you must pay $120per hour dealer labor and do all the necessary things to maintain as brand new.

I remember 12 years ago when we started at $45 per hour now at $85 dealers were at $65 now $120.

I am religious about my fluid changes/flushes, but am trapped into using the dealer. I know of no good reliable and knowledgable indepedent shops in Phoenix that are familiar with Infiniti. The dealer quoted me $1300 (!!!!) to replace ONE valve cover gasket!!!!! I believe the interval for olugs on F50 is now up to 90k. When I have that done, I'll try to get a break on valve cover gaskets then too.

Once again though, are the valve cover fasteners acceible, and will snugging them extend the time interval to change them?

Thanks

[maxnix]

I know of no good reliable and knowledgable indepedent shops in Phoenix that are familiar with Infiniti.

Once again though, are the valve cover fasteners acceible, and will snugging them extend the time interval to change them?

Greg does. AZHitman.

Well, you missed my implication on the aluminum head. One torque on new rubber cushioned washers is all you get, without penalty of stripping out the thread receptaclet.

[StarPD]

Greg does. AZHitman.

Well, you missed my implication on the aluminum head. One torque on new rubber cushioned washers is all you get, without penalty of stripping out the thread receptaclet.

I'll look him up.Thanks.

Sounds like there's no way to avoid the dreaded valve cover gasket debacle.

[capncash]

This is a relatively easy job and any half *** mechanic should be able to do this for half that price.

[maxnix]

any half *** mechanic should be able to do this for half that price.

Last person I want to work on my car.
Modified by maxnix at 7:51 PM 3/24/2007

[capncash]

Yeah but for a valve gasket, what could someone screw up?

Hey max, any secret getting this EGRC BP Tube off the EGR valve? I am having trouble getting this BIG nut to budge?

[maxnix]

Oh, stripped bolt receptacle threads.

PB Blaster. Next time, I willl undo it at the bottom where it connects to the exhaust manifold first.

[capncash]

sprayed it with wd40 and it came right off!! OK now ive got everything out of the way except for that one tube that comes across the middle of the valve cover. Is the valve cover really suppose to come off with that tube still on there?

[3Q Jay]

the egr tube can remain in place if it is loosened slightly at the bottom (exh mani) nut to allow it to 'swing' just a bit.evrything else has to come off the top, including the coil packs and the harnesses to them, and the secondary air hoses (the ~5/8" dia pipe under the TB). don't mess wit the CAS or the VVT solenoid.

[capncash]

I just found an old post that said to put an extension in that tube and actually bend it upward a bit to allow for clearance. I got the EGR tube out of the way, but the tube that comes under the plenum across the middle of the vave cover is the one i am talking about. I guess i will try to bend it tommorow.

[capncash]

So before I go gorilla on this tube. Is this the correct procedure? Just bend the tube up with a ratchet extension?

[Unnatural1]

I remember 12 years ago when we started at $45 per hour now at $85 dealers were at $65 now $120.

Damn, my dealer's only $86 an hour. But then again we're not an Infiniti's dealer...but we do sell Lincoln's. And we charge the same labor for them as we do the Mercury's and Mazda's. I guess I'm working on the wrong cars?

[Unnatural1]

So before I go gorilla on this tube. Is this the correct procedure? Just bend the tube up with a ratchet extension?

Typically, anytime you are considering bending something, or hitting it with a hammer, it is the wrong procedure. But, without having done it myself I can't say for sure. However, I will have that pleasure soon enough as my valve covers are leaking too.

[capncash]

Bending the tube out of the way with an ratchet extension did work. Bending it back to where it was supposed to be to allow room for the air intake and a rubber hose was a pain in the A$$.

Overall the job was pretty straightforward. Some things I learned the hard way:

Removing the brackets that hold the wiring harness allows more room for easier removal/installation of valve cover.

Bend the EGR tube as little as possible to allow valve cover to slide out.

There is a 4 or 5 in hose on top at the front of the valve cover. I cut it off figuring I would just replace it. It is a specialty hose with different sizes on both ends. I had to zip tie a larger hose on until I can find a replacement.

Remove the hood (especially if you are tall like me). My back is still hurting. I should have taken the 10 minutes to do this, if you are novice like me be prepared for 6 hours bent over car.

Dont be overwhelmed by nuts/bolts/electrical connections. Just keep up with everything and it is fairly obvious where everything goes when you are putting it back together.

Use zip ties to hold things out of the way when removing valve cover.

Good luck!

[maxnix]

I'll add one thing I haven't seen anyone mention yet.

There are about 36 special washers that seal the studs that the nuts hold the valve covers down. On my cat, the special collared rubber or more likely neoprene material on my 60K VC were very aged, so I replced them as the old ones were compressed and hardened, thus affecting torquing of the nuts. The part number is 13268-97E00 and the are listed at $4.77 each. Joe's price is 25% off.

I will post pictures of these special wahsers and how to release the clips for the driver's side harness as soon as Wes loads tehm onto Q45.org.

Pay special attention in the FSM to the two stage tightening sequence, and I must highly recommend using an accurate torque wrench also. Failure to observe the sequence and tighten equally will doubtless result in an uneven pressure and an sooner leaking VC gasket.

Finally, anyone note that the nut closest to the firewall is not indlcuded in this sequence, or is it just me?