Hi, All. Just use the last Sat to complete the G37 Valve Cover gasket and Spark Plug Tube Gasket change, here is the update:

1. To clarify, G37 spark plug tube gasket is replaceable, it is sold as a set together with the valve gasket (<$20 a new set for left or right side on ebay, total2 left and right side around $35). So dont waste the money to buy a new valve cover. Only G35 needs to do that.

2. You might want to take this chance to change the spark plugs (in my case the tube gasket is leaking oil into the spark plug tube. Bought the correct Denso plug on Amazon for just $9/pc). If you just need to change the spark plug, no need to remove the cover.

3. Special tool you will need, 12mm deep socket to remove 2 screws of the manifold.

3.5 Disconnect the battery

4. Download the service manual. You have to remove the manifold first, so follow the instruction. The only thing I did different is that I did not disconnect most of the coolant tubes connected to the throttle body, prepare some plastic plug or plastic bag to prevent the coolant leaking out.

5. Use some tape to cover the intake opening with tape to prevent objects falling into the engine.

6. Follow the sequence to remove the bolts of the valve cover.

6.5. Do clean the oil in the spark plug tube even you dont need to change the plugs

7. Use some rtv high temp sealant to enhance the sealing. I use more on the right side, in the left side I only use a little bit.

8. The torque to reinstall the valve cover bolt is in Inch-lb, NOT foot-lb, I almost made a mistake. I suggest use hand tightening is enough to feel it if you dont have inch-lb torque tool.

 

Good info, Ive done my few weeks ago, all 4 gaskets and spark plugs. Rockauto has 4pc like ~35 bucks, dealer wanted to charge 30 per gasket.
Also in case someone already did spark plugs, you dont need to remove them in order to remove the valve cover and replace the gasket.

rtv sealant is also good, I personally didnt use it, I cleaned off old sealant residue.
Also do one side at time, its less overwhelming, I personally took time on it, wanted to make sure I cleaned off all the grease that build up from leaking engine oil. Took me 8 hours.

 

idk man ur rtv is a bit excessive. i hope it didnt start to dry before u put the cover back together

 

does the work instructions call for that much silicone gasket? usually silicone gasket is just used on corners or uneven surfaces. it won't necessarily hurt but it may be a pain in the as s later on if you ever need to remove the valve cover again for whatever reason.
btw good pictures and write up of your repairs.

 

Technically it doesn't only around corners like u said

 

Yes, the RTV is a little bit too much for the right side, the manual says to put some RTV at the 4 corners

 

I did put too much on the right side, and so I strictly follow the manual for the left side, only a little bit for the 4 corners. But I did put some at the back of the tube gasket. I put them back before they are dry. So far no leak.

 

OP, Thanks for taking the time to write this up. I plan on doing the same and thought 6-8 hours as well. I'll use the idea of one side at a time too. I may take time to re-torque everything under the valve cover too. Peace of mind thing after 85K miles and not in that area of the engine often.

 

The driver side is a little bit more difficult. Remember most of the torque is in inch-lb not foot lb, dont over tighten it. I suggest you take out the manifold Friday evening, and take a rest, then you can do the rest on Sat. That will make the work feels easier. The dealer wants to charge $1000 because it is just labor intensive.

After everything is done, boot the engine to "on" only without stepping on the bake (not to start it), let the computer relearn the throttle control for 1 -2 minute, and then turn it off and restart the engine.

 

The time has come for me to do the same Any suggestions on tackling this project? Since intake manifold is exposed, would fuel injector replacement be something to consider? I've never gone this far on any maintenance and I'm more concerned about time overall.

 

Suggestion is that you take it slowly, take picture of all the connections. When you tighten the center screws, keep in mind the torque is in INCH Lb, not Foot Lb, I almost overtightened it by using the wrong torque wrench.

I did not change the fuel injector, but I did clean the manifold valves. Good luck!

 

VERY nice write-up. Nice touch adding the manual pages. Doesn't look too hard. Of course you make it look easy too! My son's G needs this, getting some leakage on the driver side after 150K. Too much RTV? yeah, probably, but what are you gonna do? The tubes it comes in are not exactly user-friendly for making a nice small consistent bead. However, if you want to spend some extra $ and attempt to get that niccer bead, check out the Mercedes stuff below. Even a lot of Audi shops use it for it's ease of use and it's quality and durability.

https://www.partsgeek.com/gbproducts...ad=47433948732

 

What's the best way to tell if you need to do this? What are the symptoms?

 

Oil leakage from the valve covers, you can usually see it with a flashlight. Usually the plug gaskets go out first though (not something that is easy to look at from a quick glance), so if you pull your plugs and or coils and they have oil on them, you need to do it. If you ignore it for too long, it can lead to eventual misfires at high RPMs, and eventually misfires randomly at all rpms. Check Engine Lights will also eventually start kicking on when it starts to misfire.

 

Anyone have any tricks/advice for installing the driver's side? I did mine the other day and got a leak at the front of the driver's side cover. Not much room to move that cover around with all the wiring harnesses in the way. Tore it back down and will do it again tomorrow.