Valve cover gasket replacement on the 4.0 v6

I did it a while ago, took me 2 days cause I'm lazy and it was my first "major" mechanical job and i found out i needed a more than a gasket, i took off the valve covers and the entire inner side was covered in buildup that looked like half metal glitter and half ground up graphite.

 

That is the Secondary Air Injection Reed Valves. The pump is on the passenger fender well. It injects air into the exhaust system to heat up the catalytic converter faster.

 

Hey everyone. I have a spark plug well on the passenger side that had some oil in it, so I am going to replace the gasket. Couple questions for anyone who might like to help a a guy out:

1. The driver side seems fine (for now). If it were you would you do both or just the side that has the failure? From the way it looks passenger side might be a lot easier and less time consuming to do on it's own. If it were the bothersome side I would no doubt do both, but it just seems pointless if that other gasket hasn't failed..., yet. Tell me to quit slacking and do the right thing if you want.

2. Here is where my newbness will shine, but the pieces that connect the spark plug o-rings together and to the gasket, do those stay attached for the install or do they get snipped? My logic tells me things flopping around inside a place where other things are moving about doing enginey type stuff is not a good idea. But people much smarter than me designed this and some of you folks who have done this work will know more than me, so please enlighten me.

3. And lastly I saw the mention to add some rtv to the area where the timing, head, and VC meet? Is the convenient arrow in the pic I have added below that spot? I mean it looks like there is a gap in the gasket surface so again, logic tells me that is the place. If not can someone point me to the right place?


Please take it easy on me. I am not an idiot, I am just very literal and I overthink everything, especially when it comes to the old gal. Last gaskets I replaced were on a small block chevy, so this is overhead cam, spark plugs through the valve cover business is alien technology for a guy who hasn't had to wrench much on vehicles since I started driving Toyotas.

 

If it was my truck, I would probably only do the passenger's side if the driver's side is OK. Since it's a V6, you can always go back to do that one if it ever decides to leak.

But I understand the people who prefer doing both, since you've already done half the work to get to the driver's side.

 

Yeah it even looks like there is a little RTV left over from the original gasket. Just pick that piece off and put a dab right there with some new RTV.

 

And leave the rings attached. You're not supposed to snip them apart...

 

I would do both, but that's just me.
I look at it like replacing just one ball joint or one shock.

I don't want to have to tear back into it again

 

I would def do the driver's side. If one leaked already, that means the other is likely to go as well pretty soon. You're already there, just do it so you don't have to go through all the hassle again.

 

Hi, did you have to drain the coolant before you remove the upper intake? Thanks.

 

Just finished this project on my 2006 4.0 about 75k miles. No problems, its pretty straight forward took about 4.5 hours. Had oil leaking off both sides onto the exhaust, causing smoke after exhaust got up to temp. Old gaskets were brittle and end of life. Tricky clip at back on driver side, ended up just pulling the bolt. Replaced plugs also, gaps were huge. Universal joint for socket and several adapters and extensions helped. This video is a good start, I was done with passenger side before he got his secondary air intake gizmo off, had to fast forward to get torque specs. Much easier not having to mess with that.

https://youtu.be/FJN7EAk-GV8

 

Stupid question, what kind of RTV were you talking about? Is it the hardened glue to make a gasket maker or lubrication?

 

Nothing special.
Just standard gasket maker.

https://www.permatex.com/products/g...x-ultra-black-rtv-silicone-gasket-maker-5-oz/

 

Toyota calls it seal packing.
The rest of the world calls it RTV.

 

I got you. But I'm still confused since we are replacing an old valve cover gasket with a new one why would we need to apply RTV? just curiosity.

 

Because there is a gap where the timing cover, head, and valve cover meet.
The gasket itself isn’t sufficient enough in those 2 spots.
See link below.

https://www.tacomaworld.com/threads...et-replacement-and-more.479612/#post-14597085

 

Got you. I'm working on replacing my old gasket now and I'm glad you answered very fast. Thank you for your explanation sir

 

Just remember. Bolt and Nut (B) are in inch/lbs.
That is, if you actually torque them to spec.
I’ve never torqued a valve cover bolt. I just go by feel.

 

*EDIT* Lol, I should have scrolled further! Looks like this has been covered and possibly beaten to death on placement of RTV sealant!!

I know your post is from 4 years ago, but just wanted to mention that there should be 2 places on EACH valve cover that needs a little bit of RTV sealant. Your arrow is correct, but there should also be a spot directly above your arrow that needs a little bit of RTV sealant. There should be another slit that looks exactly like the one you put an arrow on that is at the top of the valve cover that will need some RTV sealant. Other than that, it looks good! I have been needing to do this on my 2009 Tacoma Prerunner for awhile now, but just haven't gotten to it yet. I am planning on replacing both of my VVT solenoids and filters, so I might just tackle the valve cover gaskets as well, since I will have them exposed. Happy Wrenching everyone!!

 

We did the passenger side valve cover gasket in November of 2023. The center spark plug well was leaking. Took some time with the videos and photographs to remove and replace everything. We tied it all together into a YouTube video.

https://youtu.be/Z3qyjJbFPLE?si=wEtN9sCR5MzBocwP

*note 1: if you need to do the drivers side gasket, you'll need another source

*note 2: our truck is a 2014 with the air injection pump. That's a little PITA to remove and reinstall. We tried to take good videos of it so maybe that will help someone in the future....