2004 Toyota Highlander Valve Cover Gaskets

Valve cover gasket replacement on a 2004 Toyota Highlander 3MZ-FE 3.3L V6 Engine

[@markoswald2637]

A couple of things, it looked like the bolts were shouldering before pulling tight, so you may have needed new crush washers, the torque in the Toyota manual says 96 in-lbs (8ft-lbs), also Toyota specifies that a Toyota 08826-00080 Seal Packing Black is used in the corners and a few other points to prevent leaks, but really nice to see a genuine video, so many videos of this it says remove the rear cover bolts and miraculously they are out. Well done for showing it how it is, as;o there are two half moons in each head at the right-hand end they need to be pulled and sealed as well.

[@damnedhumanrace]

Thanks very much for this reply. I didn't use the Toyota seal packing black but I did use RTV. Misapplication of the RTV is one of my leading theories to explain the leak, along with the 69 vs 96 inch lbs on the rear bolts. Definitely did not remove those half-moon pieces but I don't think the leak is coming from there. Good note on the bolt shouldering- if I end up re-doing the rear cover I'll spring for all new bolts. It will take me a while to talk myself into making another attempt at this

[@donnamcdougall1963]

10 out of 10 for tenacity , watching the drama with the bolts was edge of the seat stuff

[@Sci-Mon1]

the bolts for the valve cover need new washers. i learned that the hard way when working on my 1MZFE

[@damnedhumanrace]

Is there a way to replace the washers without replacing the entire bolt? I should have just not re-used the bolts, is what the consensus seems to be. Tough lesson to learn

[@Sci-Mon1]

@@damnedhumanrace you actually just add washers onto the existing ones. if I remember correctly it was 2 washer added to each bolt. I don’t exactly know what but these bolts are very fragile. I’m going to have to do this same job on my 04 highlander. I gotta say you just have bad luck my dude when working on cars.

[@damnedhumanrace]

​@@Sci-Mon1 I think if I take that cover off again I would just spring for new OEM bolts. They're only a few bucks apiece. Part of me just never wants to turn another wrench on this car

[@adiladilalhmady106]

The water in the end can be from Washer Water Pump

[@damnedhumanrace]

it's (some type of) oil not water

[@adiladilalhmady106]

Great work...but why don't you use a WD 40 for the screws to soften them before opening so they don't break, perhaps?

[@ayoutubechannel613]

What symptoms did you have? Was it leaking oil on the exhaust and smoking? Was the engine whining? I think my gasket may have given way recently on mine.

[@damnedhumanrace]

Noticed some oil on the backside of the engine. Start of a slow fail and figured it was time. Never got to the point where it hit the exhaust. No engine whining. Good luck!

[@adiladilalhmady106]

If the issues is like this, we will stop opening such old engines because it is a problem and a waste of time. Greetings ..

[@damnedhumanrace]

in retrospect maybe not the worst idea

[@MattL.-KE0SAW]

About how many hours would you say it took to replace the gaskets minus your issue with the bolts?

[@damnedhumanrace]

removing two or three issues I think the pure gasket replacement probably took me 10-12 hours? Hard to estimate because it was spread out over several days. Definitely wasn't rushing. Knowing what I know now I could probably go back and get it done in 6-8?

[@MattL.-KE0SAW]

@damnedhumanrace just finished installing the plugs, coils and gaskets. Front one was simple, the back took me the rest of the day. The gaskets got caught on the rear passenger side and I didn't realize it was off until I was almost done tightening the bolts. I took off the cover again reset the little piece of gasket, and then retightened the bolts making sure that the gasket was in place. But that's enough for tonight! I'll put the rest of that together tomorrow and take it on a test drive then. I think I'd rather do the timing belt again then the back gaskets! my back and knees are killing me from leaning and climbing over that van!!

[@damnedhumanrace]

@@MattL.-KE0SAW yes I agree timing belt was an easier job than that rear bank alone. I lost feeling in parts of my hands for weeks from supporting my weight on the engine in awkward positions. I was paranoid about the gasket slipping out or getting caught like yours did. As far as I could tell it went in ok, but access/visibility is so tough in some places it felt more like hope than a confirmation when I was checking it

[@MattL.-KE0SAW]

@damnedhumanrace exactly! That entire back valve cover is done by feel alone and nothing else. I think a blind man would have an easier time than us with that one!