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Good morning guys. This past weekend I decided to take it upon myself to replace my leaky valve cover gaskets.
Everything was going well (including the removal of the dreaded EGR nuts) until I tried to lift the plenum off. I removed practically everything that is connected to it (or so I presume), including the 6 bolts and 2 nuts.
I can not for the life of me get the plenum to release off of the lower intake. I spotted some rtv on the mating surfaces, which leads me to believe the previous individual in the area used rtv to seal it...
Would you guys be able to take a look through the photos and let me know if I missed a bolt or something that would prevent me from removing the plenum. Also any tips would also be greatly appreciated. Not sure if maybe warming up the mating surface with a heat gun would soften up the RTV?
I've spent more time than I would like to admit on this.
Thanks in advance!!!
'95 4Runner 4WD 3,0L V6
http://imgur.com/a/oosU4Top Side Driver Side Passenger Side Detail view of RTV between mating surfaces
The large (18mm?) hose to the PAIR valve (in your photo, the hose clamp has been slid up, so it looks like you've addressed it) is difficult to disconnect. That's the hard part for me. But IF that were your problem you'd be able to lift the plenum about an inch.
(If the PAIR hose IS your problem, I recommend a hot air gun to warm up the rubber. Makes it much easier to flex, and therefore to remove. Be careful; a hot air gun can get way too hot.)
I am not sure what the hose runs to, but there is a 1 inch hose that connects to the bottom of the intake that is located in the back of the plenum, just under the A on TOYOTA. It was a pain in the ass to get to. It may be the hose that scope103 is talking about, I am not sure. I just know that the hose that I described gave me issues until I found it. It kept me from being able to life the plenum up even a fraction of an inch.
That hose was a pain to budge so I gave up on it for the time being.
Thanks for the tip of warming it up, will definitely give it a try with the heat gun. If this is whats preventing it from being lifted off I would be amazed.
You still have the EGR valve hanging on its vacuum lines; since you've already removed the difficult parts (the big nuts on the exhaust lines) I'd just take it out now.
There is a stay that connects the passenger side of the block to one of the studs on the plenum for the EGR tube. I don't see it, so I assume you have it out.
Notice all the "gunk" visible in the plenum through the hole for the EGR tube. This is a common issue. It's mostly from the PCV system, but enough of it can clog the vacuum ports and even the EGR tube itself. If the EGR tube is blocked you'll fail smog for excess NOx. I don't know why you are removing the plenum, but since you are, I'd consider cleaning the inside of the plenum. I used a bottle brush, paint thinner, and dishwasher soap (don't go nuts; dishwasher soap has very high pH and the plenum is aluminum). I didn't remove the "freeze plugs" in the ends of the plenum, but now I wish I had.
Last, this may be too late, but I hope you made careful notes of what hose goes where. You don't want to be one of those guys posting "where do these hoses go?" Masking tape tags are popular, but can easily be pulled off.
scope103: Thank you for the detailed picture. The main reason for removal is to access the passenger side valve cover gasket in order to replace it due to an oil leak.
-Luckily the vacuum hoses were numbered and their positions noted so that shouldn't be too much of a hassle.
-The amount of gunk (carbon build up?) in the EGR port amazed me. I'll be definitely clearing that up.
-I've been following the FSM so hopefully I didn't miss anything but thank you for posting the link, will come in handy.
I'll post later tonight if the PAIR Hose is what has been my issue.
Consider getting a mortar tub http://www.homedepot.com/p/Medium-Mi...101A/202086173 . Cleaning large parts (plenum, heads, etc.) sitting on the driveway makes a big mess. This will catch it. You can even use it to soak. They're cheap enough to chuck into recycling when you're done, or make a really luxurious powder-room for your cat.
... I spotted some rtv on the mating surfaces, which leads me to believe the previous individual in the area used rtv to seal it... Not sure if maybe warming up the mating surface with a heat gun would soften up the RTV? ...
RTV is not called for, so IF it was used (I can't tell from the picture) that would make the plenum more difficult to remove. Heat would help, but that's a mighty big chunk of aluminum to heat up.
The plenum has a pretty substantial overhang on the passenger side (hence the stay), Putting up/down pressure on the passenger side translates into quite a bit of leverage on the mating surface. If you have the four passenger side (long) bolts out, the two drivers side bolts and two drivers side nuts out, and the stay, there isn't anything else that would rigidly hold the plenum. So it should be a matter of applying careful pressure until the RTV splits.
Haha I owe you guys a beer. After blasting heat on it for 15 minutes and applying a good amount of pressure it popped.
The bastard who worked on this (according to the service record it was a hack job at a local dealship for the previous owner used ONLY RTV!!!!!!!!!!!!!!
Yep, that looks like the correct-sized hammer. At least he got really good coverage with the RTV! Now we know why we DON'T use RTV when Toyota says to use a gasket.
The mating surfaces of the plenum and lower intake manifold are machined flat, so you don't want to scratch them up TOO much. To get that RTV off, get it nice and warm (sunlight might be enough), and try to scrape it off with a plastic tool. The razor blade can cut right through aluminum, so save that for the end.
I realize lighting is an issue, but the insides of the plenum passages SHOULD look like bare aluminum. Not black.
Let's hope your new friend didn't change the timing belt. (Because he might have used thread-locker on the crank-bolt. If he did, you're in for a treat.)
04-03-2017, 06:47 AM
