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Intake Manifold Is Off! - Now to fix the hard pipes

7787 Views 110 Replies 20 Participants Last post by  fanatichuman
Finally got the manifold off and mostly followed the ShopLife video on how to do it. Now I can start replacing the coolant and heater hard plastic pipes.

Lessons learned with taking off the intake manifold:
1) Have instructions so you can remember how to put it all back together
2) The last manifold nut in the back was hard to take off because I didn't remove the fuel rail
3) Even after vacuuming the areas near the intake ports I found debris near the holes so I covered them up as soon as I removed the manifold but not fully removed
4) The intake manifold gasket is hard to get out and it is breaking while I try to pull it out.

What is the best way to clean the intake manifold and block? I'm going to put aluminum foil over the CCV pipe and fuel hose to make sure nothing gets in them.


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The last manifold nut in the back was hard to take off because I didn't remove the fuel rail
So how did you remove the intake with the fuel rail attached? I also remove the fuel rail off the fuel line for more room. It's easy with the Quick disconnect connector.
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I tried to vacuum all debris before removing the intake to avoid debris drop in the intake ports and may cause leaking valves.
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This is what it looks like so far. The secondary air vacuum hose hard line broke so I'm just going to use a silicone hose all the way from the back to the cannister. The hoses were falling apart. :-(
You need to tape up the fuel rail metal pipe, or debris got in then you have fuel injectors issue.
Decided to clean the engine a little before I start taking off the hard pipes. It looks better but not prefect.
The Knock sensors cable should be ziptied to the lower hard pipe bracket by the factory boys, but missing in this pic circled in red. Some other hands had been in here before you I think.

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Is the ports section clean enough to put the intake manifold back on? There shouldn't be an oily residue but there are stains on it.
Not ready until using your credit card edges to run along the ports surfaces to clean up it good without creating any scratches.
Should I use a pick with a 90 degree angle to pull the stuff out?
Should not. Use a straight pick instead, and stab the rotten pipe lengthwise, then tilt the pick to pull the pipe into its center, and this will break a good piece off without damaging the aluminum hole. Keep stab and tilt until they all gone, then use the sharp edge of a broken hard plastic rod (or chopstick) to rub out the hole smooth and be safe.
It feels pretty smooth in there but the stains remain.
Are you sure they are stains or pitted from corrosion?
Maybe this is too late, but I would add a thin coat of RTV on the bore and on the O-rings before install the pipe back in.
Both pipes had been leaking many months, so I wonder how much coolant you needed to add per week to top off the tank?
This is what I am talking about - It IS aggressive...a steel wire brush on an aluminum bore...I use it carefully and softly by hand to break up the pipe residue...and then follow with a fine grit buffing wheel. My wire brush is the 1/2 inch diameter size which is much smaller than the hole- easier to control.
I wouldn't use any power tool to clean the bore. Sharp edge of a broken hard plastic rod (chopstick) is what I use to clean smooth the bore. Power tool can enlarge the bore then....more headache.
I'm trying to decide if I'm going to use red RTV after reading this thread. Some people used it without issues and others don't recommend it since it could fall apart and clog up the system. Thoughts?
Any sealant or RTV is fine. The trick is have a thin coating on the bore (as the pipe is inserted into the bore, the O-ring will push the excess glue into the head, so just use a thin layer put more between the two O-rings, and insert the pipe immediately when the sealant still wet).
put more between the two O-rings, and insert the pipe immediately when the sealant still wet
Did I say between the O-rings?

Add thin coat on the board acts as lube for the O-rings to slide in easy.
This pic show the top ring of glue is bad for no good reason: anything beyond the inner O-ring is useless so why anyone added glue there?
On the pipe, don't put any glue beyond the inner O-ring, but add plenty of glue from inner O-ring to beyond the outer O-ring as I marked on the pic, because this glue will not get over the inner O-ring and contaminate the system. Nothing outside of the inner O-ring could get into the engine, right?

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As far as putting RTV in the bore, do I pu a thin coat on the entire length of the bore?
A thin coat on the bore to cover up to where the inner O-ring will reach. There will be just a thin bead stuck to the inner side of the inner O-ring.
Just think about what if it leak after the intake manifold installed back and driving couple days later? I won't take the risk of not using RTV in this case.
Also, after coating the RTV then immediately install the pipe and not wait for it to set.
It pains me to even type this, but I was attempting to use the Dremel with the buffing wheel to do this, and while doing so the buffing wheel fell off and inside the port going into the block (Not the one directly above the water pump). I was able to retrieve the buffing wheel, but not the screw or 2 small washers which secured it.
If you might have any ideas as to how I might retrieve them (magnet didn’t work, and unable to locate with inspection camera) it would be greatly appreciated.
Thanks in advance
No power tool for me in doing this; just a broken plastic chopstick and elbow grease, and not even sandpaper.
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the buffing wheel fell off and inside the port going into the block (Not the one directly above the water pump).
This sounds to be the lower pipe connected to the block behind the water pump.

Unfortunately in B
this upper pipe to the head, behind the Tstat.
and a steel wire brush to clean the bore, ouch?? Won't do that on mine.
Give me a broken plastic chopstick and I will use it instead.
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Curious Sapote, the bore seems to be a lot larger than a chopstick. Somebody above just mentioned using a 16 mm socket long. Care to share a pic of your chopstick trick? :) I am sure you use a round chopstick, but some chopsticks are squarish.
Just break up the chopstick in two, then you will have the broken sharp edges to use for scraping off the bore without worry damaging it. Round or square doesn't matter as the broken edges will randomly give the very sharp edge. I just use the sharp edge like a carpenter wood chisel, pushing it against the bore at an angle to clean it smooth. I couldn't think of what other hard plastic rods could be used for this.

Use the round sharp edge or the sharp corner edges.
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Thanks. But I could be mistaken. Some mentioned using a round socket with fine sandpaper
fine sandpaper wrapped around a socket will take longer to clean up the residual on the bore. Beside, I don't use sand paper as I don't want to enlarge the bore.
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i would think plastic trim removal tools (normally comes in blue color, just like what i have, or red) would be safe not to damage the bore. they come in various angle to retrieve small pieces out. thoughts?
Too soft as a cutting tool. Try to bend these to 30 degrees and none will snap, and also has no razor sharp edges.
Go to Chinese dinner asking for plastic chopsticks and quietly keep them. When bent it snaps with razor edges.
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