89 c-4 head gasket blown
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Joined: Mar 2015
Posts: 80
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From: Winchester Bay Oregon
89 c-4 head gasket blown
This is a new thread about the teardown of my son's C-4 #7 cylinder has water in it so we had to put the car in storage til he gets money to fix it. He is now ready to have the heads done so we proceeded to take the top end apart. We have been taking photos and numbering parts as I have done any engine rebuilding since the 70's and 80's. We got down to where the intake is about ready to come off. I was shocked to see the intake manifold bolts are T45 TORX.I have never seen that before is it stock? When we took the distributor out I noticed the back manifold corner bolt was not a torx but a regular manifold bolt and unfortunately half the bolt hole was missing as the last owner broke the back corner of the manifold. It is a 89 C-4 so we are in need of one. I suppose since the manifold bolts that were torx were not tight nor were they even it was not a suprise we lost a head gasket. I got all the manifold bolts out but the injectors and fuel rails are still in place but I could not break the manifold loose from the heads. Am I missing something? could I have forgotten something I need to take off? He only gets off one day a week and we have quit for the night. I could use some help.
Gary
Gary
Last edited by wolfer; May 22, 2015 at 09:54 PM.
Melting Slicks
Joined: Jan 2014
Posts: 2,192
Likes: 381
From: Lunenburg MA
Yes, the torx are original. Did you get the two inside ones? It's easy to miss the one back by the wiper motor. If all the bolts are out, it's probably just the RTV put on the china walls (front and back).
Le Mans Master
Joined: Mar 2004
Posts: 5,107
Likes: 171
From: Dublin CA
Yes, the intake bolts are Torx......
. Too bad the original owner didn't save the broken corner...it could have been welded back on without too much difficulty.
If you have all the bolts out of the intake outside edge (should be a total of 12 bolts), then it is likely the sealant holding it in place. Take something like a utility knife and insert it between the front china wall and intake and slowly cut the sealant. You might have to do this several times. Then if you have a large (1-1/2 to 2-1/2" wood chisel, put the chisel between the china wall and the intake and pry upwards. This should break the bond.
If you can't find a intake, you could probably use the same manifold and use the standard bolt that came out of the position and add a round washer (cut off the side if needed).
. Too bad the original owner didn't save the broken corner...it could have been welded back on without too much difficulty.If you have all the bolts out of the intake outside edge (should be a total of 12 bolts), then it is likely the sealant holding it in place. Take something like a utility knife and insert it between the front china wall and intake and slowly cut the sealant. You might have to do this several times. Then if you have a large (1-1/2 to 2-1/2" wood chisel, put the chisel between the china wall and the intake and pry upwards. This should break the bond.
If you can't find a intake, you could probably use the same manifold and use the standard bolt that came out of the position and add a round washer (cut off the side if needed).
Instructor
Joined: Jan 2015
Posts: 124
Likes: 5
From: Cave Creek arizona
There a couple of bolts that are hidden as jv noted. They take an extra long torx or get the proper size torx bit and tape it in a quarter inch drive socket to get to it. When you get ready to reassemble have at least one extra torx bit in the correct size. I broke two during the reassembly.
Le Mans Master
Joined: Mar 2004
Posts: 5,107
Likes: 171
From: Dublin CA
The "hidden bolts" you are referring to are the bolts that hold the runners to the intake. There are two I believe between the runners. Wolfer already has the runners off.
There are only 12 bolts holding the intake to the heads. Six on each side.
There are only 12 bolts holding the intake to the heads. Six on each side.
Thread Starter
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Joined: Mar 2015
Posts: 80
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From: Winchester Bay Oregon
Yeah all the #45 Torx bolts are out. When I put it back together I was suspecting to have to torqe the intake manifold these torx bolts were not very tight. Some did not even pop when the broke loose. I lost number 7 cylinder when I ran a compression check the number 7 cylinder was wet. I got 122# compression in that cylinder but when I pushed the button to release the pressure on the tester it blew milky mixed water and oil all over me. I am thinking because that manifold was cracked and took on water causing the head gasket to give way. Have not got the manifold off yet though. Hope no holes in pistons. What manifolds will work in an 89? I will have to wait to see what is below before I buy a manifold. If you have one let me know please.
Last edited by wolfer; May 23, 2015 at 12:05 AM.
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Joined: Mar 2015
Posts: 80
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From: Winchester Bay Oregon
Thanks we are having a concern about two PCV valves one in each valve cover. Is yours an 89 and was it set up that way? We were originally fighting oil seeping out of the top of both valve covers from the pcv rubber gaskets and the rubber oil fill plug. When the engine got warm and he shut it off it stunk like hot oil. Did yours do that before the head gasket went out?
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