7MGE Head Gasket replacement

69ho

New Member
May 17, 2013
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0
Huntsville, AL
I am replacing the head gasket on my '89 Supra and noticed on re-assembly that the top surface of the rear timing cover is above the block deck surface from around the middle of the cover over to the left side and at or below the surface going the other way. Is this normal? Where should the surface lie; at or below the block deck?
 
Oct 11, 2005
3,815
13
38
Thousand Oaks, CA
I can confirm. From the factory the two don't line up perfectly. Mine was on an angle and above the block for half the length as you describe. Engine had never been apart. The stock gasket seems okay with this.
 

69ho

New Member
May 17, 2013
10
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0
Huntsville, AL
This engine had been rebuilt by the previous owner and I was concerned that the cover was installed minus a dowel or locating device of some sort causing it to be positioned above the deck. I have not been able to find a good illustration that shows me what locates the cover. With the cover above the deck on this side the head will not sit flat on the block deck. The old head gasket was showing quite a bit of leakage in the area of the #1 cylinder fire ring. To me the top cover surface should be co-planar with the block deck or if the tolerance stack up the wrong way it should have been desinged to end up below the deck. After reading your response 3p141592654 I am not sure if I go to the trouble of removing the cover inspecting and re-installing that I will be any better off??
 
Oct 11, 2005
3,815
13
38
Thousand Oaks, CA
I am not saying it is a good thing, just that the factory did not seem to be controlling this too well. If it was me I would have it decked flat (which is what I did).
 

BrandonW

New Member
Jun 25, 2007
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N.J.
p1959854_1.gif


pulling from another thread
Don't forget the RTV on the two places on the top of the rear timing plate too.

Speaking of the rear timing plate, was it machined at the same time as the block? (I hope so) The top has to be even or just slightly below the block deck surface for the MHG to seal.

don't know if you are going metal head gasket or oem but I would personally want them to be even especially if its already sitting slightly higher