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TR4/4A Head gasket won't lay flat

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bammons

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I searched but did not find the answer. I just installed new ARP cylinder head studs and went to fit the head gasket. It will go over the studs but will not lay flat. When I push down on half of it it pooches up at the other half. When I try to push it down there then the pooch goes to the other end. It is a Lucas gasket that is recommended for the 87mm cylinder/piston kit. It is a composite type with a silicone applied. I very lightly scraped at one of the holes at the end as that seems to be where the problem is and it appears to be metal in the middle so I don't think I can enlarge the holes to allow it to go down. It appears if I put the head down on it, it would cause a wrinkle. Any suggestions? Bruce
 
When I remove either the two front studs or the two rear studs it does lay flat but when I screw the studs back in when the stud is almost all the way in it pooches up. Should I just take two of the studs out and put the cylinder head on and then screw them in? ARP says to hand tighten the studs into the block anyways and them torque when the head is on and the nuts/washers are hand tightened. Or do I just have a bad gasket?
 
The old gasket is copper and it does fit. I believe I could put the head down and then thread the last two studs thru the head and into the block but I am concerned about creating metal particles when the threads rub against the gasket although I could pull the head back off and clean it. Maybe I just need to call BPNW and discuss a new gasket.
 
You will have to carefully open up the end holes to the inside, using a sharp exacto knife, deburring tool, or file. You may even be able to trim it with a small set of sheet metal sheers.
 
Ok guys I did get it by continuing to screw the two end studs repeatedly after placing the gasket over all the others and working the studs in (if that makes sense). The gasket did not appear altered or damaged by doing this ( I was getting ready to use a file though). Now the embarrassing part - I was so happy that I got it flat and to be able to get my head on I forgot to put the tappets in and went ahead and torqued the head to 110ft lbs as per ARP instructions. Well the gap here in this line is for all you out there to have a laugh break and wonder why somebody so unqualified is building a engine. So now I need to know if I removed the head and put in the tappets then retorqued the head down on the same gasket (remember it is composite with silicone) will that be OK or do I now need another head gasket? Bruce
 
I am laughing because I had to remove my torqued head immediately after also. Not that I forgot the tappets but because I got in a hurry and didn’t polish and debur the tappets before installing them. Once I got the rockers on and tried to adjust the valves I found the tappets were sticking. So I didn’t chance it and bought another head gasket. Same one you have so that was a expensive mistake. Got to ask , did you get the correct liner protrusions exactly the same across all four? See my post below on liner protrusion. The sticking tappets wound up being a good thing as I remeasured my liner protrusion after I removed the head and found I was under spec. I had measured them without first putting the head on with an old used gasket and torquing it to 105 pounds and then remeasuring. Makes a difference I found out.
 
The correct answer is that you will need a new head gasket. I have been in your place more than once...so much so that now days I am in no hurry to torque the head during a build. I normally bring it down and torque to about 20fltlbs, and then move on to other things, coming back later to finish the torquing. Once the gasket has been to the full torque crush, it will never have the sealing power of a fresh gasket that has not been crushed.

That said...if money is really tight, you could probably get away with coating both sides of the gasket with WellSeal and there is a 95% chance it will seal just fine.
 
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John - As usual your answer makes sense. I know different types of material would react differently and I was hoping that with the silicone sealing lines that maybe they would not stay "crushed" and would reseal fine. I am new to this though and have the rest of the body to restore and would not like to find that whenever I finish this that I would have to turn around and remove the head again. The other things you said about not being in a hurry are a lesson I will take to heart. I do agree that there is a decent chance that I could make it work but I respect your knowledge and will spend the $64 (yeah not cheap) to replace it. Thanks for your answer and I hope you got a chuckle out of the newbie mistakes I make.
 
It's not always a "newbie" mistake. If I go too long between rebuilds I end up making the same newbie mistakes as an olebie!
 
Old Yankee saying: "Measure twice, cut once".
How many times have you put the distributor cap back on and left the rotor sitting on top of the valve cover or worse, in the gutter on top of the fender where it could be crushed by the falling hood? The truth now.
 
pdplot said:
Old Yankee saying: "Measure twice, cut once".
How many times have you put the distributor cap back on and left the rotor sitting on top of the valve cover or worse, in the gutter on top of the fender where it could be crushed by the falling hood? The truth now.
Click to expand...

I still forget, only thing I have gotten better about is I do make the great mental leap from "why doesn't it start" to "did you put the rotor back in?" Faster than I used to.
 
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