Head gasket question from a newbie

1

1955effie

Junior Member
Thanks for letting me join. My engine is leaking antifreeze. Block is .006 low in the center , edges are fine can’t get feeler gauge under the steel square. Is there a gasket on the market for this situation. It’s a 5.5 head and it’s checks out flat
 
Mike's sells the 'Premium A Head Gasket that might do the trick (said to be the best), but it states that you should use the 'B' gasket for a high compression head (5.5.1). If the head is flat then the top of the block should be 'surfaced' as it must be where the problem is. That extra compression is an issue with both surfaces not being flat.
 
All gaskets have a specific thickness and a compressed thickness. As long as You still get a good amount of compression in the low spot you should be good.

Sent from my SM-G930V using Tapatalk
 
Any more to the story? You are not running a Model B engine, are you? What is a 5.5 head? Put the gasket up against the head and see how it fits.

Charlie Stephens
 
Thanks . I’ll give that a try. I live in Vt and there isn’t any place left around here that is doing any of that type of machining that I am aware of. This was my Dads car and I would like to get some of these issues taken care of. He never got to drive it much and he said for me to enjoy it. One step at a time I guess
 
It’s a 29 block. The 5.5 to 1 ratio head is from my understanding the equivalent of a B or police head back in the day. I think some of the issues have been the old engine studs were weak because after letting it sit it would have to be torqued again and I haven’t been able to figure out why. It’s only driven about 10 miles a year since we rebuilt it. Currently has 51 miles on the odometer. It is fine for awhile and then all of a sudden it’s leaking again. New studs and gasket have been ordered and I will install them with the new nuts etc and see what happens. It’s not really a big job to remove the head etc but I would like to get a handle on this and call it done. What I can’t understand is why it’s fine for a while then leaks again. It’s not like it’s stepping up the compression that much over a stock head
 
I drove it after the last install about a mile or two as I was told to do . It was done again after sitting around for a couple of months because it started leaking again but the car was never started in between time. That stopped the leaking for around a month or maybe a bit more but it started again. That’s when I tried to tighten it back down and found that number 8 wouldn’t tighten
 
1955effie said:
I drove it after the last install about a mile or two as I was told to do . It was done again after sitting around for a couple of months because it started leaking again but the car was never started in between time. That stopped the leaking for around a month or maybe a bit more but it started again. That’s when I tried to tighten it back down and found that number 8 wouldn’t tighten
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What do you mean that #8 would not tighten, did it not move when you reached 55#? Your goal is to reach a point with additional running and retorquing to have the nuts not turn as you come up to 55.

John
 
Threads on the nut were stripped on number 8 in the torque sequence. Tried another nut ( I own a body shop) from my bolt and nuts bin. Same thing threads on the stud were bad so that’s why I decided to remove and replace everything new . I’m torquing to the recommended 65 lbs as the new style head manufacturer suggests.
 
Sadly, no one makes a gasket that is thicker in the middle Is your straight edge a bonified machinist straight edge? I think your question might be " how much time between: Drive to around 160F & park it and let cool. This is one cycle:C-H-C.Do the re-torque 1 cycle completed. Wait as long as you want but the next time you drive it, Its going to be cycle #2. And so it goes until 4 re-torques.
 
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When you remove the old studs use a tube type wire brush made for an electric drill and clean the holes in the block for the studs. Blow them out good and be sure to check that they are what I call blind holes. Meaning that they do not go into the water passages. Make sure that the surface of the block and the head are super clean. I use denatured alcohol for the final cleaning. After that put a small amount of anti cease on the studs and install. If any anti cease squeezes up around the studs clean it off.
Spray your new gasket with copper coat spay three times. Do not apply it too heavy, just light coats and let it dry to a good sticky tack in between coats. Don't rush it between coats as you want the solvents to flash off. After that install the head and torque to 25 lbs, 35 lbs, 45 lbs and finally 55 lbs. Personally I don't think you need to go to 65 lbs. Allow it to rest for several hours or over night and re-torque again to 55 lbs. Now this is where others may have issue but after you get to this point without putting water in the engine go ahead and start it and let it run at idle for 20 seconds and only 20 seconds. Use a timer or watch to make sure of the time. It will barely feel warm immediately after shutting it off but the temp will continue to climb for a while after shutting down. Re-torque the head again while warm. Allow it to cool down and check the torque again then. After it has cooled down start it again without water, run for another 20 seconds, shut off and repeat as before.
The reason for doing this is if you do have any issue with loss of torque before it settles in you will not have any water seeping into the gasket area that will cause issues.
After repeating this process two times then go ahead and fill it with water, start it and bring it up to temperature. Shut it down and immediately check the torque again while hot and let it cool. Go ahead and check the torque once, twice or more as it cools. Yes it sounds like a lot of torquing but really you can not torque too many times but only torque too much (meaning too many lbs of torque).
Keep checking the torque until it finally settles in and no longer moves. Sometimes it is a fairly quick process and sometimes it takes a while. Keep at it until you are satisfied.
 
1955effie said:
So what’s the suggestion as far as the torque durations and how many times before it seats itself
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Every 50 miles or so until the nut no longer move when torqued. I place the wrench on the nut, make a note of where the handle is. I then "crack" the nut loose and retighten again noting if the handle is in the same place as when I started. If it is, then fine, the torqueing is done. If it has moved then another 50 miles.


But that is just me, there are different ways, mileages etc. on how to do it.
 
You don't say where in Vermont you are, but there is a very good machine shop in Albany, NY that can mill either your head or block. Universal Machine on Broadway in Albany. You can do what you want, but if I had a head that was .006 out of flat, I'd have it machined. It's a simple job for the right shop and your gasket troubles would be over...

Frank

I just re-read you first post. Sounds like the block is out... I'd get a reading from the shop on what to do, but I still think .006 is too much...
 
Thanks everyone for the information. Dad and I put this one together back in the early 1970’s . I was a kid back then and we didn’t have a heated garage or electricity and it was my job to. “ hold the flashlight “and as anyone knows the winters up here in the NE can be rather cold so I wasn’t really paying attention because I just wanted to get back inside where there was heat. He passed away in 2014 so I’m doing most of this by memory and what information in available on the internet. BTW not much is posted via YouTube etc and most machine shops up here are closed up. So it’s trial and error until I figure things out. As I said before I’m a body man (self taught mostly) by trade so mechanical issues are a bit out of my realm. There isn’t a Model A club left here either as most have either moved away or passed on . Again I thank everyone for the information and letting me join your page. I’ll post progress or failures in hopes that it may help someone else along their build.
 
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