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Blew another head gasket...

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Morris

Morris

Yoda
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Perhaps the machine shop just ran a steel brush over my block and told me they resurfaced it...

I don't think my marriage can stand me pulling the motor again. Does anyone have any thoughts on strategies to prolong the life of my head gaskets.

One idea I had is to just keep a stock of these cheap head gaskets on the shelf:

https://www.bpnorthwest.com/.sc/ms/dd/ee/6786/Head%20Gasket%20Spitfire%2072-80

The big problem I see with these gaskets is that the cheap gaskets tend to stick to the head like insanity. It's nearly impossible to get them off. But maybe if I spray them with head gasket sealer, they will be easier to remove?

I dunno... Any advice, wisdom, or sympathy you guys can offer will be greatly appreciated.
 
Why did you pull the motor to change the gasket? Anyway, what sort of gasket (quality) have you been using?
 
I did not pully motor, but I would have to if I wanted to get my block resurfaced. I have been using payen gaskets.
 
Morris said:
I don't think my marriage can stand me pulling the motor again. Does anyone have any thoughts on strategies to prolong the life of my head <span style="text-decoration: line-through">gaskets</span>.
Click to expand...

1. I'll pray

2. We have a spare room.

3. Other than that, I'm coming up empty.
 
Morris,
As I recall you're running a turbo like me. The Payen black gasket has worked best for me. Block and head surfaced, no spray, ARP studs, and Megasquirt fuelling and timing tables biased to prevent boosting over 10lbs. A soft rev limiter at 6500 rpm, hard limit at 7k isn't a bad idea either. They get there fast with the turbo.

As long as you're not bored more than 20 over, there should be enough metal to hold the gasket. What compression ratio are you running? 16cc dish pistons with a 28-29cc combustion chamber is where I'm at right now.

Glen Byrns
 
I recently had a freshly rebuilt 1275 that kept blowing head gaskets, always between 2 and 3. Two went before I got my hands on it. I thought it was a problem with poor head studs as I found after the second head gasket that the torque was not where I expected it to be, and one of the (new) studs stripped when taken to the correct torque. I replaced it with the black Payen head gasket and ARP studs. A few weeks later, same problem.

It turned out that the head was raising in the center just enough to allow combustion gasses between the cylinders, but no oil or water leak. The solution was to surface the head after it was heated in an oven. There are shops that can do this. That cured it. This is apparently a little know issue with some of the 1275 heads. It's the first time I had encountered it, but sounds like you are having the same problem.
 
Gerard said:
It turned out that the head was raising in the center just enough to allow combustion gasses between the cylinders, but no oil or water leak. The solution was to surface the head after it was heated in an oven. There are shops that can do this. That cured it. This is apparently a little know issue with some of the 1275 heads. It's the first time I had encountered it, but sounds like you are having the same problem.
Click to expand...

Wow, that's interesting.
 
Glen. I am running a high compression naturally aspirated 1500.

Gerard, I think a part of the problem is that I cut a little too much off of the head and ended up with a higher compression ratio than I wanted.

Also, IIRC I am at .03 over. I wonder if that could be part of the problem.
 
Morris said:
Glen. I am running a high compression naturally aspirated 1500.

Gerard, I think a part of the problem is that I cut a little too much off of the head and ended up with a higher compression ratio than I wanted.

Also, IIRC I am at .03 over. I wonder if that could be part of the problem.
Click to expand...


I'm a little late on the scene as i read this, I assumed you had a 1275,and i think other did as well, but then you said a mouthful, that threw up a bog red flag with me "I have a 1500", and "I had the block decked". The 1500 engine had what was supposed to be a improved head geasket with extr cylinder fire ring material aorund the bore of the gaskets with recessed area on the block for the eatra fire ring to compress in. Ok most would think, including my self this would be a good improvement to engine to not blow head gasket, but 1500 and TR6 engine with the same block recession have long had head gaskets problems, and one big no-no is excessively decking the block because if you mill more off the block than say a "clean up" of .005-.010" you lessne the amoutn of the recession in the block and this compromises head gasket seal, if you cut too much off the block and the recession is lessen to certian point the head gasket will not even seal anymore.

Not probably what you want to hear, but I betting your block was decked enough to compromise the gasket recession in the block and it causing your head gasket to fail long before they should , it could be worse, and not have sealed at all, I seen this firsthand, my advie would be just repalce head gaskets from time to time or worse, start over another block with good straight block deck. I'm sure this is not what you want to hear, but decking a 1500 block is always a bad idea, because of the head gasket design.
 
If that is the case, can he get a custom head gasket?
 
Whoa, hang on a second Hap you lost me. I thought the thing to do was cut that recession all the way out and use the 1300 gasket. Did I miss something?
 
Sorry, I mistakenly thought it was a 1275 too. I know very little about 1500's.
 
kellysguy said:
Whoa, hang on a second Hap you lost me. I thought the thing to do was cut that recession all the way out and use the 1300 gasket. Did I miss something?
Click to expand...

You would probably have to deck the block somewhere in the area of .060" to get all the recession out and at the point the 1500 piston would stick out of the top of the block. Yes the recession does not work well, and some people building race engine have deck the block enough to get the recession out at which point custom forged piston were made for this modification. Some folks including myself have built 1500 race engine using TR6 piston, but that a lot of deck like over a 1/4" and you dangerously close to the freeze plugs in the rear of the block.

here's the real issue with decking a 1500 block somebody, this, hmm, I deck the block .020-.030" to get the comprsion up, but what happens is the take enough of the recession out to compromise the extra fire ring in the head gasket and new it does sel or doesn seal for long. Anything on 1500block using stock type piston, decking wise, can be no more than very thin clean up cut, .010" at max.

Oh and the news gets even better, there is no special head gasket to correct this.
 
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