Nailhead
Active Member
....thought I'd share my latest shot at something new to me and maybe most of you, so take a look and you'll learn something new in case you ever need it done.
If your engine suffers from blowing head gaskets or has coolant leaks into the cyl then this trick may help you. It called O - Ringing the block.
Very commonly done with high compression engines or ones that are boosted
well beyond the factory specs.
In my case here I have a 81 GMC with the 5.7 olds diesel, which has a
history of blowing head gaskets . Why ? , cause 10 head bolts on a 22.5/1
comp engine just ain't enough. The factory head bolts were not strong
enough either. I had the heads planed , replaced the head bolts with ARP
studs which use a hardened washer and nut and is as good as it gets for
clamping force that won't let go. But the block is just not perfect now and
just after a few thousand miles it starts blowing compression into the water
jacket. The fire ring in the gasket ain't much to stop that kinda pressure
and the jackets are close by so again it fails. To remove the block and
strip it to get refaced is a major job. So I decided to try doing the
O-Ring , I have nothing to lose but my time .
I bought the tool made by Iskendarion , the famous camshaft company. It is fairly simple actually . The tool has a cutter on the side. You install the tool in the cyl bore, adjust it so it rest on the outer edge of the cyl, set the cutter to desired depth and simply turn the unit with the 2 handles evenly untill a grove is cut in the block. Then a copper wire is tapped into the grove partially sticking out and this part will bite into the head gasket when the head is torqued down. Thus a wall is formed and keeps the compression in if the fire ring lets go.
The measuring is very important and must be accurate. Copper or stainless wire can be used. Copper came with the tool so that is what I used, .038 thick. Depending on the head gasket thickness, the ideal height of the wire is .010 - 015" above the deck. So I cut the grove in the block .025" , there is a press fit of about .001 tapping in the wire with a plastic
hammer, thus leaving me .013 above the deck . I took time trying to butt
the ends of the wire a perfect as possible although it is not crucial that
the butt is perfect. Cutting the grove only takes a few minutes. If the
block was sitting on the floor I could cut the 4 cyls easily in 15 minutes.
But in frame with a not so good back it took me alot more time with the
measuring and all making sure I didn't screw up. It turned out pretty good
for my first attempt at this. I can't see it not helping, time will tell. I'm just doing
the one side as this is the one that this .020 bored Goodwrench has failed me
in the past twice now.
I got it together and initial test run shows all to be OK. I did a compression test on just one cyl cold engine and a few cranks on the starter showed 420 lbs. Last winter I never had it plugged in ever, it sits in a cold steel machine shop and it has started at -41 not plugged in. Glow plugs only with good batteries and 0-40 syn oil. Tonight I left it outside not plugged, might hit -30 over night and windy, we'll see if it fires in the morning...
If your engine suffers from blowing head gaskets or has coolant leaks into the cyl then this trick may help you. It called O - Ringing the block.
Very commonly done with high compression engines or ones that are boosted
well beyond the factory specs.
In my case here I have a 81 GMC with the 5.7 olds diesel, which has a
history of blowing head gaskets . Why ? , cause 10 head bolts on a 22.5/1
comp engine just ain't enough. The factory head bolts were not strong
enough either. I had the heads planed , replaced the head bolts with ARP
studs which use a hardened washer and nut and is as good as it gets for
clamping force that won't let go. But the block is just not perfect now and
just after a few thousand miles it starts blowing compression into the water
jacket. The fire ring in the gasket ain't much to stop that kinda pressure
and the jackets are close by so again it fails. To remove the block and
strip it to get refaced is a major job. So I decided to try doing the
O-Ring , I have nothing to lose but my time .
I bought the tool made by Iskendarion , the famous camshaft company. It is fairly simple actually . The tool has a cutter on the side. You install the tool in the cyl bore, adjust it so it rest on the outer edge of the cyl, set the cutter to desired depth and simply turn the unit with the 2 handles evenly untill a grove is cut in the block. Then a copper wire is tapped into the grove partially sticking out and this part will bite into the head gasket when the head is torqued down. Thus a wall is formed and keeps the compression in if the fire ring lets go.
The measuring is very important and must be accurate. Copper or stainless wire can be used. Copper came with the tool so that is what I used, .038 thick. Depending on the head gasket thickness, the ideal height of the wire is .010 - 015" above the deck. So I cut the grove in the block .025" , there is a press fit of about .001 tapping in the wire with a plastic
hammer, thus leaving me .013 above the deck . I took time trying to butt
the ends of the wire a perfect as possible although it is not crucial that
the butt is perfect. Cutting the grove only takes a few minutes. If the
block was sitting on the floor I could cut the 4 cyls easily in 15 minutes.
But in frame with a not so good back it took me alot more time with the
measuring and all making sure I didn't screw up. It turned out pretty good
for my first attempt at this. I can't see it not helping, time will tell. I'm just doing
the one side as this is the one that this .020 bored Goodwrench has failed me
in the past twice now.
I got it together and initial test run shows all to be OK. I did a compression test on just one cyl cold engine and a few cranks on the starter showed 420 lbs. Last winter I never had it plugged in ever, it sits in a cold steel machine shop and it has started at -41 not plugged in. Glow plugs only with good batteries and 0-40 syn oil. Tonight I left it outside not plugged, might hit -30 over night and windy, we'll see if it fires in the morning...
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