Head gasket bore diameter?
#1
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I've fitted the head gasket on the head, but the sealing ring on the gasket is significantly larger than the bore at the top of the block. this doesn't look right to me.
Bore at taper on top of block: 3.939"
Gasket bore................................4.020"
------------------------------------------------
Flange gap.................................0.081"
it almost looks like the gap is there to accomodate overbored blocks. I don't have one of the old gaskets handy, but I've inspected the top flange of the block, and can't see any combustion residue that would indicate that th old gasket was so much larger than the bore. Gasket set is from Victor.
I'm stopping until I get this sorted out. I don't want any leaks.
Bore at taper on top of block: 3.939"
Gasket bore................................4.020"
------------------------------------------------
Flange gap.................................0.081"
it almost looks like the gap is there to accomodate overbored blocks. I don't have one of the old gaskets handy, but I've inspected the top flange of the block, and can't see any combustion residue that would indicate that th old gasket was so much larger than the bore. Gasket set is from Victor.
I'm stopping until I get this sorted out. I don't want any leaks.
Last edited by docmirror; 04-19-2008 at 01:42 PM.
#2
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yes, there should be about 1-2mm gap between the edge of the cylinderwall and the gasket fire ring.
Scots cylinderwall thickness after being bored from 4.7 to 5 liter was near 5mm. this means the effective sealing with the 5 liter head gasket was only about 3mm.
Normal wall thickness is about 7 to 8mm.
mk
Scots cylinderwall thickness after being bored from 4.7 to 5 liter was near 5mm. this means the effective sealing with the 5 liter head gasket was only about 3mm.
Normal wall thickness is about 7 to 8mm.
mk
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Looks like I'm good then. I'll bolt it down and move on. I got the lifters in, lower timing gears and bearings on, I'll torque the heads and have the cams in tonight. Need those tension pads first though. I'll get those tonite at the Ed do. Thanks Mark.
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why do you need the tension pads first. doesnt that go on last? I think my brain is making me forget that tramatic cam replacement process ![Smilie](https://rennlist.com/forums/images/smilies/smile.gif)
mk
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mk
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Put in the light weight lifters Doc, good for 1/2 a horse power.
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