Loss of compression
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Re: Loss of compression
Even if it's a monotorque, re-torquing won't do any damage.
Regarding oiling the bolts threads, there's tons of conflicting info about it. I saved a link in this regard, but's at my work computer (give's you an idea of the time I devote to it). Will post tomorrow. From what I recall I think it is no oil.
Don't go into the theory behind, because it's really complicated. I don't think the service manual states this...
Regarding oiling the bolts threads, there's tons of conflicting info about it. I saved a link in this regard, but's at my work computer (give's you an idea of the time I devote to it). Will post tomorrow. From what I recall I think it is no oil.
Don't go into the theory behind, because it's really complicated. I don't think the service manual states this...
Owner of the same Patrol since 1967
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Re: Loss of compression
Well i put the head gasket on with no joy, I did oil the head bolts but that shouldn't have made to much difference. I guess its a rebuild.
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Re: Loss of compression
Well, that blows. 
That will keep you down for a little while, but worth it in the end. 
That will keep you down for a little while, but worth it in the end. Beyond any hope for intervention
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Re: Loss of compression
Remdogg, don't get discouraged yet.
If the head is ok, then the two other items that can be at fault will be the piston rings, and the valves.
There's a test using an adapter for the spark plug hole and connecting it to an air compressor.
1. You bring the piston at the cylinder that you want to examine to the top, making sure it's in the compression cycle.
2. Connect the adapter to the air compressor. Note: at this point you need the help of another person that can press the brakes and prevent the engine from trying to rotate under the compression. As you see the car has to be in gear, preferable 3rd.
3. Pay attention at where you hear a hissing noise, produced by the air escaping.
a. You hear through the carburetor, intake valves at fault.
b. You hear through the exhaust, exhaust valves at fault
c. You hear through the oil cap, piston rings.
I guess that the air pressure for this test can be set at 50psi to begin. Will be enough to detect the above.
You told us that the cylinders looked ok, so that's a good start. All the above can be corrected with the engine in place.
Fixing the valves will require that you remove the head again, and do a complete valve job at this point.
The pistons can be easily removed once you take the oil pan. You'll need a ridge reamer to take out what little ridge has formed at the top of the cylinder walls, to prevent scratching the pistons and/or braking the piston rings in the process.
Fit new piston rings, new gaskets.
And
Then, 
If the head is ok, then the two other items that can be at fault will be the piston rings, and the valves.
There's a test using an adapter for the spark plug hole and connecting it to an air compressor.
1. You bring the piston at the cylinder that you want to examine to the top, making sure it's in the compression cycle.
2. Connect the adapter to the air compressor. Note: at this point you need the help of another person that can press the brakes and prevent the engine from trying to rotate under the compression. As you see the car has to be in gear, preferable 3rd.
3. Pay attention at where you hear a hissing noise, produced by the air escaping.
a. You hear through the carburetor, intake valves at fault.
b. You hear through the exhaust, exhaust valves at fault
c. You hear through the oil cap, piston rings.
I guess that the air pressure for this test can be set at 50psi to begin. Will be enough to detect the above.
You told us that the cylinders looked ok, so that's a good start. All the above can be corrected with the engine in place.
Fixing the valves will require that you remove the head again, and do a complete valve job at this point.
The pistons can be easily removed once you take the oil pan. You'll need a ridge reamer to take out what little ridge has formed at the top of the cylinder walls, to prevent scratching the pistons and/or braking the piston rings in the process.
Fit new piston rings, new gaskets.
And
Then, Owner of the same Patrol since 1967
