1939 H

[thessler]

Hi
i have posted recently about my H not having compression.
I believe I have finally figured it out. When I cleaned up the cylinders , the hone left slight egg shape where the rust spots were. So the compression is getting around the rings in those spots. So now what to do ?
Apparently the original bore should be 3.562. If I get a clean up cut with a boring bar or a ridged hone, how large can I go and still use the old pistons. I have already put new rings on them.
otherwise what are my options ?
Thanks,Tom

 

[Loosehandle]

Hi
i have posted recently about my H not having compression.
I believe I have finally figured it out. When I cleaned up the cylinders , the hone left slight egg shape where the rust spots were. So the compression is getting around the rings in those spots. So now what to do ?
Apparently the original bore should be 3.562. If I get a clean up cut with a boring bar or a ridged hone, how large can I go and still use the old pistons. I have already put new rings on them.
otherwise what are my options ?
Thanks,Tom

You will need oversized pistons or sleeves and use your current pistons.
My H block was cracked around center stud so Id have that checked also.

 

[Mike(NEOhio)]

How egg-shaped are the bores? Seems to me that alone would not make for zero compression. A ridged hone can make them round again but oversize rings will not seat well if the pistons are too loose in the bores. It will run but won't last long.