Rebuild/Compression Check

[AnvilheadTX]

When one is rebuilding an 8n engine (in this case a 6v front mount) - at what point can a comppression check be done to ensure that there is no more blow-by. My project tractor is calling my name and it has low compression in #1 and blow-by (when it last ran). I want to fix that problem - hopefully new rings. However, before putting it back together I want to check the compression when the block work is complete. I am guessing all is needed is the battery, wiring harness (less spark plug wires), starter and generator? Am I right?

 

[Brian Bell]

You *could* test compression without the generator, and wiring harness. If you do an in-frame overhaul, you can test compression after the head is back on. If you are going as far into the engine as you are, I would consider putting sleeves in it too, to be sure you fix the blow-by.

 

[Hobo,NC]

the compression numbers are cylinder leakage would be inconclusive till the engine has run for a few hours to seat the rings. One could tell if he had valve leakage tho.
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[AnvilheadTX]

What is an "in-frame" rebuilt? Would you suggest rings, sleeves and valves?

 

[Brian Bell]

I would consider an in-frame replacing sleeves, rings, rod bearings, possibly mains, etc. Whatever can be done without splitting the tractor. If you have good oil pressure and no rod rattle, you might be able to get away with this. I put sleeves, rings, pistons and rod bearings in my '51 8N a while back with everything still attached to the tractor.