Posted by Joe Lorenzino [108.162.241.103] on Wednesday, June 13, 2018 at 21:53:51 :
Is a 1956 270 Poly truck motor an “interference” engine?
If one of the valves is stuck at full open, will it still turn over, or will the piston hit the valve????
Dragged home a 56 Fargo H series truck with a 270 poly V8 in it. Last ran in 1990. Tried turning it over with a socket on the crank bolt, but no luck, so it is “stuck”. Pulled the plugs, and found 2 with light rust flakes on them. Looked down each hole with a bore scope, and saw light “condensation” rust Snow-flakes in those 2 holes, but others look OK, with no obvious water inside any. Mixed up some Acetone & ATF and filled each cylinder up with it. Let it sit for a week then jacked one back wheel off the trailer, put it in 5th gear, and started rocking the duals back and forth. Have got it to move, but can only turn the tires back & forth ¼ turn. Would seem that the engine is Almost making a full rotation, but not quite. I am thinking valves/valves stuck open, just haven’t had time to pop the covers off yet to check. Hoping somebody here knows if they had clearance to rotate at full lift before I wreck anything.
Thanks
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