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225 honda no compression

Q

quahog

New member
I just rebuilt the motor and when I started it, it only had 4 cylinders. I pulled the #1 and #5 plug wires off and it made no difference, so I changed the coils and plugs - no difference. A compression test showed 0 for these 2 cylinders. Have checked the timing, is right on. Took the valve covers off, handcranked the motor, and all the valves seem to be opening and closing correctly. Any suggestions? What am I missing?
 
What did you rebuild? My first instinct would be to suspect the head gasket - either the wrong one or incorrectly installed.
 
i did a little epoxy work on block. Bought genuine honda head gaskets torqued to factory specks. work also done on bottom 2 cylinders and these cylinders seem fine.
 
I did pump air into the cylinders...#1 cylinder - no air came out with the timing belt on the #1 mark. But on #5 mark for the fifth cylinder, air came out of the exhaust valve. I was told this probably indicates a stuck exhaust valve. When I handcranked the motor around to the different marks, the valves seemed to be working.
 
Okay - I doubt a valve is sticking open. Back to square one - Test and reset valve clearance on all valves and reset timing belt. You've got something out of sync. I would not attempt to run the engine until you have the correct compression in each cylinder, otherwise you will surely burn a valve.
 
i recheched the timing w/ a friend looking over my shoulder all marks line up. he said timeing mite be off its not. even took off fly wheel to see mark w/ keyway .except for takeing heads off im back to were i started.
 
Well, if all that is correct, then I'm at a loss. Hopefully Mike or Jimmy will jump into this for other suggestions. What part of the block did you epoxy?
 
I expoxied along the water jacket where the bottom meets the heads, both sides. I pulled the heads off and apparently had a stuck exhaust valve in #5. #1 looks fine, still can't figure out what's happening there. I am now putting different heads on from my parts motor. The head gasket was installed correctly, to answer your first suggestion. I'm cleaning the other heads now, I'll let you know what happens.
 
Is it possible that the epoxy job changed the plane of the head - not allowing the head gasket to torque down evenly?

Inspect the removed head carefully - you may have a crack in it, although I've not heard of that happening with a 225.
 
I took heads off parts motor and put those on, started motor yesterday and seems to run fine. Will take out for test ride today...keeping my fingers crossed.
Thank you for all your suggestions, it really helped to get some feedback as I was really lost. Will let you know if test ride works out.
 
The heads must have set for too long and there might have been rust on the valve stems, which stuck. I ended up with a couple of bent valves.
Ran the motor today at work for 2-3 hours and worked well. Thanks, everyone, for your suggestions.
 
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