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Discussion Starter · #1 ·
I recently bought a 1987 Honda 350 with low compression I’m hoping it’s just a stuck valve and not piston and rings
It currently doesn’t start has good spark and gas does anyone know the symptoms of a stuck or bent valve?
Tia
 

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Download the service manual from the link in my signature block below

to check the valves you will have to remove the breather box as explained in the manual.

mine had a bent valve also—You can tell when you rotate the engine that the valve doesn’t move. i had the Honda shop tech replace it after I stripped it down to the valve cover
151707
 

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Discussion Starter · #4 ·
Download the service manual from the link in my signature block below

to check the valves you will have to remove the breather box as explained in the manual.

mine had a bent valve also—You can tell when you rotate the engine that the valve doesn’t move. i had the Honda shop tech replace it after I stripped it down to the valve cover
View attachment 151707
Ok when yours had a bent valve did it turn over like it had no compression?
 

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The guy I bought it from told me he thot it had a bad valve—i didn’t have a compression tester all i knew it that it cranked but didn’t fire. I bought a hard copy service manual off fleabay—good money there!

spray all your screws and bolts with penetrating oil about once a day for a week before trying to break the bolts loose. Especially the valve cover bolts—they strip and break super easy. Use the best six point sockets you can find on bolt heads. I use a non-ratcheting breaker bar (i bought 1/4” and 3/8” breaker bars especially for loosening the valve cover bolts. I used very gradual torque—i never broke one bolt.
 

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Discussion Starter · #6 ·
The guy I bought it from told me he thot it had a bad valve—i didn’t have a compression tester all i knew it that it cranked but didn’t fire. I bought a hard copy service manual off fleabay—good money there!

spray all your screws and bolts with penetrating oil about once a day for a week before trying to break the bolts loose. Especially the valve cover bolts—they strip and break super easy. Use the best six point sockets you can find on bolt heads. I use a non-ratcheting breaker bar (i bought 1/4” and 3/8” breaker bars especially for loosening the valve cover bolts. I used very gradual torque—i never broke one bolt.
That’s good information to know thanks!
 
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