Hobbyist Forums banner

1 - 7 of 7 Posts

·
Registered
Joined
·
3 Posts
Discussion Starter #1
Mowin' the lawn... life's beautiful... sucker just quit. Has fuel in the float bowl. Has spark. But wait... ZERO compression? I removed the valve cover, valves open and close about where they should in relation to the piston coming up and down (near as I can tell shining a flashlight in the plug hole). I did try forcing air down the plug hole( at low psi ) with piston at TDC ( both ) and I think air is passing thru the intake valve.

I thought Hondas were bullet proof?
Anyone have similar failures?
What do I do next ( I already opened a beer)?
Words of wisdom and hostile taunts welcome.
 

·
Registered
Joined
·
6,116 Posts
Check the valve clearance on the valves with the engine on Top Dead Center on the compression stroke. If intake valve is leaking, it's probably sticking, this will be verified by excessive clearance on the intake valve. Old gas is a common reason for the valves to stick. If this is the issue, spraying some carburetor cleaner through the carburetor and on the valve stem, may cure your issue.

While Honda engines are good, they are far from bullet proof. The break down, as frequently as most any quality engine.
 

·
Registered
Joined
·
3 Posts
Discussion Starter #3
Thanks 30YT. While I was waiting the 5 long minutes for you to reply, I read some of the other threads on the subject. You are the GURU, man.

I thought I was using fresh fuel, but here in oregon we get 10% ethanol year round. It really does wonders to the fuel economy of my slant 6. I'll let you know how I make out.

Thanks again for the quick reply!
 

·
Registered
Joined
·
3 Posts
Discussion Starter #4
I'm reading 12 or 13 thousandths on the valves, but when I manually push on the rocker arms, the exhaust valve slams shut with this nice metallic "slap", while the intake kinda comes to earth with a dull pathetic "thud" sound.

Anything besides carb cleaner I can try before breaking out the scalpel?
 

·
Registered
Joined
·
11 Posts
What a coincident!!! Recently had help from 30yeartech on my Honda GXV140 engine. Thought it was head gasket but ended up being intake valve seat. Took it to a small engine repair shop and they cut the seat as part of a valve job. $37 dollars later, started on first pull...you can try to lap the valves by hand but worth the money to have a shop take care of that issue...good luck...
 

·
Registered
Joined
·
6,116 Posts
You can also use brake cleaner, just about anything that will dissolve any build up on the valve stem. Some penetrating oils will work or Sea Foam deep creep. It sounds from your description that both valves are sticking. If you have to take the valves out, you will have to split the crankcase on a GCV series engine, the head does not come off.
 
1 - 7 of 7 Posts
Top