lb 10655 has no compression

14 years ago

Hello all, I have a 3 year old lawnboy #10655 gold series lawnmower. Yesterday my daughter was cutting the grass, the mower popped and died. she could not get restarted. I came home and checked the spark. At first i could not see any spark on the plug. Eventually i saw spark at the plug. I put my finger tip in the plug hole and had my brother pull the cord. No compression. The piston goes up and down. the valves are going up and down. I put the spark plug back in and gave it a shot of starting fluid and it won't fire. Does anyone have any ideas as to the problem or what to look at? thanks all.

Sort by:Oldest

Comments (6)

tomplum
14 years ago
Perchance did the valve cover get hit and dented? My first step would be to sneak the cover off and take a look up top anyways.
aliasmax
Original Author
14 years ago
I did remove the valve cover and everything was normal. nothing broken and valves moving up and down. thanks for the reply
Related Discussions
Help with identifying coil for 10301 LB
Q
Comments (5)
It's possible that you have lost the 'start' mode in the CD ignition that is set for 800 RPM and less. As long as the replacement CD unit fits the mounting holes and is for a L:awn-Boy you should be okay. Set it up with a business card between the unit and the flywheel then remove the card after tightening. Should be about right. There are some things to watch for on the 'V' engine. They used 'Tri-Round' thread-forming bolts in critical areas, and you need to check all fasteners on the engine at least three times during the cutting season; before, during and after. This includes the tank and air shrouds, the mounting bolts, the muffler cover bolts and the muffler plate bolts under the muffler cover. The stamped-steel muffler cover wears out pretty fast and should be replaced if it rusts out or won't seal.
...See More
10324 LB Re-Jet Question
Q
Comments (21)
Since it acts the same under load, I think you're right---there's another issue. Surging due to lean jetting doesn't cause the engine to stall eventually. According to the Toro E Engine Service Manual (available as a free download on Lawn-Boy's website), possible causes for surging are: 1. Fouled idle circuit (Remedy is to clean it) 2. Air leak (Remedy is to check sealing surfaces, oil seals, & gaskets) 3. Restricted fuel flow (Remedy is to check filters and fuel line) 4. Engine RPM too low (Remedy is to increase governor spring tension slightly) 5. Air vane sticking (Remedy is to clean or replace) You've cleaned the fuel tank, cleaned the carburetor, and replaced the carburetor gaskets. That leaves cleaning the idle circuit, checking the crankcase seal, the head gasket, and the oil seals, and cleaning the air vane. Hope this helps.
...See More
LB S21ZST not running - close
Q
Comments (3)
Thanks mucho, good places to start, the muffler will be no problem to clean, any suggestions on how to check the reed valves?
...See More
compression
Q
Comments (49)
"what sould the com be on a 5hp b&s engine. i put a new head gasket on it,im getting 30 psi. wasgetting 0 before, the valves seem to be working but i cant start this leaf blower for nothing, im getting gas & spark. How long should it hols the 30 lbs." Let's circle back to what the original poster was asking about and re-read what he said. He was getting -0- before and 30 psi after a head gasket change. To me that indicates the possibility of a warped head - or a poorly installed new head gasket.
...See More
1saxman
14 years ago
'The piston goes up and down. the valves are going up and down'

Those are the main factors and rule out most major problems. This engine may have compression release for easy starting. I'm not sure how it works on the Honda, but maybe it's stuck.
tomplum
14 years ago
"I did remove the valve cover and everything was normal. nothing broken and valves moving up and down." What we are looking for is are the the valves actually closing. Excessive looseness in the rocker would be an indication of a loose valve seat or more likely debris between the valve and seat. This is provided there isn't an adjuster problem. No clearance at the rocker won't allow the valve to shut either. I've seen these valves stick, so make sure they are moving freely. That is normally due to old fuel deposits on valves after the engine has been sitting for a while however. Popping sound is peculiar. ..
aliasmax
Original Author
14 years ago
I found the problem. My daughter must of hit the swing with the valve cover. It was dented in just enough to not let a valve close. Pounded out the valve cover, reinstalled it and it fired right up. Thank you for the replies.
1saxman
14 years ago
You can order a cast aluminum cover that comes on the GSV 190 commercial engine and it's a direct swap. Even with the cast aluminum cover, the Lawn-Boy commercial mower has a steel rod brush guard in front of the engine.

Here is a link that might be useful: {{gwi:141485}}

lb 10655 has no compression

Comments (6)

tomplum

aliasmax
Original Author

Related Discussions

1saxman

tomplum

aliasmax
Original Author

1saxman

COMPANY

BUSINESS SERVICES

GET HELP

CONNECT WITH US

lb 10655 has no compression

Comments (6)

tomplum

aliasmaxOriginal Author

Related Discussions

1saxman

tomplum

aliasmaxOriginal Author

1saxman

COMPANY

BUSINESS SERVICES

GET HELP

CONNECT WITH US

aliasmax
Original Author

aliasmax
Original Author