kohler ch25 (AND OTHERS) BREATHER REED

[cashman]

If someone has the tools available, do a leakdown test on it before you do anything. That will get you pointed in the right direction real fast.

 

[MBDiagMan]

I just remembered something from the past. It probably won't apply to your engine, but maybe it will make you think of something similar.

I was working on an old Tecumseh OHV engine that was smoking. The problem turned out to be a breather in the top of the rocker cover that was in backwards allowing the oil to came up the pushrod tube to blow out the breather pipe. If the engine was doing this when you purchased it, make sure nothing is put on backwards.

Larry

 

[tmar04]

I just remembered something from the past. It probably won't apply to your engine, but maybe it will make you think of something similar.

I was working on an old Tecumseh OHV engine that was smoking. The problem turned out to be a breather in the top of the rocker cover that was in backwards allowing the oil to came up the pushrod tube to blow out the breather pipe. If the engine was doing this when you purchased it, make sure nothing is put on backwards.

Larry

Thanks, Larry . It was s moking and using oil. Seller ( neighbor) told me prob would need rebuilding. Only thing I can think of is reed valve , other than rings, When I remove air cleaner base, disconnect hose from breather tube and start and start engine , pressure is obvious . No vacuum . I will check compression today.

 

[MBDiagMan]

With that further information, I would suggest that you buy or borrow either a cylinder leak down appartus or a spark plug hole/air hose adapter. Pressurize the bad cylinder after firmly blocking crankshaft movement while piston is at top on the compression stroke. Pressurize the cylinder and listen for where the air is escaping. If you hear it through the exhast pipe, an exhaust valve is leaking. Through the carburetor and an intake valve is leaking. Through the oil fill hole and it is leaking past the rings indicating that you have cylinder/ring/piston issues.

If it DOES turn out to be damage in only one cylinder, there is absolutely nothing wrong with repairing that one cylinder only. If the engine is just generally worn out, then you will, of course want to overhaul both cylinders.

These engines are new enough, that I expect pistons/rings and any other engine parts to be readily available. When I've rebuilt small engines in the past, it always seems to be ones that are old with difficult parts availability.

Hope this helps,
Larry

 

[tmar04]

With that further information, I would suggest that you buy or borrow either a cylinder leak down appartus or a spark plug hole/air hose adapter. Pressurize the bad cylinder after firmly blocking crankshaft movement while piston is at top on the compression stroke. Pressurize the cylinder and listen for where the air is escaping. If you hear it through the exhast pipe, an exhaust valve is leaking. Through the carburetor and an intake valve is leaking. Through the oil fill hole and it is leaking past the rings indicating that you have cylinder/ring/piston issues.

If it DOES turn out to be damage in only one cylinder, there is absolutely nothing wrong with repairing that one cylinder only. If the engine is just generally worn out, then you will, of course want to overhaul both cylinders.

These engines are new enough, that I expect pistons/rings and any other engine parts to be readily available. When I've rebuilt small engines in the past, it always seems to be ones that are old with difficult parts availability.

Hope this helps,
Larry

Larry, Checked compression after mowing 1 hour. Bad cyl 100 lb, good cyl 130. Good plug burning clean, bad one has oily deposits . Think I will plan on rings and valve lapping this winter . Thanks for your help (
, as well as others). Great forum! Terry

 

[Fish]

Larry, Checked compression after mowing 1 hour. Bad cyl 100 lb, good cyl 130. Good plug burning clean, bad one has oily deposits . Think I will plan on rings and valve lapping this winter . Thanks for your help (
, as well as others). Great forum! Terry

So no reed valve?????