Cleaning Combustion Chamber per B&S

[seattlepioneer]

12f8022021e1

I notice that the Briggs operating manual specifies that the "combustion chamber" m should be cleaned every 100-300 hours of operation.

I'm supposing that would involve opening the head and inspecting and cleaning the head of the piston and valves as needed ---or something else?

What kinds of things might you expect to find on a new or old mower when doing this as ordinary maintenance? Is that something often neglected?

I've seen a You Tube video of an engine with no compression due to a cylinder scored with crusted oil deposits. The mower was junk due to the damage. Perhaps that would have been avoided if that kind of routine maintenance has caught the oil accumulation earlier?

 

[Fish]

Usually neglected, generally not harmful. Even raises the compression ratio.
If it is hard jagged carbon, it usually indicates oil/blowby carbon, and the rings are shot.
Normal will be a dark powdery buildup, that can be easily removed.

 

[seattlepioneer]

Usually neglected, generally not harmful. Even raises the compression ratio.
If it is hard jagged carbon, it usually indicates oil/blowby carbon, and the rings are shot.
Normal will be a dark powdery buildup, that can be easily removed.

Thanks for your comments.

I have an old mower that has probably never had this kind of service done:
99062966/12F8022021E1. It works fine.

I have never had occasion to open up the head on an engine, and I'm imagining this would be an opportunity to learn those skills and see the condition of the combustion chamber, valves and such on an old piece of equipment.

 

[bertsmobile1]

Back in the day of low compression engines & 65 octane petrol, decarbs were part of routine maintenance.
The easy way was to pull the muffler off , start the engine then spray water down the carb .
Still do the pre WII motorcycles that way.

 

[tom3]

I suppose to some extent the carbon buildup insulates the head and reduces heat transfer out of the upper block. Wouldn't hurt to clean that off now and then and get a bit better cooling. Along with a good cleaning of the cooling fins around the cylinder.