Robin-Subaru lots of carbon in cylinder

[moped-dan]

Im doing mantenince on the Robin-Sebaru EHO35 to get her ready for spring. I replaced the spark plug and it looked a little dark but normal. I looked into the cylinder and on the top of the piston it is all black and covered in carbon, is this normal? What could cause this and can I clean it off?

 

[give me vtec]

that is always normal on an internal combustion engine.... were you expecting a mirror finish??

 

[GearNut]

Add some SeaFoam to yer gas. Follow the instructions on the bottle. That'll clean it out while you ride, and get every nook and cranny sparkling.

 

[BigDaddyT]

LOL Seafoam is status quo up here. I thought it was just a local thing. Fer the old subaru cars they use Restore too. Seafoam is like a tuneup and Restore is for cars with bad rings and such.

 

[Mountainman]

pay no attention

noticed some carbon
on top
but it still does
sing
pay no attention
just
ride that THING

MM​

 

[HoughMade]

noticed some carbon
on top
but it still does
sing
pay no attention
just
ride that THING

MM​

Burma Shave​

 

[GearNut]

"Burma Shave"
ROTFLMAO!!!!!!!!!!

 

[Member 5549]

Moped-Dan It's seems your robin has a carbon footprint !!!!!
I could't resist !!!
The best thing you can do for these engines is run the heck out of them !!!!
the more you use them the longer they last !!!
well sorta ??

 

[Silvaire]

Dan,

What you describe may be normal.

On the other hand, it may not be...

There are two things I would check - the air cleaner condition and the oil level.

First, check the air cleaner. Check that both the foam and paper elements are dry and clean. (The EH035 does not use an oiled foam element.) A dirty air filter will cause an engine to run too rich, causing soot to form on the piston and combustion chamber. An overly rich mixture will also wash the the oil film off of the cylinder walls, which causes wear leading to oil burning.

Second, make sure you have the proper amount of oil in the engine. Either too much or too little oil will cause problems. Too much oil in the crankcase will cause the engine to blow oil out the breather tube and into the intake, causing carbon build up.

 

[moped-dan]

Thanks for all the advice... MM i love the poem.

Silvaire I have the right amount of oil and the air cleaners are dry so I think ill let it be. The engine is running great I was just worried to much carbon would cause a problem.