Possible to clean carbon deposits without removing head?

[BigD_83]

Forgive the naivety of this question, but is there any way to clean carbon deposits from a cylinder face, without removing the cylinders, and without damaging anything else?

I'd have no issue with doing it the old fashioned way as part of a tear down, but when a bike is running well enough for the moment, would there even be a benefit to cleaning up the cylinder in place? Or would it cause more problems than it would solve?

 

[bwringer]

Carbon deposits are perfectly normal in these engines.

What leads you to believe that the deposits should be removed?

 

[chuck hahn]

have been many talks about getting the bike warmed up and using a squirt bottle to spray water into each cylinder via the carb..kinda like when water hits pan and deglazes the bottom. Ive done it on cars and saw much black water run out the exhaust pipe. Never really have had a need on abike though. You gott rev it pretty high and meter the water in just enough to keep it from stalling.

 

[BigD_83]

Carbon deposits are perfectly normal in these engines.

What leads you to believe that the deposits should be removed?

Pure OCD...

it was a passing thought as I was working on the bike the other day when I gazed into the bore and caught sight of a grimy looking piston coming back up at me.

 

[Nessism]

Leave it alone.

 

[BigD_83]

Chuck,

That sounds similar to some techniques I've heard of for airplane pistons.

It's not often you get a definitive don't mess with it, but it's appreciated Ed.

This, for me, is one of those "ain't broke..." moments. I think it's beyond my pay grade to go further than pose the question.

Thanks.

 

[tkent02]

It can be cleaned using water, but if there is not a problem don't mess with it.
Put a hose connection on the port where you connect to synch the carbs, let a tube suck water into the engine as you ride. Use a valve like the ones for fish bowl pumps to control the flow. A two liter bottle of water into each cylinder should do it. Get the engine warmed up, get going down the road, crack the valve to get a slow trickle. When the bottle is empty move to the next cylinder.

By the time you get the last one clean, the first one will be carboning up again.
The carbon really is normal on pre FI engines, unless you have a detonation problem you can't figure out, it's not worth doing.

 

[1_v8_merc]

The only "clean" pistons I've seen on these bikes, were the ones that have a hole blown threw 'em, from running too lean.

Just leave it alone, it's like a 30 year old protective coating! hehe

 

[Guest]

have been many talks about getting the bike warmed up and using a squirt bottle to spray water into each cylinder via the carb..kinda like when water hits pan and deglazes the bottom. Ive done it on cars and saw much black water run out the exhaust pipe. Never really have had a need on abike though. You gott rev it pretty high and meter the water in just enough to keep it from stalling.

I used to do that with my V6 Johnson/Evinrude outboards, a outboard motor mechanic recommended I do it and told me how. Old two strokes runs so much dirtier though, more of a need to do that.

 

[DannyMotor]

Pour about a teaspoon of Seafoam or Marvles Mystery Oil into each of the cylinders. Leave the plugs out and SLOWLY rotate the motor 3 or 4 revolutions. Let it sit overnight.

Put about 4-5 tablespoons of seafoam or Marlvels Mystery oil into your gas tank (if the tank is about 1/2 full or more).

The next day... put your plugs back in... re-connect everything... and crank it over.

Go ride it around 50 or-so miles... then double check your pistons... I guarantee you they'll be at least 50-70% less 'carbony' than you started with.

Again... soot/carbon is normal... even in a 100% perfectly tuned motor. Your best bet for prevention is to run some sort of carb-cleaner, or seafoam every couple of tanks... and to use the HIGHEST octane gas you can find. Shell normally has Ultra High test... use it.

I don't care what ANYONE says about 89' octane... or 'waste of money'... in small motors (anything under 2.0L that's not being run on the highway every day like a commuter car)... run the highest-octane gas with a good balance of detergent, nitrogen, and ethanol.