GX 160/200 Carbon Build-up

Graeme · Joined: 02 Nov 2001 Posts: 17

I have several of these engines but am having a problem with one (a pretty newish one) that creates a lot of carbon. It can be seen on the head, on the plug and in the exhaust while some only produced the "tanned" plug with no buildup on the exhaust, and in complete contrast a few plug is coming out without a mark on it on one other.

I'm just looking for ideas for the one with a lot of carbon. What should I start looking at that might be the cause of such a problem.
Also, is it right for the plug to come out VERY clean?

mac · Joined: 27 Jul 2001 Posts: 50

What might you be using for Oil in these engines?

Steve Nieto · Posted: Mon Apr 08, 2002 8:16 pm Post subject: GX 160/200 Carbon Build-up

AT OUR RECENT CLUB RACE THERE WHERE 2 DQ'S DUE TO CARBON BUILD UP ON THE TOP OF THE PISTON, WHICH CREATED A ILLEAGAL POP UP READING ON THE PISTON . I WAS NOT ONE OF THEM. IN MY OPINION THE CARBON BUILD UP WAS DUE TO OIL. AFTER INSPECTING BOTH OF MY MOTORS WHICH HAD 3 RACES ON THEM, THERE WAS ALMOST NO BUILD UP. A GOOD QUALITY SYNTHETIC SUCH AS POWER PLUS LIGHT SHOULD ELIMINATE YOUR PROBLEM.

Rodney Ebersole · Posted: Wed Apr 10, 2002 5:32 am Post subject: GX 160/200 Carbon Build-up

If the rings or cylinder clearance is large that would also be a contributor to carbon build up along with too big of jet or bad valve seal or bad guides. Do a leak-down test to see the condition of the rings and valve seal. Even a leaky head gasket could contribute to the problem.