Heymow - Lawnmower Racing Forum

Engine Help => Honda and Clone Engines => Topic started by: garretttpe on November 06, 2015, 02:30:21 pm

Title: GX340 smokes
Post by: garretttpe on November 06, 2015, 02:30:21 pm
Hi All
Newbie here with a question. I have a GX340 GC05-3127412. can any one tell me what year it is. I can't seem to find out.
SMOKE QUESTION. This motor was given to a Amish friend of mine and it smokes alot at all speeds continually. I tore it down and the valve stem seals appear to be hard and not soft so I am sure that is problem 1. When I removed the head there was oil sitting on top of the piston, about a half a eye dropper amount. The piston head is clean and not carbined up. The cylinder walls have good cross thatching with very very miner horizontal lines. With the cylinder wall all cleaned I removed the spark plug and turned the engine over with a drill for about a minute to simulate it running and a very very small amount of oil was forming on the cylinder wall.

1. Are my rings bad
2. Do I need to re hone the cylinder wall
3. I assume new valve stem seals
This engine will be used on many different types of equtment they use so I will not be doing any mode. It starts on 2 pulls and runs perfect except for the bad smoking

There was a round spacer under the exhaust valve ontop of the head, but not the intake is this correct?

Plus I would like to know a good place to call and order factory stuff at a fair price. I am in Northern Maine if that Matters

Thanks to all for advice on this
Larry
Title: Re: GX340 smokes
Post by: rotten ron on December 14, 2015, 04:41:42 pm
Seem like it needs rings,when using a high lift cam there is sometimes no room for valve seals and even with no seals they don't smoke
Title: Re: GX340 smokes
Post by: Huffy044 on December 15, 2015, 12:05:27 pm
Might also have been the head gasket, the area between the valves and crankcase, kinda hard to see.

In the future simply take a old spark plug, knock pout the guts, add a air fitting and pressurize the engine, if you hear air from the intake valve or exhaust valve or it comes out the crankcase breather, you have found the problem. In this case if you had done  that AND the head gasket was blown, you would have heard air coming out of the oil fill. You might have assumed it was the rings, ?
Title: Re: GX340 smokes
Post by: berthyd on December 15, 2015, 01:13:27 pm
Nicorette gum helps to stop smoking.

Bert
Title: Re: GX340 smokes
Post by: BIG AL 202 on December 15, 2015, 01:26:37 pm
ONLY IF YOU CHEW IT