gas sheen on water

terraplane · Posted: Sat Dec 29, 2007 7:44 pm Post subject: gas sheen on water

I keep the boat in its slip all winter....usually motor up unless severe freeze,...Chesapeake temps around now are highs in 40's and lows in 30's..water temp about 38 degrees. For about a two week period i have noticed that when I lower the engine and start it i get a gas sheen on the water...it stops in about three or four minutes..not severe, but it was not there "before"....Any ideas?

MikeMac · Posted: Sat Dec 29, 2007 8:12 pm Post subject: Gas Sheen

Oh, I can think of a few things, but a few more details might help. Does your engine have carbs or fuel injection? Does the sheen start before you start the engine, or after it's running? I had a similar problem with my Honda BF8 kicker and it was a sticky float valve in the float bowl that wouldn't seat and let gas run out the overflow tube. I noticed it when I was pumping up the gas line. I had to take the bowl off and clean the valve with carb cleaner. Hope that helps!

Mike

terraplane · Posted: Sun Dec 30, 2007 8:53 am Post subject: gas on water

The engine is a carbureted Honda 90, 2005.
The gas sheen happens when i lower the engine. It stops when the engine is running.
Gas tanks are full, lots of Stabil, fresh gas always.
Thanks for any advice

terraplane · Posted: Sun Dec 30, 2007 9:36 am Post subject: gas on water

One more thing: I put in some carburetor cleaner at last gas fill. Would that make any difference?

smittypaddler · Posted: Sun Dec 30, 2007 11:11 am Post subject:

Are you sure it's not oil? Na Waqa had pits on one side of her oil drain plug washer, and because the washer got turned over during an oil change, it started leaking; not much,but enough so you could see a film on the water. Turned the drain plug washer back over so the smooth side was in,and problem solved.

Sea Wolf · Posted: Sun Dec 30, 2007 11:26 am Post subject:

terraplane-

I think MikeMac is on the simplest, most longical track to explain your observation.

One carburetor float is probably sticking or not closing fully and when the motor is tilted up it's passing a small amount of fuel out the carburetor vent.

The cold temperatures could also be adding to this affect by shrinking the metal parts of the valve seat, enlarging the clearances.

Also, the recently added carburetor cleaner may have removed some varnish on the needle valve that helped hide some valve wear at the seat by making a better seal than the metal alone.

Your Honda 90 has four carburetors on it, right?

It's so small and since it quits after a few minutes, probably not worth worrying about, just keep an eye on it.

However, when checking the leak, don't be doing the Groucho Marx routine with the lighted cigar, or you may find the "magic word" to be "Fire!". Xmas LOL

Joe.