by Oldfrog » Tue Apr 06, 2010 3:27 am
Hi. Sorry you're having troubles. I'm NO pro marine tech, but I've been around 2 strokes all my life. ( family used to own a Yamaha bike dealership) and I've rebuilt more than a couple of OMC engines.
So take my advice for what it's worth... :)
Here is how I'd approach your problem, based on what you posted:
1. I'd do a compression check on it. Go to autozone and buy a cheap gauge. You want both cylinders to be nearly equal...and over 90 lbs...as I recall. But dont quote me on that number. If one is more than a few lbs ( 5-8) lower than the other, there is one of your problems.
2. I'd check the fuel line and all connections carefully....especially if you've been running ethanol laced fuel. It eats away at the older lines from the inside and generally mucks everything up. Nevertheless, the fuel line and bulb will need to eventually be replaced with the "ethanol rated" type.
3. Check the fuel filter. My guess is that you'll find some gunk...which tells you the fuel line is toast and that your carb needs a rebuild. ( probably needs that anyway)
4. Make sure both plugs are firing by starting at home with the ear muffs hooked to your waterhose and use an inductive timing light on each plug wire. You could have a coil breaking down.
5. Not related to your current issue....but change the waterpump after you get her running right again. Waterpumps are cheap. Powerhead rebuilds are not. I swap mine every year.
Like I said earlier... I'm no pro by any means. But without hearing it run, inspecting the plugs myself, etc....these items are what came to me first.
Hope it helps !
P.S. I try to always run a little Seafoam AND Marine Stabil ( green/blue type) in my tank at all times. I havent had to rebuild my carbs in 10 years...and no...I dont run the gas out of them at the ramp. That only causes a lean condition which can fry rings. ( not the kind you eat with ketchup, either !)