rwidman
Lieutenant
- Joined
- May 27, 2004
- Messages
- 1,396
I have a 2003 Glastron GS249 with a Volvo 5.0 carbureted engine with about 150 hours. It's been winterized each season and I've never had a starting problem. A month or so ago I took it for the Volvo 100 hr service. Included were checking timing, ignition,, etc., and replacing the spark plugs. Shortly afterwards, I began having cold start problems. The engine seems to be flooding but won't start. One time I eventually got it started, let it run, turned it off and restarted it without problems. It started fine a few more times and then again refused to start (cold). Since the ramp was halfway to the marina where the work was done I took it there. The mechanic checked for spark, fuel, etc., and then removed the plugs. They were wet with water. He did a compression check (it had been done during the service) and found no problems. He cranked the engine over a few times with the plugs out, dried them and reinstalled them. The engine fired right up.<br /><br />A few days later, same problem, no cold start, plenty of gas in the carburetor. I took the plugs out and again, they were wet with water. Also, they were not the plugs called for in the service manual, they were iridium plugs gapped at .60, not the .35 recommended in the manual. I bought a new set of plugs, gapped them, installed them and the engine fired right up.<br /><br />I've now taken to starting the engine before heading for the ramp. Today, same thing, no cold start and the plugs were wet.<br /><br />The marina owner is suggesting that there is water intrusion through the exhaust because the risers are not high enough. I find this hard to believe because it worked fine for about three years and I've had no problems restarting on the water.<br /><br />He also suspects water in the gas. The gas in the fuel filter shows no signs of water. He suggested adding a few cans of "dry gas" which I did. In retrospect, this was probably not a good idea, I just added more ethanol to the fuel. It's entirely possible that rainwater or water from washing the boat got into the tank through the filler cap. I remember finding it somewhat loose once.<br /><br />Since the compression checks were fine, I cannot think of a way water could be getting to the spark plugs except through the fuel system but I can't see any water. Also, when and if I do get it started, it runs fine and restarts after several hours without difficulty.<br /><br />I'm beginning to suspect a problem related to "phase separation" of the fuel. Web searches on the subject indicate that with enough water in ethanol blended fuel, it will separate into layers and cause starting problems.<br /><br /> http://www.chevron.com/products/prodserv/fuels/bulletin/oxy-nona/concerns.shtml <br /><br />The solution seems to be to discard the fuel and start over with fresh fuel. Pretty hard to do with an inboard tank.<br /><br />Thoughts? Suggestions? Is there a way to test fuel for phase separation?
