Durango318
Seaman
- Joined
- Jun 12, 2010
- Messages
- 68
Well, it's that time again. Will it run?
A friend was having problems with the I/O engine in his Gibson houseboat. It would not idle and was hard to start. It would only somewhat idle if you hold your hand over the carb to pull more fuel. He was tempted to take it out and "blow it out" at high throttle. I didn't think that was a good idea and wanted to check a few things first. The fuel water separator was changed and I noted the fuel smelled like rank turpentine. Bingo! We checked the tank with a dipstick coated with a film of "Kolor Kut water finding paste" (modified formula!) There was a layer of ethanol at the bottom. ONLY the paste of the modified formula turns yellow in the layer of ethanol in the fuel in a few seconds. As it turns out the fuel had phased separated and the tank had to be pumped dry and lines flushed. If we had taken the boat out and ran it hard, there's a good chance the engine would have blown because ethanol runs hotter and leaner in a engine jetted for gasoline. It should be noted that he had been working on trying to get it to run so long that the water/ethanol saturated fuel had washed past the rings and turned the engine oil milky so that had to be changed. The oil stayed clear after hours of run time that confirming this.
With fresh fuel the engine ran great for about 6 hours but then it started running bad (different than before)and finally wouldn't even idle. It was acting like it was starving for fuel or vapor locked. The fuel water separator was poured out into a clear container and visually there were two different layers, about half & half. We checked both the filter's fluid and the tank with the paste and only what was in the filter had phased. Not buying that this is the soul problem I asked the owner to inspect the anti siphon valve. For some (lucky) reason he also removed the 90* elbow that goes into the pickup tube. That's when I got my biggest surprise. There was a small screen in the elbow that was packed with a 3/4" long wad of felt-like trash! A mirror was used to look into the pickup tube for more debris and it was clear. I've not seen this before but the screen was there to protect the valve, however it had so little area it's next to worthless. The poor fuel pump!
Well, now it runs.....till the next time the marine gremlins pop up.
I hope others can learn from this.
A friend was having problems with the I/O engine in his Gibson houseboat. It would not idle and was hard to start. It would only somewhat idle if you hold your hand over the carb to pull more fuel. He was tempted to take it out and "blow it out" at high throttle. I didn't think that was a good idea and wanted to check a few things first. The fuel water separator was changed and I noted the fuel smelled like rank turpentine. Bingo! We checked the tank with a dipstick coated with a film of "Kolor Kut water finding paste" (modified formula!) There was a layer of ethanol at the bottom. ONLY the paste of the modified formula turns yellow in the layer of ethanol in the fuel in a few seconds. As it turns out the fuel had phased separated and the tank had to be pumped dry and lines flushed. If we had taken the boat out and ran it hard, there's a good chance the engine would have blown because ethanol runs hotter and leaner in a engine jetted for gasoline. It should be noted that he had been working on trying to get it to run so long that the water/ethanol saturated fuel had washed past the rings and turned the engine oil milky so that had to be changed. The oil stayed clear after hours of run time that confirming this.
With fresh fuel the engine ran great for about 6 hours but then it started running bad (different than before)and finally wouldn't even idle. It was acting like it was starving for fuel or vapor locked. The fuel water separator was poured out into a clear container and visually there were two different layers, about half & half. We checked both the filter's fluid and the tank with the paste and only what was in the filter had phased. Not buying that this is the soul problem I asked the owner to inspect the anti siphon valve. For some (lucky) reason he also removed the 90* elbow that goes into the pickup tube. That's when I got my biggest surprise. There was a small screen in the elbow that was packed with a 3/4" long wad of felt-like trash! A mirror was used to look into the pickup tube for more debris and it was clear. I've not seen this before but the screen was there to protect the valve, however it had so little area it's next to worthless. The poor fuel pump!
Well, now it runs.....till the next time the marine gremlins pop up.
I hope others can learn from this.
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