performance issues

[wardhill]

Hi Folks
Finally got my 1987 seville MC in the water yesterday. The engine at idle really purrs. After about 30 minutes at full throttle the engines seems to get gas starved. Operating temp stays normal and will still motor at lower speed. dock hand thought from the sound of it it might be the impeller but there was no change in temperature. any thoughts. he engine is a 4 cyl. 165 mcm

 

[KC_Sundancer]

Hi Folks
Finally got my 1987 seville MC in the water yesterday. The engine at idle really purrs. After about 30 minutes at full throttle the engines seems to get gas starved. Operating temp stays normal and will still motor at lower speed. dock hand thought from the sound of it it might be the impeller but there was no change in temperature. any thoughts. he engine is a 4 cyl. 165 mcm

Possible clogged fuel filter and/or water seperator if it has one.

 

[Ottawamerc]

Ya I'm going with a fuel supply issue.
Scott

 

[SloBurn]

Fuel Filter.

 

[wardhill]

Thanks for the responses. I had just put a new fuel /water separator on but believe there was some old gas in the tank that wasn't good. I removed the separator filter and poured out some very discolored fluid. Put the filter back on and ran the engine again. after which i removed the separator filter and gas that came out of filter looked clean. my thought was to do this a few times to check for consistently clean gas but was concerned about how it might effect the rest of the system

 

[KC_Sundancer]

Yuck!
You may want to run something like sea-foam through it too.

 

[wardhill]

Yuck!
You may want to run something like sea-foam through it too.

added that when I fill tank with fresh gas. thinking of pouring in a bottle of Thermo-Aid for water removal

 

[Lazy Daze]

Absolutely won't be the impeller - has no impact on this scenario.

As I read through your first post, I had the same thoughts as the other guys - fuel issues. Funny enough, I was going to ask you to pull a sample of your fuel. Good thinking! KC said it best... "Yuck!". Unless you become totally positive that there starts to be nice, fresh gas being supplied I would just siphon the old stuff out and start with fresh stuff.

Also... always, ALWAYS use something like Startron. Even if you have access to E-free gas, use it. It's cheap insurance.

 

[kybishop]

I agree, it does sound and look like a fuel issue.

I would however not rule out the impeller completely. We had an issue with ours cutting out after running a bit. Ran fine idling as well. Fuel seperator and all looked fine (always run Star Tron in the fuel). The temp gauge did not register high, all looked normal. Our marine mechanic took a ride with us and he thought it seemed like symptoms of getting warm. He felt the manifolds by hand and said they were too warm and it needed an impeller. Yes he is that good, he truly is.

Put a new impeller on it and no more cutting out.