mowinkid37
Cadet
- Joined
- Jun 14, 2021
- Messages
- 8
This one is my first post here and is a story so i appreciate the read...
TLDR: engine wont rev past idle and sounds like its choking out.
Engine: 1998 5.7L Mercruiser with a 2BBL carb.
I bought this boat from a good friend who never had engine issues with it but hadn't ran it in 3 years. When i started it up for the first time this spring, i emptied the fuel filter, filled it with fresh gas, then hooked it up to a jerry can with fresh gas (93) and seafoam and the thing ran mint. idled, revved, ran perfect. i ran it out of gas and then left it for a week.
when i ran it the next week. it was again off of a jerry can with fresh gas, 360 marine stabil, and seafoam. the engine would start but would not rev. it got to temperature and still wouldnt rev. every time i tried to rev it, it sounded like it wasnt getting fuel/choking out. then all of a sudden, it started running perfect. idle, rev, run at high rpms, no issues. I figured i just sucked some gunk through the carb and that was that.
The week after i fully drained the inboard tank and filled it with 360 marine stabil and 10 gallons of 93. i also replaced the fuel filter/water seperator with a merc filter. this time the engin would run/idle but not rev again. i waited to see if it would do what it did previously, but it didnt.
Im wondering if it is a carb issue or a fuel pump issue. idk if the mechanical fuel pumps work intermittently. also, are there any other fuel filters inline? i dont think there is one in the tank but maybe one in the carb inlet? really bummed i cant have this thing on the water. any help would be great. also, any opinon on rebuild/buy new carburator. if the latter, any good suggestions?
Thanks again for reading this novel!
TLDR: engine wont rev past idle and sounds like its choking out.
Engine: 1998 5.7L Mercruiser with a 2BBL carb.
I bought this boat from a good friend who never had engine issues with it but hadn't ran it in 3 years. When i started it up for the first time this spring, i emptied the fuel filter, filled it with fresh gas, then hooked it up to a jerry can with fresh gas (93) and seafoam and the thing ran mint. idled, revved, ran perfect. i ran it out of gas and then left it for a week.
when i ran it the next week. it was again off of a jerry can with fresh gas, 360 marine stabil, and seafoam. the engine would start but would not rev. it got to temperature and still wouldnt rev. every time i tried to rev it, it sounded like it wasnt getting fuel/choking out. then all of a sudden, it started running perfect. idle, rev, run at high rpms, no issues. I figured i just sucked some gunk through the carb and that was that.
The week after i fully drained the inboard tank and filled it with 360 marine stabil and 10 gallons of 93. i also replaced the fuel filter/water seperator with a merc filter. this time the engin would run/idle but not rev again. i waited to see if it would do what it did previously, but it didnt.
Im wondering if it is a carb issue or a fuel pump issue. idk if the mechanical fuel pumps work intermittently. also, are there any other fuel filters inline? i dont think there is one in the tank but maybe one in the carb inlet? really bummed i cant have this thing on the water. any help would be great. also, any opinon on rebuild/buy new carburator. if the latter, any good suggestions?
Thanks again for reading this novel!
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