jamesbee19791
Cadet
- Joined
- Jul 1, 2017
- Messages
- 10
Boat is a 1996 Bayliner 2452 , Mercruiser 5.7, Alpha 1 Gen II. Partial closed cooling, electric fuel pump, Edelbrock marine carb.
Bought this boat last year, 1st time out broke down. I replaced impeller, manifolds and risers , plugs and wires. Was fine all last season, no real long runs as there was no coolant expansion tank and it was low on coolant after each run. ( my 1st boat) Had heat exchanger cleaned and it pressure tested good. Last time out last year, doing 30 it started to slowly lose power, Soon as I pulled off throttle it backfired and died. I thought it overheated, didnt look at gauge or take temp with infrared gun. Replaced thermostat, put in water , it idled fine, temps on t-stat housing showed t-stat opening , gauge fine. Never left the dock though.
I un winterized, installed coolant expansion tank and 7 psi cap on heat exchanger , changed plugs they were fouled. New fuel water seperator, no water present, only run non ethanol fuel. New water circulating pump on front of engine and new belts. Ran great on muffs, no problem. 1st run out, gets on plane then loses power, backfires, dead in water. Coolant expansion tank is full and dumped a bit in bilge. Thinking ignition issue. I replace cap, rotor, ignition module and coil. Distributor is a Pertronix flame thrower. Changed heat exchanger cap to 14 psi. Fires right up, smokes a bit, think I flooded it trying to start it last time on water. On muffs.
Put in water, Fires right up. Get on plane, starts losing power, I cut throttle, it backfires and dies. Temp on gauge is 175, at t-stat housing below the t-stat it's at 219. Coolant expansion tank again full.
Anyone have an idea? Thanks in advance!
Edit. Was only on plane a minute before losing power, heard a bearing noise from back of boat. I'm sure unrelated to this.
Bought this boat last year, 1st time out broke down. I replaced impeller, manifolds and risers , plugs and wires. Was fine all last season, no real long runs as there was no coolant expansion tank and it was low on coolant after each run. ( my 1st boat) Had heat exchanger cleaned and it pressure tested good. Last time out last year, doing 30 it started to slowly lose power, Soon as I pulled off throttle it backfired and died. I thought it overheated, didnt look at gauge or take temp with infrared gun. Replaced thermostat, put in water , it idled fine, temps on t-stat housing showed t-stat opening , gauge fine. Never left the dock though.
I un winterized, installed coolant expansion tank and 7 psi cap on heat exchanger , changed plugs they were fouled. New fuel water seperator, no water present, only run non ethanol fuel. New water circulating pump on front of engine and new belts. Ran great on muffs, no problem. 1st run out, gets on plane then loses power, backfires, dead in water. Coolant expansion tank is full and dumped a bit in bilge. Thinking ignition issue. I replace cap, rotor, ignition module and coil. Distributor is a Pertronix flame thrower. Changed heat exchanger cap to 14 psi. Fires right up, smokes a bit, think I flooded it trying to start it last time on water. On muffs.
Put in water, Fires right up. Get on plane, starts losing power, I cut throttle, it backfires and dies. Temp on gauge is 175, at t-stat housing below the t-stat it's at 219. Coolant expansion tank again full.
Anyone have an idea? Thanks in advance!
Edit. Was only on plane a minute before losing power, heard a bearing noise from back of boat. I'm sure unrelated to this.
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