Good Evening all,
I have a 1989 Starcraft 1701 with a 3 Litre I4 Mercruiser in it that seems to misfire when I bring the RPM up from idle, around 2500 to 4000 land and water, I believe it to be the #4 cylinder.
Things tried to fix the issue:
Replaced:
points
rotor
distributer cover
Spark plugs
spark plug wires
cleaned fuel filter in carburetor
sprayed Sea-Foam (seemed to help a bit but issue is still there, maybe placebo affect?)
Compression test showed all cylinders 145 - 150PSI
Fuel tank drained and refilled about 3 times
I have not yet tried:
Rebuild Carb (hoping for something a bit cheaper)
Check timing (no timing light)
Replace fuel pump (does the engine even have one? it should right?)
Issue started after I forgot to fill the tank up or add stabilizer but water separator doesn't seem to have anything in it, And as stated, fuel tank was drained and refilled multiple times
Im just a highschool student that is trying to help his father get his beloved boat back into working order as he spends alot of his time at work, anything that was said as I was done by my father and I together and he has some knwledge here and there about how and what to diagnose, there is a good understanding of how an engine works and what should do what, I have picked up most of my knowledge from youtube (crazy world we live in right?) from mostly the motortrend channel so my knowledge is good with how chevy V8s work, I assume it translates well into these motors too?
Thanks in advance for any and all help
I have a 1989 Starcraft 1701 with a 3 Litre I4 Mercruiser in it that seems to misfire when I bring the RPM up from idle, around 2500 to 4000 land and water, I believe it to be the #4 cylinder.
Things tried to fix the issue:
Replaced:
points
rotor
distributer cover
Spark plugs
spark plug wires
cleaned fuel filter in carburetor
sprayed Sea-Foam (seemed to help a bit but issue is still there, maybe placebo affect?)
Compression test showed all cylinders 145 - 150PSI
Fuel tank drained and refilled about 3 times
I have not yet tried:
Rebuild Carb (hoping for something a bit cheaper)
Check timing (no timing light)
Replace fuel pump (does the engine even have one? it should right?)
Issue started after I forgot to fill the tank up or add stabilizer but water separator doesn't seem to have anything in it, And as stated, fuel tank was drained and refilled multiple times
Im just a highschool student that is trying to help his father get his beloved boat back into working order as he spends alot of his time at work, anything that was said as I was done by my father and I together and he has some knwledge here and there about how and what to diagnose, there is a good understanding of how an engine works and what should do what, I have picked up most of my knowledge from youtube (crazy world we live in right?) from mostly the motortrend channel so my knowledge is good with how chevy V8s work, I assume it translates well into these motors too?
Thanks in advance for any and all help
