" 1978 MerCruiser 470 4 cylind
" 1978 MerCruiser 470 4 cylinder
We were on the water the other day and our tach started jumping all over the place then the motor cut out 3 or 4 times. It finally quit and when we tried to start it, the engine wouldn't even turn over. We waited a few seconds then it started fine but we had to limp it home at low speed. Also, whenever we went ovrsomeone else's wake, our gauges jumped around and the fuel gauge dropped all the way to Empty. Once the boat levelled out, they were fine (the tach was still jumping some but not as bad at low speed and the guages have never done this before).
We checked our boat's charging system and it doens't seem to be charging. We checked the battery and the volts run in the low 12's running and mid 11's when it's shut off.
We thought it might be our rectifier but we were told that they don't make rectifiers for this year boat anymore? We're also wondering what voltage test we can do on the rectifier, voltage regulator and stator so we can determine which one is bad? Our voltage regualator was changed 3 years ago; would it go bad this quickly?
On a similiar note: When we first used the boat this year it wouldn't start (no spark). We traced everything and ended up replacing our cellenoid, coil, points and condenser (they all tested bad), plugs, roter and distributor cap. It ran fine last year when we put it away. What could have burned the low end electrical equipment? It's an old boat and we thought it was just bad luck that it all went out at once, but now we're wondering.
Any help would be greatly appreciated! We're in the process of getting a manual for this boat but we don't have it yet (we've only had the boat a year and have absolutely no problems until now). "
" 1978 MerCruiser 470 4 cylinder
We were on the water the other day and our tach started jumping all over the place then the motor cut out 3 or 4 times. It finally quit and when we tried to start it, the engine wouldn't even turn over. We waited a few seconds then it started fine but we had to limp it home at low speed. Also, whenever we went ovrsomeone else's wake, our gauges jumped around and the fuel gauge dropped all the way to Empty. Once the boat levelled out, they were fine (the tach was still jumping some but not as bad at low speed and the guages have never done this before).
We checked our boat's charging system and it doens't seem to be charging. We checked the battery and the volts run in the low 12's running and mid 11's when it's shut off.
We thought it might be our rectifier but we were told that they don't make rectifiers for this year boat anymore? We're also wondering what voltage test we can do on the rectifier, voltage regulator and stator so we can determine which one is bad? Our voltage regualator was changed 3 years ago; would it go bad this quickly?
On a similiar note: When we first used the boat this year it wouldn't start (no spark). We traced everything and ended up replacing our cellenoid, coil, points and condenser (they all tested bad), plugs, roter and distributor cap. It ran fine last year when we put it away. What could have burned the low end electrical equipment? It's an old boat and we thought it was just bad luck that it all went out at once, but now we're wondering.
Any help would be greatly appreciated! We're in the process of getting a manual for this boat but we don't have it yet (we've only had the boat a year and have absolutely no problems until now). "