T
Tom Boshar
Guest
"This is my first posting on t
"This is my first posting on this site and I hope someone can help me.
I have owned a 1987 4-Winns with a 3.7 liter, 4 cylinder, 165 HP Mercruiser engine for about 5 years. It has always run well and is thoroughly winterized each fall including replacing the fuel filter at both the pump and at the carburetor (both are usually very clean). There is not a fuel/water separator installed. Fresh water use only.
Near the end of the season 2 years ago, the engine quit when attempting to reach high speed at full throttle. It restarted immediately but quit repeatedly under similar circumstances. I removed the flame arrestor and looked down into the carburetor while someone accelerated at full throttle and it looked like someone simply shut off the fuel supply to the carburetor at higher throttle. Flow from the jets just stopped. The engine will run all day at partial throttle (up to about 25 MPH) and will reach full speed for a number of seconds (the time varies) before it cuts out. If you pull back on the throttle quickly enough as it starts to die, the engine will continue to run, but will cut out again at faster speed.
I first thought fuel pump and replaced it the following spring with a factory unit. I checked the tank vent and the fuel line from the tank to the fuel pump and both were clear. It started right up, but the same problem continued. I then rebuilt the carburetor with factory parts - the problem still continues. I feel like I am missing something very simple but don’t know where to look next. If anyone has further suggestions, I’d like to hear from you.
Thanks,
Tom"
"This is my first posting on this site and I hope someone can help me.
I have owned a 1987 4-Winns with a 3.7 liter, 4 cylinder, 165 HP Mercruiser engine for about 5 years. It has always run well and is thoroughly winterized each fall including replacing the fuel filter at both the pump and at the carburetor (both are usually very clean). There is not a fuel/water separator installed. Fresh water use only.
Near the end of the season 2 years ago, the engine quit when attempting to reach high speed at full throttle. It restarted immediately but quit repeatedly under similar circumstances. I removed the flame arrestor and looked down into the carburetor while someone accelerated at full throttle and it looked like someone simply shut off the fuel supply to the carburetor at higher throttle. Flow from the jets just stopped. The engine will run all day at partial throttle (up to about 25 MPH) and will reach full speed for a number of seconds (the time varies) before it cuts out. If you pull back on the throttle quickly enough as it starts to die, the engine will continue to run, but will cut out again at faster speed.
I first thought fuel pump and replaced it the following spring with a factory unit. I checked the tank vent and the fuel line from the tank to the fuel pump and both were clear. It started right up, but the same problem continued. I then rebuilt the carburetor with factory parts - the problem still continues. I feel like I am missing something very simple but don’t know where to look next. If anyone has further suggestions, I’d like to hear from you.
Thanks,
Tom"