We got a 32 foot chris craft scorpion 310 with twin 235 Johnsons on it. The port side engine runs fine but we are having issues with the other.
Essentially the boat sat for 4 years and after getting both engines fired up we took it out. As stated Port just needed a few little adjustments and runs fine. Starboard would idle fine but when you went to put it on a plane it would just fall on it's face after 1200 rpms. It will cut off completely if you don't assist it with the port side motor. As long as you help it with the good motor it will run and even contributes a little but always running much less RPM and def not making the power it should.
I noticed when you put it up on plane with the port engine the starboard would rev about 1k rpm less (due to prop drag most likely) and not contribute any power, but when I opened the start solenoid by pressing in the key it picked up quite a bit. I figured the carbs were gummed up.
So I took it back to dock and after replacing the fuel filter proceeded to rebuild all three two barrel carbs getting a little gum ect out of it. All jets ended up spraying fine with carb cleaner. I put it back together and problem solved, the motor ran fine. It was getting late so we took it home. The next day I put it in the water for a short 30 minute trip and it ran fine. Next day my partner took it out and it ran fine other than running a little hot.
Well today we put it in and it would not even idle. So I opened the carbs back up finding nothing remarkable in the carbs. I figured it worked one time It would work again. After the rebuild it started and idled fine but had the same problem when you go to put it on a plane. Only difference is this time choking it does not help but slows it significantly. I'm thinking the original carb cleaning was not really the problem but in the process we did something that fixed the issue and now it's back.
Any input? Should I be looking at the fuel pump (it's a VRO engine). How would you proceed. I kind of assume it's not spark related since it ran fine for awhile. I did replace the fuel filter on the first rebuild which did nothing until we rebuilt the carbs. Pumping the fuel bulb does nothing to help under a load and I kind of thought it would if it was the fuel pump. One side of the engine def seems to run hotter than the other. I did replace both thermostats on the trouble engine and I orderd water pumps for both engines. They both **** pretty good, not a pressurized stream but a steady one.
I know they should get water pumps but when the engines are still cool I don't see why it wont go ahead and run hard at least for awhile.
I kind of ruled out timing adjustment problems b/c it ran great for a couple short 30 minute trips and did not start acting up again until it sat overnight. It idles smooth, not like it has a miss or anything.
I figure it's a fuel issue and that is also the cause of the hot running since it's lean.
Please advise.
Essentially the boat sat for 4 years and after getting both engines fired up we took it out. As stated Port just needed a few little adjustments and runs fine. Starboard would idle fine but when you went to put it on a plane it would just fall on it's face after 1200 rpms. It will cut off completely if you don't assist it with the port side motor. As long as you help it with the good motor it will run and even contributes a little but always running much less RPM and def not making the power it should.
I noticed when you put it up on plane with the port engine the starboard would rev about 1k rpm less (due to prop drag most likely) and not contribute any power, but when I opened the start solenoid by pressing in the key it picked up quite a bit. I figured the carbs were gummed up.
So I took it back to dock and after replacing the fuel filter proceeded to rebuild all three two barrel carbs getting a little gum ect out of it. All jets ended up spraying fine with carb cleaner. I put it back together and problem solved, the motor ran fine. It was getting late so we took it home. The next day I put it in the water for a short 30 minute trip and it ran fine. Next day my partner took it out and it ran fine other than running a little hot.
Well today we put it in and it would not even idle. So I opened the carbs back up finding nothing remarkable in the carbs. I figured it worked one time It would work again. After the rebuild it started and idled fine but had the same problem when you go to put it on a plane. Only difference is this time choking it does not help but slows it significantly. I'm thinking the original carb cleaning was not really the problem but in the process we did something that fixed the issue and now it's back.
Any input? Should I be looking at the fuel pump (it's a VRO engine). How would you proceed. I kind of assume it's not spark related since it ran fine for awhile. I did replace the fuel filter on the first rebuild which did nothing until we rebuilt the carbs. Pumping the fuel bulb does nothing to help under a load and I kind of thought it would if it was the fuel pump. One side of the engine def seems to run hotter than the other. I did replace both thermostats on the trouble engine and I orderd water pumps for both engines. They both **** pretty good, not a pressurized stream but a steady one.
I know they should get water pumps but when the engines are still cool I don't see why it wont go ahead and run hard at least for awhile.
I kind of ruled out timing adjustment problems b/c it ran great for a couple short 30 minute trips and did not start acting up again until it sat overnight. It idles smooth, not like it has a miss or anything.
I figure it's a fuel issue and that is also the cause of the hot running since it's lean.
Please advise.