surfsidewood
Seaman Apprentice
- Joined
- Dec 4, 2009
- Messages
- 30
Hi I have a 2003 Mercury 225 4 stroke (Yama-Merc) that I just bought used and put on my 1990 22' Hydra Sports. I took the old motor off, drained most of the premix fuel except for about 10 gallons and added about 60 gallons to the tank with fresh fuel.
When throttling up it just bogs down and every once in a while backfires through the intake. I can find a spot on the throttle where it will run smooth, but this spot is never in the same range. Sometimes I can get it wide open and run for 30 minutes, sometimes I can't even get to 1000 rpms. It's acting like it's running out of gas.
Replaced the entire fuel line from tank to motor, new fuel/water separator, new fuel filter on motor, and a new filter on the vent line for the vst. The only filter I haven't changed is the one inside the VST on the bottom of the fuel pump. Listened to the injectors and they sound fine.
The fuel tank is plastic tank and does not leak. The cap has a rubber o ring in place. The vent is clear. Old motor never had any problems with fuel. I usually always add stabilizer to the fuel. If it was the VST filter wouldn't it just be stopped up all the time? Is there anything it could be that I'm not thinking of to cause a problem like this? I wanted to make sure before I go and spend another $100 on the vst filter.
Should I be concerned about these Compression numbers?:
#1- 150
#3- 150
#5- 175
#2- 175
#4- 170
#6- 160
Fuel pressure reading 44 psi
Sorry for the lengthy post, but this is driving me absolutely nuts and I just want to go fishin.
Any help would be greatly appreciated.
When throttling up it just bogs down and every once in a while backfires through the intake. I can find a spot on the throttle where it will run smooth, but this spot is never in the same range. Sometimes I can get it wide open and run for 30 minutes, sometimes I can't even get to 1000 rpms. It's acting like it's running out of gas.
Replaced the entire fuel line from tank to motor, new fuel/water separator, new fuel filter on motor, and a new filter on the vent line for the vst. The only filter I haven't changed is the one inside the VST on the bottom of the fuel pump. Listened to the injectors and they sound fine.
The fuel tank is plastic tank and does not leak. The cap has a rubber o ring in place. The vent is clear. Old motor never had any problems with fuel. I usually always add stabilizer to the fuel. If it was the VST filter wouldn't it just be stopped up all the time? Is there anything it could be that I'm not thinking of to cause a problem like this? I wanted to make sure before I go and spend another $100 on the vst filter.
Should I be concerned about these Compression numbers?:
#1- 150
#3- 150
#5- 175
#2- 175
#4- 170
#6- 160
Fuel pressure reading 44 psi
Sorry for the lengthy post, but this is driving me absolutely nuts and I just want to go fishin.
Any help would be greatly appreciated.
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