2001 Optimax 135. 0T363758. Idles rough. Runs great. Fuel rail and cylinder head temps seem high. I just mounted motor and no gauges are in use right now, but the ones I have would help anyway.
Rails and heads are hot to the touch. 3-5 seconds touch and I need to pull fingers of. The Portside fuel rails stay somewhat cool because water flows through it..not sure why they don't route water thru the starboard rail too. So I'm sure the fuel has to be overly warm if not hot.
Cooling system: New thermostats, water pump, poppet valve. Water is flowing as I checked every hose-end I could.
Fuel: New fuel filter, machanical fuel pump ( the square one).
Oil: System is functioning, draws oil into reservoir and the the inline filter. Change Air filter as well.
New plugs: Went with what was in motor when I got it. Iridium PZFR5G .031"(Manual calls for PZFR5F
(.040" gap), not sure if the smaller gap I'm running can influence temps drastically. The last owner did a lot of trolling at 2000-2500rpm, supposedly the Iridium is better for low RPM use.
Not sure what do next?? I'm kind of resurecting this motor. It runs great, spark is solid, compression is solid, hole shots are amazing. It pushes my 17' aluminum bass boat 45+mph and I suspect it should go much fast per the charts in the service manual...myboat only weighs about 1,500lbs. I just don't want to blow the damn thing up because of overheat. I have not completed the entire keyswitch and throttle wiring yet so my tach isnt up and running.
Any suggestions on why these heads rails are hot would be appreciated! Like I say water flow seems to be abundant as well as entirely new. Would a faulty or stuck air or fuel injector somehow back up the system and heat the fuel in the rail..I know I'm grasping at straws but short of hooking this thing up to DDT I cant tell exactly what injector is bad, if any.
Thanks once again.
Rails and heads are hot to the touch. 3-5 seconds touch and I need to pull fingers of. The Portside fuel rails stay somewhat cool because water flows through it..not sure why they don't route water thru the starboard rail too. So I'm sure the fuel has to be overly warm if not hot.
Cooling system: New thermostats, water pump, poppet valve. Water is flowing as I checked every hose-end I could.
Fuel: New fuel filter, machanical fuel pump ( the square one).
Oil: System is functioning, draws oil into reservoir and the the inline filter. Change Air filter as well.
New plugs: Went with what was in motor when I got it. Iridium PZFR5G .031"(Manual calls for PZFR5F
(.040" gap), not sure if the smaller gap I'm running can influence temps drastically. The last owner did a lot of trolling at 2000-2500rpm, supposedly the Iridium is better for low RPM use.
Not sure what do next?? I'm kind of resurecting this motor. It runs great, spark is solid, compression is solid, hole shots are amazing. It pushes my 17' aluminum bass boat 45+mph and I suspect it should go much fast per the charts in the service manual...myboat only weighs about 1,500lbs. I just don't want to blow the damn thing up because of overheat. I have not completed the entire keyswitch and throttle wiring yet so my tach isnt up and running.
Any suggestions on why these heads rails are hot would be appreciated! Like I say water flow seems to be abundant as well as entirely new. Would a faulty or stuck air or fuel injector somehow back up the system and heat the fuel in the rail..I know I'm grasping at straws but short of hooking this thing up to DDT I cant tell exactly what injector is bad, if any.
Thanks once again.
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