wpowell323
Petty Officer 3rd Class
- Joined
- Mar 29, 2009
- Messages
- 75
I have a 2003 Monterey 228 SI with a Mercruiser 350 MPI and a Bravo drive. At anything about about 4000 rpm's up to WOT the motor will creep up to 200 degrees and alarm. When this happens I can shoot the motor with a thermometer and the lower block is about 170, that manifolds are about 180-190, and the risers are like 100 but the thermostat housing is 200 or more. I have replaced the thermostat and run it with or without the thermostat and it still does the same thing. The sea water impeller and housing are new. The block waterpump has been replaced. The drive has been freshly sealed. The fitting where the water comes through the gimbal housing has been replaced. The red hose from the gimbal housing to the seawater pump is new. I have removed and inspected the manifolds and risers and both seem to be fine with little to no corrossion. According to the DDT my PSI is 18-20, I think Mercury reccomends 25 psi, but i have no idea how to get it to increase and it seems with 20 psi it should be fine. I have done everything i can think of short of welding a bob's low water pickup to the gearcase or making it a closed cooling system. Hopefully someone here can help or has expreienced something similar.
ENG: 0M619908 Model # 4442067RS MERCRUISER 350 MAG BRAVO MPI, Engine Manufacture Date was on 11/20/2002.
DRV: 0M162606 Model # 5231200N1 MERCRUISER BRAVO 1 1.50:1
TRN: 0M564540 Model # 6211001N1 MERCRUISER BRAVO TRANSOM
ENG: 0M619908 Model # 4442067RS MERCRUISER 350 MAG BRAVO MPI, Engine Manufacture Date was on 11/20/2002.
DRV: 0M162606 Model # 5231200N1 MERCRUISER BRAVO 1 1.50:1
TRN: 0M564540 Model # 6211001N1 MERCRUISER BRAVO TRANSOM
