easyrider1340
New member
New hear, but reaching out for some assistance.
This issue has been well documented at http://www.offshoreonly.com/forums/...575-sci-back-flushing-method-need-advice.html
However, I'm still having a low water pressure and overheating condition on this engine.
Current situation is....
- temps running about 20~30 degrees hotter than spec (120* thermostat)
- about 3~4 psi water pressure while under way / on plane
- new sea pump assembly (housing, impeller, oring, quad ring)
- coolers are free of restrictions
- replaced water outlet gasket
- replaced sea pump inlet hose
- transom water insert is not collapsed and confirmed ok.
- I dropped the lower gear housing and confirmed no trash in water inlets
These engines have a history of blowing head gaskets, so that is always in the back of my mind when troubleshooting this issue.
In neutral while in the water, I can rev the engine up to about 2500 rpm and get 8~10 psi of water pressure.
While underway or while getting up on plane, water pressure dips to approximately 3~4 psi and remains there.
I replaced one of my thermo to exhaust hoses with clear tubing. At idle in the water, there are some bubbles in the system. When getting on plane, and on plane - the bubbles were MUCH higher concentrated - almost solid bubbles.
https://www.youtube.com/watch?v=46LrkmxAHWw
Thinking back to head gasket, the bubbles seems to correlate. However, I did not place the hose prior to the thermo housing. So I'm second guessing the head gasket, and thinking about the drive. Could the drive be sucking air somewhere?
This problem started last year - prior to that, everything ok.
This issue has been well documented at http://www.offshoreonly.com/forums/...575-sci-back-flushing-method-need-advice.html
However, I'm still having a low water pressure and overheating condition on this engine.
Current situation is....
- temps running about 20~30 degrees hotter than spec (120* thermostat)
- about 3~4 psi water pressure while under way / on plane
- new sea pump assembly (housing, impeller, oring, quad ring)
- coolers are free of restrictions
- replaced water outlet gasket
- replaced sea pump inlet hose
- transom water insert is not collapsed and confirmed ok.
- I dropped the lower gear housing and confirmed no trash in water inlets
These engines have a history of blowing head gaskets, so that is always in the back of my mind when troubleshooting this issue.
In neutral while in the water, I can rev the engine up to about 2500 rpm and get 8~10 psi of water pressure.
While underway or while getting up on plane, water pressure dips to approximately 3~4 psi and remains there.
I replaced one of my thermo to exhaust hoses with clear tubing. At idle in the water, there are some bubbles in the system. When getting on plane, and on plane - the bubbles were MUCH higher concentrated - almost solid bubbles.
https://www.youtube.com/watch?v=46LrkmxAHWw
Thinking back to head gasket, the bubbles seems to correlate. However, I did not place the hose prior to the thermo housing. So I'm second guessing the head gasket, and thinking about the drive. Could the drive be sucking air somewhere?
This problem started last year - prior to that, everything ok.