I have a 1989 sea sprite came from the factory with a 4.3L 175hp Alpha drive
I bought it with a cracked block.
Now the boat has a new reman 350 Gen+ (center bolt valve covers non vortec) Marine engine 4bbl air gap aluminum intake.
New Manifolds and 4" risers with the restricted riser gaskets (2 large 2 small holes)
New Marine specific circulating pump
New Impeler with new upper and lower housings
New 140 Thermostat and had housing sandblasted inside. Thermostat is the gen 3 with cooling hoses going to risers and manifolds
Silent choice exhaust.
When idling in my shop on the hose it will come up to temp and run 135 -142 on my temp gun
Exhaust manifolds sit right around 135
Starbord side riser is at 88 port runs about 100
The exhaust/water that dumps at the lower gimbal housing will be cold on starbord and 130 on port.
I get equal water flow from both sides of the gimbal housing but when silent choice is opened up water flows out starbord but very little out of port.
Port exhaust diverter sits at 90 and the starbord will climb to 135
Cylinder head temps at stern are both 120-130 Head temp at front of engine is 135 on both sides.
All temps stay the same with silent choice open or not
The motor never overheats nor has it ever been.
Am I overthinking this water flow or is there an issue.
Thanks in advance.
Jon
I bought it with a cracked block.
Now the boat has a new reman 350 Gen+ (center bolt valve covers non vortec) Marine engine 4bbl air gap aluminum intake.
New Manifolds and 4" risers with the restricted riser gaskets (2 large 2 small holes)
New Marine specific circulating pump
New Impeler with new upper and lower housings
New 140 Thermostat and had housing sandblasted inside. Thermostat is the gen 3 with cooling hoses going to risers and manifolds
Silent choice exhaust.
When idling in my shop on the hose it will come up to temp and run 135 -142 on my temp gun
Exhaust manifolds sit right around 135
Starbord side riser is at 88 port runs about 100
The exhaust/water that dumps at the lower gimbal housing will be cold on starbord and 130 on port.
I get equal water flow from both sides of the gimbal housing but when silent choice is opened up water flows out starbord but very little out of port.
Port exhaust diverter sits at 90 and the starbord will climb to 135
Cylinder head temps at stern are both 120-130 Head temp at front of engine is 135 on both sides.
All temps stay the same with silent choice open or not
The motor never overheats nor has it ever been.
Am I overthinking this water flow or is there an issue.
Thanks in advance.
Jon
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