Re: 1967 Seaflite with 302 ford engine overheating
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Originally Posted by
67seaflite
I have a 1967 seaflite with a 302 ford engine and a 280 Volvo penta outdrive.
The 280 drive was not available in 1967.
You most likely have a 200 drive.
We just bought it so I don’t know the history of the boat. It starts up and runs great however after 10 minutes or so It starts over heating when on the lake. When I run it at home in neutral it runs awesome and doesn’t over heat, even if I run it at 2000-2500 rpm for a while.
Have you replaced the water neck fitting (aka S hose connection) and the special beaded gasket underneath it?

Also, if the upper pivot tube bushing is worn out, it will cause a breach in suction.

I have pulled the thermostat out for testing purposes and that wasn’t it. The water pump on the belt drive seemed froze so I freed it up and it seems to be getting water when I open the weep hole screw.
If this is a Sherwood belt driven seawater pump, there is no weep hole screw. The screw in the housing secures the impeller cam.
I would remove the seawater pump, pull it apart and examine the interior and impeller.
Do the Volvo penta outdrive have a water impeller?
No, and never has!
Volvo Penta has always used an engine mounted seawater pump, either belt driven or crankshaft driven.
And could the water pump on the engine be the problem even though I freed it up?
There are two pumps on the engine.
One is the coolant circulating pump (looks same as what you'd see on a car/truck engine), the other will be the seawater pump.
I don’t understand boat mechanics much but I do understand car mechanics. Any help would be greatly appreciated!

Originally Posted by
67seaflite
I tore into the boat some more and changed out the impeller, it was pretty bad. after that I ran it and found that the starboard side riser was super hot and the port side was cool while running it in the driveway. So I tore the side of the manifold off to see if it was blocked and it was clear of debris, next I pulled the riser off and sure enough there was 2 pieces of rusted metal in there so I cleaned that out and put it back together. I wonder where that metal came from? Is there a flap in there or something that would be that big? It was like 3 inches long and the other piece was like 2 inches long.. definitely enough to block water flow
I doubt that this exhaust system includes risers/spacers. It most likely has manifolds and elbows only.
Post several good photos for us.
Within the exhaust manifold and elbow, there will be a seawater path. As the seawater leaves the manifold, it exits and enters the elbow through what we call "seawater transfer ports". These transfer ports are prone to becoming restricted by rust scale.
Clear the rust scale, examine the mating surfaces, and if OK, reassemble with new gaskets.
Barr, Osco, GLM and a few others offer a 3" universal style "center-rise" exhaust system for the small block Ford.
Item #1 is a manifold, items #11, #12 and #14 are elbows...... and item #16 is a spacer/riser for use in elevating the elbows.

Last edited by RicardoMarine; 07-20-2019 at 08:16 AM.
Rick ... aka Ricardo..... AQ series Volvo Penta repair
Portland, Oregon
28' SDN F/B w/ twin Volvo Penta 5.7L DP drives
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