1967 Seaflite with 302 ford engine overheating

67seaflite said:

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!

Click to expand...

67seaflite said:

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.

Click to expand...

67seaflite said:

So I have replaced the sea water impeller, it was pretty bad.

I will I’ll check the S hose connection. That does make sense though, if that is leaking it could be sucking air and not all the water creating water problems. So thanks for that.
The water neck fitting is aluminum, and is a wear item. It is common that this part needs routine replacement.

i believe someone must have put a penta 280 on here after 67 because that’s what the outdrive cover says on it.
Owners forget to properly tighten the upper locking device, and will eventually lose this cover.
Since all of the 200, 250, 270, 280, 285, 275 and early 290 covers fit, there is no guarantee that the emblem matches the drive.


i figured out that the part that arced out was a inline 40 amp breaker. Replaced that now it turns over again.

i pulled the exhaust manifold apart and the elbow apart and the elbow (I thought it was called a riser) was clogged with those pieces of metal so I removed them and put the exhaust back together. I can’t find any information on these manifolds or where to get gaskets for them so I used gasket maker for the time being. (I will buy some newer ones like pictures above for next season but to finish out this summer I went this route. So hopefully it all works out
Be careful..... gasket maker will blow out, and you will have a breach here.

the last question I had is that there are about 5 petcocks on the bottom of the elbow and engine for winterizing I assume and 2 out of the 5 leak water, can I plug them with a brass fitting of some sort instead or do I need to keep them the petcock style?

The Petcock style drain plugs should NOT be used. They do not offer a means of probing the opening to remove rust scale that may prevent all water from draining.
Instead, use the Marine style drain fittings with a removable stop.
Or like Mark suggests, plain old tapered pipe thread brass plugs.

Click to expand...

67seaflite said:

every time I hit upload picture nothing happens so I might be out of luck

Click to expand...