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Thermo Electron V-Drive Overheating

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BACKDRAFT

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i've got a 1974 thermo electron v-drive behind a velvet drive transmission everything 1974 factory products.All of a sudden yesterday the V-drive felt really hot,I felt of the cooling lines and they both felt cool as though the rear circulating pump was not working. The pump on the rear is about 4"x6" or it appears to be a pump, anybody have any experience with one of these? The only thing I did different was to change the prop from A 14x16 3 blade to a 14x18 4 blade,would that make enough load difference to heat up the V-drive? I ran a 14x18 3 blade several years ago and it didn't have any effect on it.......
 
Are you sure you don't have a Walters V drive?

Anything happen that made you check the drive?

"they both felt cool as though the rear circulating pump was not working" - the hoses being cool is usually an indicator that water IS flowing thru them because the PUMP IS working...are you referring to the engine mounted, belt driven raw water pump?
 
The metal tag on the bell housing says thermo electron engine corp, v-drive serial No 18-2.274, warner gear serial No 2204. The reason I checked the V-drive is because I smelled a slight odor of gear oil. The pump I am referring to is on the rear of the v-drive,it looks like it is driven off the rear of the top gear of the v-drive,its rectangular about 4"x6" and both cooling lines run out of it,it is about 1" thick and has about 4 bolts holding it on........I also saw a v-drive on ebay that said it was a thermo electron that looked just like it but not the same exact model.........
 
Well i went to the river the other day and disconnected the cooling lines and it was not pumping any gear oil through the pump at all,so i guess i will take the pump off the rear of the v-drive and see what i can find in there. I have no idea how it operates may be a gear drive pump? Does anyone out there have any experience with one of these ??
 
Any chance you can post a picture of the V-drive?? I have V-drives but the water that cools them comes from an engine driven pump. The V-drives are self contained with internal oil for lubrication , no oil to pump anywhere.

This is a photo of a "spare" V-drive and is what I have in my boat V-Drive.jpg
 
BACKDRAFT said:
i've got a 1974 thermo electron v-drive behind a velvet drive transmission everything 1974 factory products.All of a sudden yesterday the V-drive felt really hot,I felt of the cooling lines and they both felt cool as though the rear circulating pump was not working. The pump on the rear is about 4"x6" or it appears to be a pump, anybody have any experience with one of these? The only thing I did different was to change the prop from A 14x16 3 blade to a 14x18 4 blade,would that make enough load difference to heat up the V-drive? I ran a 14x18 3 blade several years ago and it didn't have any effect on it.......
Click to expand...


I would have thought that when you go from the 3 blade to a 4 blade prop you should have dropped the pitch instead of increasing it. Does the engine run up to rated rpm at full throttle? If not, you may be placing too much load on the engine and drive train as a whole and it could cause an overheat condition.
 
My V-drive looks just like the picture but it is a little bigger with a sump on the bottom to hold the extra grease.The cooling lines come off the cooler witch is the first cooler to get water from the river about two feet from the pick-up. The cooler looks to be driven on the rear of the v-drive top gear and circulates grease through the cooler witch is about 8 to 10 inches long. If you drew a straight line from where your transmission hooks up to the rear of the v-drive thats where the pump is located about 4x6 inches 3/4 inch thick one line coming in one line going out to cooler,85w-90w gear oil.
 
Ok here is an update to the v-drive problem, pump is off and it had locked up at some point and rounded off the end of the shaft that drives it off of the back of the gear..It had a couple of burrs on the gears I filed them back smooth and they turn fine now. found a new pump at the Tuthill Corporation thats where the origional was from,should be back in action real soon.
 
I'm glad you are getting to the bottom if it. That said, adding 2 inches of pitch and going to a 4 blade prop is adding a lot. If you can turn up to rated rpm you are good though.
 
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