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TR4/4A TR4 Water Pump Extra Vane

KVH

Obi Wan
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Is it possible that the extra vane pump I bought pushes the water through the radiator too fast, and that the performance is actually worse, causing more overheating?

I'm beginning to suspect a problem, as I seem to be running hotter not cooler.

Thanks all.
 
No, I don't think the heat transfer would work that way. If it were too slow, the pump might be the limiting factor. Too fast and you are limited by the ability of the radiator to transfer heat. Bear in mind that if you think it is leaving the radiator too fast, it is also pulling from the engine faster, too. Fast is fine, I think.
 
Thermostat should control water flow through the engine and, therefore, the radiator. If water is allowed to flow too quickly, the engine will ovwerheat. Check and change, if necessary, the thermostat. That should cure the overheating. If, not, check that the radiator fins and tubes are not being blocked with foreign matter.
Is the radiator duct in place and fairly well sealed to the rad?
 
Before I pulled the head and replaced the head gasket last fall I had used a variation of Barsleak that said it could react and clog the radiator if I didn't first flush the system. I did flush it, but maybe not well enough. Maybe I clogged the tubes? I did have quite a bit of that fiber to wash out when I rebuilt everything last fall. I used a commecial flush twice so that really would surprise me, but maybe that's my issue here.
 
I have never been convinced that an extra vane (extra vain?) pump was an advantage. I have heard some suggestions that it is less effective -- moving water too fast was one reason, additional cavitation another.

As they say... without data it's just another opinion.

I have a spare water pump you can borrow if you want to try an experiment (easier to R&R the pump than the radiaotr I think).

BTW -- I have seem some repro pumps with shallower vanes than the originals... I do suspect those would be inferior.
 
Thanks, Geo, I'll add this to my list of "if it ain't broke" violations and transgressions. I really must say that the very first day of running with that "extra efficiency" design had me wondering when my electric fan kicked in after only a short drive, albeit in 100 degree heat. Still, I think it might not be allowing the water to stay in the radiator long enough. Either that or I did clog the radiator with that Barleak compound.

I'll give some thought to putting another back in.

I still marvel at the simplicity and efficiency of these engines. If the timing were right I'd own another. thx
 
Kentvillehound said:
Still, I think it might not be allowing the water to stay in the radiator long enough.
Nope, no such thing. If the water moves faster through the radiator and so loses less heat, it also moves faster through the engine and picks up less heat. The total heat moved doesn't go down.

But without the thermostat, the high pressure side of the pump is connected to the top of the radiator, which is where the pressure cap is located. Those pumps can produce 30 psi or more if the flow is restricted, and the radiator tubes represent some restriction even if they aren't clogged with deposits and Bars-Leak. The resulting pressure may well be enough to blow water past the radiator cap; which would of course lead to overheating.

I believe this is "root cause" for all the myths about moving water through the radiator "too fast".
 
I'm unfamiliar with the pump you're talking about, however I do have a related anecdotal observation.

On the A-series engines for BMC cars there are problems with high-flow pumps moving water through the radiator "too fast" resulting in higher engine temperatures. The fix on racing engines is to use a larger pump pulley to slow the pump down.

Though I studied heat transfer years ago it was one of my weak subjects. Heat/mass transfer always eluded me.
 
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