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TR4/4A Thinking About an Electric fan

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rnpennington

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I'm thinking about installing an Electric Fan for those times I'm stuck in really bad traffic. Normally the system cools fine, but when stuck in slow and no moving traffic for more than 20 minutes, it starts to rise. I will turn the heat and fan on and that has kept me going so far, but it made me think about this solution.


One question though (so far) - If I install a pusher mode electric fan, do I need to take off the regular fan from the engine or will they work in conjunction with one another?
 
For many years I used an electric pusher in conjunction with the stock fan. I controlled it manually and used it as you describe - slow traffic, long stop lights, railway crossings, steep slow mountain grades behind an RV, etc.

Biggest drawback -- I suspect it limited airflow when it was not in use.

In the end I removed it and installed a fan with greater pitch and blade area (first a TR6 fan, later a TR tropical fan).
 
My comment was going to be the same as Geo : It will work, but the pusher will interfere to some extent with previous airflow.

I went the other way on my TR3A & current TR3 : removed the mechanical fan entirely and installed an electric fan as a puller with automatic controller. I really like the result, no more having to keep one eye on the temp gauge while in heavy traffic!

And while I can't say I could tell the difference, I like the idea of not wasting engine power turning the fan when it's not needed. The electric runs only when stopped or moving slowly (and not all the time even then).
 
Anyone know how many cfpm is required to keep a TR3 cool? Looking a various electic fans and of course the more cfpm the larger the current draw. If I go this route, I'd really like to run my generator and not get into an alternator conversion as well. Cheers, Mike
 
The 12" Hayden I use is rated at 800 cfm in free air, 675 cfm "across a typical radiator". It's the bottom edge of what they recommend for a 2 liter engine, but seems to work well enough for me. For 2.2 liters, their recommended minimum is the 14" fan, rated at 1250 cfm free air and 1050 across a typical radiator.

Their spec is 8.8 amps for the 12", mine seems to draw closer to 8.0 as installed. The 14" is rated 11.5 amps.

The 12" actually seems to have some extra margin on my car; it only runs around 70-80% of the time during prolonged idling, even when ambient is over 100F. That's with 86mm liners (2138cc), it might have to run more if I ever get around to building a 89mm engine.
 
One question though (so far) - If I install a pusher mode electric fan, do I need to take off the regular fan from the engine or will they work in conjunction with one another?
Click to expand...

one thing about it, (especially on a 4 where you have pretty easy access), installing a pusher as a test , would be no big deal, and probably worth a try with no other modifications, since you seemed happy with performance, otherwise.

put a manual switch ( that lights up so you remember it's on) like Geo did, and you could balance battery / gen. use vs. temperature.

i followed Geo & Randall's lead.
started out with a pusher & mechanical: after awhile I went with an alt., removed the paddle fan and turned my pusher into a puller, installed an aluminum rad. & a 6 vane water pump & bellows thermostat to boot. Now I think I'd have to put her on a stove top to make the temp. gauge rise.
 
Not being a purist on mechanical specifications, I have done .....small belt conversion...harmonic balancer on crankshaft...bosch alternator....14" fan [not sure what the amps are] fitted to custom made brackets....thermo switch [with relay] fitted to the bottom radiator tank.
 
I put a Hayden pusher on my 4A and it made a big difference. The difference is that I'd have to be stuck at a summer stoplight for a good 10 minutes in 100 degree heat before I get close to the red zone, and even then it stops shy of overheating. Without it, I was regularly reaching the red zone at summer stoplights.
 
How high does it rise? Has it ever overheated?

Some rise in temp is normal of course....why not flush the cooling system and have the radiator flushed/dipped by a local radiator shop first, and install a yellow plastic fan? If your radiator has paint buildup, this can also reduce cooling performance. After doing all this, and removing the old paint I used Eastwood radiator paint. Never had any cooling issues since...but then I do live in New England.:cool:
 
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