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Cooling fan options

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TR3sharon

TR3sharon

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In the process of diagnosing my overheating issue, I discovered that one of the blades on the stock 4 blade fan was bent. Unfortunately, no one appears to carry a new assembly and the upgrade TR6 8 blade fan is currently unavailable.
I'm concerned that if I just straighten the existing blade that it may lead to trouble down the road (literally) due to balance issues.
Has anyone found a suitable replacement?
 
TR3sharon said:
...I'm concerned that if I just straighten the existing blade that it may lead to trouble down the road (literally) due to balance issues...
Click to expand...

I agree:

Fan%20x%202.JPG


After my TR4 broke the 2nd one I went with a tropical fan. In addition to more blades and greater pitch it also has much less aluminum sticking out beyond the steel arms which should make it much less likely to flex & break.

TropicalFan.jpg


Another bolt-on alternative is a used TR6 fan -- fairly widely available in good used condition. I actually used one for awhile before getting the tropical fan but didn't care for the look and gave it away (the fan is very noticeable on a TR4, not so much so on a TR3).
 
I guess I'm confused. TRF seems to have both the TR3 and TR4 fan listed as being in stock. Did they tell you otherwise?
 
KVH said:
Geo, where did you find that "tropical fan," and is it working great?
Click to expand...

Found them here on the Forum by asking (that is a well-known Forum member's hand in the photo). They're rare but not totally unobtainium.

They work very well.

For years I had electric 'pushers' on both TRs with a manual switch as I would only use them to help out when stuck in traffic or behind a 35' Winnebago going up Mt Lemmon.

After installing the tropical fans I found those auxillary electrics were unnecessary and have removed them altogether.

BTW -- the said electric fans (and mounting hardware) are 'free to good home' if anyone is inclined to go that route.
 
In the "for what it's worth" department:

TeriAnn's site refers to the replacement grills reducing air flow by about 25% compared to the original grills, due to the "wider" cross slats (and resulting narrower grill openings).

"Reproduction TR3A grills have smaller openings and wider cross slats. The space between the TR3A grille bars is about 24% smaller on reproduction grilles. This results in less air flow to the radiator which can make the difference in warm weather. So wherever possible reuse or obtain a good used original TR3A grill."

https://www.tr3a.info/bodywork.htm

Tom
 
NutmegCT said:
...Reproduction TR3A grills have smaller openings and wider cross slats...
Click to expand...

By way of illustration: Top pic is the repro grille I used to have and below an original grille. Yes it's the same car and same red paint, just different camera.

grilles.JPG


Difference is most noticeable (at this distance) by comparing some of the small openings.
 
TR3driver said:
I guess I'm confused. TRF seems to have both the TR3 and TR4 fan listed as being in stock. Did they tell you otherwise?
Click to expand...

I only checked with Moss and another smaller retail website. TRF's site aggravates me so I didn't check there. I will be giving them a call first thing in the am
 
NutmegCT said:
"Reproduction TR3A grills have smaller openings and wider cross slats.
Click to expand...

FWIW, I believe the problem is mostly that the slats aren't crimped as far. With care, you can deepen the crimp and get openings as large (or even slightly larger) than the original.

Even TeriAnn thought it was an original grille :smile:
 
TR3sharon said:
TRF's site aggravates me
Click to expand...

The secret to dealing with TRF's site is to have a copy of the factory parts catalogue for your car. With that in hand (I keep toolbar icons for both the TR3 and TR4 version), their site becomes very easy to use (at least for me). (Of course, practice might have something to do with it as well, seems I put in an order every month or two and always through the web site.)

Charles has been promising us a full TR3 and TR4 catalog for many years, but I don't see it happening any time soon. Maybe one of his sons will get it done, after Charles retires.

https://docs.google.com/open?id=0B2H2NJt34OffMWQ4N2EzZGQtNjc0Ny00YmE2LWFiN2UtZWYzMjNjNGFiYzY4

https://docs.google.com/open?id=0B2H2NJt34OffYjZmY2ZlYzctYzg5OC00OTc4LWE3MmEtMmRiODI3OTliY2Y4
 
TRF hooked me up with an original style fan, but it's coming from across the pond. Beggers can't be choosers. FYI, the upgrade TR6 fan is being reproduced but they are several months away from completion.

Thanks for the spare parts .pdf
 
Good comparison pic Geo.
Has anyone tried running with no grill on a hot day to see how much grill restrictions matter?
John
 
I live in Northern California where Summer temps can often top 100. When I restored the Red Head (60 TR3A) we built it with a stock engine mainly so I could try and not have the overheating problems. The other cars around here were all built with larger pistons etc. Guess who is always fighting overheating! Me! I had the radiator redone taking out the crank hole...just a little help. Added a pusher fan...just a little help. Thinking of this Winter of going with a aluminum radiator!
At this time on flat highway....she runs 185 to 190...but just let the car see a hill up ahead and the temp starts to climb! Gil NoCal
 
I'm always interested in these fan topics.

I have the original engine and radiator. I drive at speed (60+) and never see the gauge go over 185 until I park and shut off the engine - or just let it sit and idle in hot weather. That's when it *may* go up to 190.

I also crimped the grill slats as Randall refers to. Decided to do that when I read TeriAnn's article about the 25% reduction.

To my ol' brain, a new radiator and electric fan may not fully overcome the 25% reduction in air flow that results from having the replacement grill.

Tom
 
tom,
How did you do the grill crimping? I looked at my grill last night and couldn't visualize how I could do that without making a mess of it.
John
 
NutmegCT said:
To my ol' brain, a new radiator and electric fan may not fully overcome the 25% reduction in air flow that results from having the replacement grill.
Click to expand...
I'm inclined to agree, at least with the electric fan. The fan really does nothing when the car is moving above 20-30 mph; but the size of the slats is primarily an issue at higher speeds. The airflow (and cooling) requirement goes up with engine power output, and it takes a lot more output to hold 75 mph than 35 mph. (Roughly 8 times as much, it's a cube function.)

But if your old radiator is crudded up inside (not even necessarily blocked, just deposits that block heat transfer between water and tubes); then a new radiator core is going help across the board. Might be enough, might not.

To crimp the slats, I (carefully) used "linesman pliers", which have a wide jaw with parallel serrations across the jaw. It might have been better to stuff something between the jaws to limit how far they could close, but I did it freehand. Results came out good, there were only some very small marks in the corners that were more or less unnoticeable. But my TR will never be a show car, it's not something I'd want to try to pass a concours judging with.
 
Randall - I think I used a similar technique. Here's the pliers, and a closeup. I put leather inside the pliers to "soften the blow".
 
Can anyone tell me why these fans are so different? The original is on the right. The new one is significantly wider. In addition, the new one arrived with a bend in one of the fins, so now I have to equip the old fan since I don't have the 4 weeks to wait for another to be shipped. I may just go the plastic fan route, backordered or not.

84599771@N04


flickr
 
Near as I can tell, the one on the left is a TR4 fan; on the right is a TR3.
 
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