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TR2/3/3A TR3A Fan Blade Conversion

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Gentlemen,

As part of my back and forth with Mark Macy on his new fan (which I ordered) he provided his view of the bellows thermostat as follows:

"We install the bellows thermostats in every car and engine webuild, probably about 30 a year. We have had only one failure in the pasttwo years, so overall they are pretty reliable. I will mention that thelarge OD flange is slightly oversized and may not seat perfectly in the recessof some water outlet housings, and we have to check closely and sand down thisflange to get them to seat properly. It is possible that some of thefailures could be caused by this flange getting "tweaked" if itdoesn't seat correctly, and possibly put the bellows assembly in a bind. Whether you use the sleeved thermostat or block the bypass, you have to slow orstop the return of hot water to the block if you want these cars to runcool. If you go with the blocked bypass, then by all means be sure todrill a 1/4" hole in the plug so that some water can flow and prevent airpockets."

Regards,

Walter
 
Walter, you state that you are doing a frame off...in that case instead of replacing the extension consider mounting the radiator slightly forward for the needed clearance.
Re: TR4's, one can use a TR3 extension which is shorter than the TR4 extension rather than mounting the fan backwards.
Bob
 
Bob,

Thanks for the suggestion, but clearance on either car is not an issue with the Macy fan I bought. It uses all of the stock hardware, including the original hub extension (without reversing the fan!).

Regards,

Walter
 
Tropical TR said:
Sorry, meant to add that if anyone is interested in the information Mark Macy sent me, would be happy to provide it in a private mail. Regards,

Walter
Click to expand...

Hi Walter,

I too would be very int. in Mark`s info.

Thanx, Russ
 
Tropical TR said:
Gentlemen,

As part of my back and forth with Mark Macy on his new fan (which I ordered) he provided his view of the bellows thermostat as follows:

"We install the bellows thermostats in every car and engine webuild, probably about 30 a year. We have had only one failure in the pasttwo years, so overall they are pretty reliable. I will mention that thelarge OD flange is slightly oversized and may not seat perfectly in the recessof some water outlet housings, and we have to check closely and sand down thisflange to get them to seat properly. It is possible that some of thefailures could be caused by this flange getting "tweaked" if itdoesn't seat correctly, and possibly put the bellows assembly in a bind. Whether you use the sleeved thermostat or block the bypass, you have to slow orstop the return of hot water to the block if you want these cars to runcool. If you go with the blocked bypass, then by all means be sure todrill a 1/4" hole in the plug so that some water can flow and prevent airpockets."

Regards,

Walter
Click to expand...

We use a 1/2" copper pipe cap with a 3/8" drilled hole in the center. It fits snugly inside the return hose on its own. Cost is cheap cheap
 
I still prefer the tr7 fan. You simply cut off the old paddle blades and drill
holes in the stumps(after some prep work) bolt it on.Fits perfectly costs nearly nothing
and solves all the cooling issues.The added advantage is that by saving the original fan hub
you retain the slight dampening effect of the rubber mounted fan.....
MD(mad dog)
 
John_Progess said:
Croz,
Moss sells a blanking sleeve for the MGA thermostat. I have them on my MGA's. I will check and see if the housings are about the same so maybe it will fit the TR 3.

John
Click to expand...

Thanks John. It will be another month or two before the car sees daylight.
Steve
 
PeterK said:
We use a 1/2" copper pipe cap with a 3/8" drilled hole in the center. It fits snugly inside the return hose on its own. Cost is cheap cheap
Click to expand...

I use a 3/4" copper cap & a 3/16" hole.

bypasshose_zpsc06926c1.jpg


Shoot, for many years I used a piece of broomstick with no hole -- can't really recommend that but greatly restricting that bypass does seem to improve cooling.
 
Geo Hahn said:
I use a 3/4" copper cap & a 3/16" hole.

bypasshose_zpsc06926c1.jpg


Shoot, for many years I used a piece of broomstick with no hole -- can't really recommend that but greatly restricting that bypass does seem to improve cooling.
Click to expand...

My foggy brain. Yes a 3/4" cap with a 3/16" hole.
 
The Macy's Hurricane fan looks very interesting. For my TR3A, I put the yellow fan in (backwards) about 20 years ago and, because the car lives in Mesa, Arizona, switched to an aluminum radiator and added a thermostatically controlled electric pusher fan mounted above the oil cooler. So, if one is inclined to even consider driving the car out here in the 110 degree summer heat, the car actually does not overheat, unlike me.
 
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