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TR2/3/3A Ultimate fan conversion

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mctriumph

mctriumph

Jedi Knight
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For many years I have been converting ALL the tr3's(and 4's) I have worked on to Tr7 fan blades.
No car done this way ever gets hot in traffic on 100deg days.
The old paddles are cut off ,the hub is flattened ,drilled and bolted up .
NO clearance issues,13 blades pull a small hurricane of air through the rad.
Lighter and better.Pulls more air than the 250 fix and is still a factory part!
Mad dog
 

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I have been running the yellow TR6 fan reversed and it seems to work well but a slight clearance issue with the crossbar. I might try your TR7 fan conversion. My stock 4 blade fan is missing those four rubber grommets but maybe the TR6 grommets will work? Do you know if they are the same? Karl
 
Details?? Are you offering a kit or doing conversion $$ervices? Sweaty Texans (who are paranoid about switching on the electric fan but have already had to use it in 2024, yes it's only February) want to know!
 
What I like about this is the Tr7 fan it is cheap and available .It fits perfectly.Does'nt take a lot of beer.
Karl I will mail you the grommets If necessary.The 6 fan likes this too but is less efficient(smaller).
Haydon, the work is NOT the fan, it is pulling off the apron and radiator.Sound like you could use the
up rated water pump Moss sells too. If you are meticulous, it will take 2 hours to convert the blade assy.
Come to the boot sale. April 6th Topeka. Beer and brauts provided. Bring your bits we will do a demo.
Mad dog
 
Why not go with an electric fan conversion? That way you are not having to spin that fan all the time - even in cold weather when you don't need it?

Joel
 
Joel Lester said:
Why not go with an electric fan conversion? That way you are not having to spin that fan all the time - even in cold weather when you don't need it?

Joel
Click to expand...
Too many modifications to mount an electric fan behind the rad and electric fan blocks the airflow in front of the rad.
 
Any body that comes up with a CHEAPER fix , that WORKS , and is BULLET proof is a genius,
(to say the least). Last time I bought Tr7 fans I got 3 for 50$ plus freight.I have gotten them for FREE.
(threw the rest of the car away). If you are doing a tr3 radiator ,this is the trick(IMHO).Did my first one
back in 91.
Mad dog
 
mctriumph said:
Any body that comes up with a CHEAPER fix , that WORKS , and is BULLET proof is a genius,
(to say the least). Last time I bought Tr7 fans I got 3 for 50$ plus freight.I have gotten them for FREE.
(threw the rest of the car away). If you are doing a tr3 radiator ,this is the trick(IMHO).Did my first one
back in 91.
Mad dog
Click to expand...
You mentioned doing or redoing a tr3 radiator….I had my radiator re-cored a couple years back and switched the fan to the reversed yellow Tr6 fan. I got the shop to increase the number of tubes in the rad. I have 3 rows of 28 tubes and no hole for the crank. That’s almost double the number of tubes that is on an original radiator. The temperature stays at 185 and has never been over 190 in start and stop traffic. I actually removed the electric fan this past winter (I haven’t used it since rad job) while fixing the front grill. Figured even better air flow. I did the same on a Midget radiator in the early 90’s and a TR6 about 20 years ago.
Same results with no overheating.
If the top and bottom tubs on the rad are in good shape, it’s slightly cheaper for the re-core with all those extra tubes then what a new rad is worth. Thought I would pass this along. Happy trails!!
 
I had a radiator re-cored recently(as you described) 600$ plus tax. They all have 3 rows, that IS
the blessing AND the curse. If you can get air to flow through the matrix of tubes/fins it works.
This takes a fan that MOVES air, not stirs it a bit. In my humble opinion ,turning a fan blade backwards to get
it to fit is silly. I am merely suggesting what I have found to be the cheapest,most effective way to move
said air. The new alloy radiators are now under 200$ .These may prove to be superior over time(new discussion).
Even then I would still install this Tr7 unit. Then you could try to deicide whether to use a 185 or 195 thermostat...
Mad dog
 
Mad Dog, a detailed description of this mod would be greatly appreciated. I'm currently running no mechanical fan, just an electric fan in a puller configuration. Going back to the mechanical fan has appeal due to its simplicity.
 
I mentioned the TR7 fan conversion to my sister as she checks in on my progress and a few weeks later a box shows up on the front porch. I was not expecting a package but to my surprise a TR7 fan and it looks to be almost new condition. It has been bolted to a motor but shows no sign of wear. She scored it for $25 at a local used parts yard. I am a long way off from needing it but as parts come available I grab them as I know I will eventually need them. Mad Dog, Did you make the adapter plate from scratch or is it the center of a TR3 fan with the blades removed? Frank
 
Frank, you simply hacksaw off the blades from the fan. Then put the stumps in a vise
and take out the twist on each one with the big pliers. Dress the edges and center up the
fan.Drill the holes and bolt it on with good hardware. Plastic is light enough that you only have
to get it close, so no balance issues.
Mad dog
 

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I see that the TR7 fan is NLA from Moss, which means sourcing a used one. And I do have the 8-blade yellow TR250/6 fan in the basement plus a TR3 short fan hub so I can install it frontways (not backwards) - still running original fan for last 24 years.

BUT, my question for years has been whether a 13-blade TR6 red fan moves more air than the 8-blade yellow. Not to mention it looks nearly identical to the TR7 13-blade yellow fan in pictures above. I believe all that would be needed to install it on a TR4/TR4A would be adapter #16 in the diagram below:

1716572342466.png


Not cheap as you're looking at $190 b/t the actual fan and the adapter

Bob
 
Bob the bolt pattern is narrower and is difficult to adapt , fabing up a #16 style plate might work.
I will do some R&D as I have these bits somewhere.
Mad dog
 
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