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TR2/3/3A Overheating Problem

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A lower temp thermostat may buy you a little more time before the engine gets however hot it is going to get but it will not cure overheating.

IOW - it might take 3 stoplights instead of just 2 to create whatever problem is there.

The thermostat merely sets the minimum operating temperature for the engine - once it is open the maximum temp is determined by all the other factors (ambient air temp, driving conditions, radiator, fan, coolant passages, water pump, etc.).

[Oh, and for the amusement of all on these kind of threads -- pressing the Alt key and entering 0176 will usually get you one of these: ° ]
 
carpecursusII said:
David: Nothing will fit in front of the radiator. You can do a few things, run the TR tropical fan (if you can find one), but a yellow fan and mount it backwards to fit, run a TR6 red fan, install a puller electric fan and delete the TR3 fan all together.
Click to expand...

Looking at my Yellow fan it appears as though it is orientated correctly for the engine rotation. Were there some yellow fans that were meant to rotate Counter Clock wise?

Yellow Fan.jpg

David
 
Mounting a fan backwards does not change the direction the air moves - it's like a nut will thread on a bolt no matter which side of the nut you use.

The reversing of the fan is sometimes needed for clearance -- sometimes spacers are also used. Seems to vary from car-to-car even in the same models. A friend's TR4 was able to use the fan normally, I had to flip it and use a spacer for my TR4.

Do you now have the engine pictured installed in a car? The fouling (if it occurs) is typically that the fan is too close to the cross-member.
 
I also have the yellow fan, mounted backwards -and it's still very close to the cross member. Attached is a picture of how two long flat bars were bent to support my electric pusher fan (holes were drilled into the inner fenders). You can also see the temperature probe used to control the fan, and the overflow bottle. On our last west coast trip, we stopped for the day in El Paso, before continuing on thru Tuscon stopping for another day in Los Angeles. We waited until the sun went down and temperatures dropped below 100. Unfortunately, the highway department also waited to repave I-10 until it 'cooled off'. The TR3 never overheated and the stop-n-go traffic allowed us to listen to music for a short period of time.

My TR3 can handle more heat than I can. Living in Houston, it's been tested several times.
 

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DavidApp said:
Would the 160* thermostat be a help in the hotter areas of the US like Georgia?

David
Click to expand...
I have used a 160* thermostat for several years. Works good in the summer--but come the cooler days and the car runs below temperature that is recommended. Which I understand is 185*. I am now back to the 185*.
Charley
 
The engine pictured is sitting on a test stand at the moment so I did not realize that there was a clearance problem with the cross member. 2 seconds thinking about it and I would have realized that it works the same either way round.

I will find out about the clearance in a few months when I get around to that part of the build.
Body work is taking up all my days at the moment. The PO has left me a lot to work with.

David
 
I bought an electric fan with the intent on mounting it as a pusher a few weeks before the Macy's fan was available. I emailed Mark Macy right before I bought the Macy fan and he told me I wouldn't need to mount the electric one - so far, he's right.
 
When I had that fan I ran it with a generator.

I don't recall the numbers but I did measure the draw and decided if I didn't turn on the fan, listen to the radio, use the headlamps, run the wipers and honk the horn all at the same time -- I would probably be okay.
 
Geo Hahn said:
When I had that fan I ran it with a generator.

I don't recall the numbers but I did measure the draw and decided if I didn't turn on the fan, listen to the radio, use the headlamps, run the wipers and honk the horn all at the same time -- I would probably be okay.
Click to expand...
Good one.
 
Just as a matter of interest I've heard that the red fan from a BMW 2002 will work on the TR3. The four mounting bolts line up but you may have to enlarge the holes a bit.
 
Geo Hahn said:
When I had that fan I ran it with a generator.
Click to expand...

Looks like that fan is readily available from Advance for about 65 bucks. Since you were able to install it without removing the apron it's certainly worth giving it a test. Since it looks like there might be some blockage of air flow with the fan off, were you able to notice any change in the cooling efficiency when you were not in stop and go city traffic?
 
RC64 said:
...it looks like there might be some blockage of air flow with the fan off, were you able to notice any change in the cooling efficiency when you were not in stop and go city traffic?
Click to expand...

I can't say I noticed it but I always assumed it was there. You can't put something in front of the radiator (even something will lots of holes in it) without losing some air flow and cooling capacity.

That loss was one reason I finally went with a stronger (Tropical) fan and ditched the electric.

I have also heard about that BMW fan - certainly a strange looking device:

$_1.JPG
 
Hi Folks,

I've had similar overheating problems in slow or non moving traffic. I'm running a 185 Thermostat & probably will install a 165 for Summer use. I also bought Mark Macy's fan & mounting kit but have'nt mounted it yet. I really don't want to remove the apron to do this! Is it "ABSOLUTELY NECESSARY" to remove the apron to mount Marks fan? I currently have a 12" Elec fan mounted on the front of the Rad. In a pushing mode & does help bring the temp down. Any & All input (Again) will be greatly appreciated relative to the front apron removal or not.

Thanx, Russ
 
toysrrus said:
Hi Folks,

I've had similar overheating problems in slow or non moving traffic. I'm running a 185 Thermostat & probably will install a 165 for Summer use. I also bought Mark Macy's fan & mounting kit but have'nt mounted it yet. I really don't want to remove the apron to do this! Is it "ABSOLUTELY NECESSARY" to remove the apron to mount Marks fan? I currently have a 12" Elec fan mounted on the front of the Rad. In a pushing mode & does help bring the temp down. Any & All input (Again) will be greatly appreciated relative to the front apron removal or not.

Thanx, Russ
Click to expand...

have you done all the usual mods?:
new water pump
rodded out or replaced your rad.
plugged the bypass
flushed the engine
adj. Valves & timing.

since you already have the electric pusher....Which probably moves a lot of air, do you think an improved crank fan would help much?
 
I have seen several mentions of plugging or partially plugging the bypass. Is plugging completely better than restricting the flow?

David
 
DavidApp said:
I have seen several mentions of plugging or partially plugging the bypass. Is plugging completely better than restricting the flow?

David
Click to expand...

i think Geo uses a partial plug.

i use a bellows thermstat, which seems to work well, & the way the bypass was designed to work:
but it was gouge at about $100. From TRF.
(Caught me at a weak moment)
 
toysrrus said:
...Is it "ABSOLUTELY NECESSARY" to remove the apron to mount Marks fan?
Click to expand...

You may not know until you try. I was able to remove the TR3A stock fan and replace it with the tropical fan with everything else in place - tight but doable.

The car was on a lift which as helpful as best access is from below.

SS100_1691crop.jpg


The difficulty with Mark's fan may be that thicker profile - could leave you with too little room to get to the mounting bolts with the radiator in place. It might be possible to undo the bottom radiator mounts (another PITA) to shift it forward and gain space -- but really, at that point it start to sound simpler to just remove the apron.

I postponed the apron removal for 30 years until I had no choice - in the end it was much easier than I had imagined.
 
DavidApp said:
I have seen several mentions of plugging or partially plugging the bypass. Is plugging completely better than restricting the flow?
Click to expand...

For a great many years I plugged the hose with a piece of broomstick -- totally blocked the flow and worked fine.

Now I have it blocked with a copper pipe cap with a 3/16" hole - looks more professional than the broomstick and it is probably prudent to allow some flow so the head doesn't get a shock when the thermostat opens.

bypasshose_zpsc06926c1.jpg
 
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