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TR4A_IRS
07-19-2011, 09:43 PM
I have been driving the 4A to work for the last couple of days (lucky me - its not sunny in Seattle, but its not 100F either). Today I hit a bit of stop and go traffic on the way home and was watching the temp guage climb towards the red. Luckily traffic picked up before I had to pull over and let the car cool down.

I guess I have two questions:

1) Is this overheating to be expected? I believe the cooling system is in good working order. Water pump and thermostat seem to be working normally, and the radiator is in good shape. I have experienced similar temperature rise before, in stop and go traffic, and the car has no problems maintaining temp when moving, even when it gets above 60F in Seattle. :whistle:

2) For those that have electric fans, do they do a good job for you in stop and go traffic. I plan to avoid traffic as much as possible, but you can't always do that in Seattle. I am considering adding an electric fan with a manual switch, if it has helped others in traffic.

TR3driver
07-19-2011, 10:36 PM
Your description seems a bit much to me, indicating something may be less than perfect in the cooling system. With the TR3 and a stock radiator fan, it would get warmer in stop and go traffic; but the only time it got close to boiling, I spent close to an hour in traffic and temps were around 85-90F.

My electric fan (as a replacement for the stock fan) worked great on the 3A. I could flip it on, and the temp gauge would start dropping almost visibly (you could see it if you looked at it steadily). It wouldn't overheat, even in heavy traffic and 115F heat (although the driver overheated :smile: )

But it's definitely not a cure-all. The 3A proved to have a problem with the radiator tubes not being in good thermal contact with the fins : Nothing seemed to help with overheating until I had the radiator re-cored. And the TR3 is going back to the radiator shop soon, likely for the same thing after they do some tests.

If you can, I would definitely suggest an automatic control. I am forever forgetting to turn it off, or worse yet turn it on. DeRale makes a nice adjustable control, with an integral relay and a probe that just pushes into the radiator fins:
https://www.amazon.com/Derale-16759-Adjustable-Fan-Controller/dp/B000CN4XZI

DNK
07-19-2011, 10:37 PM
Seattle temp at that time today . Probably 62 and not a bit of sun

Darrell_Walker
07-19-2011, 10:41 PM
Hi Ian,

I used to live in a much hotter place (Bakersfield, CA), had the mechanical fan, and never had any overheating issues. Then about 10 years ago I did a total rebuild on the engine, and since then I was always on the edge of overheating if the car wasn't moving. I never could find any reason for it.

I now have a thermostatically controlled electric fan (and an aluminum radiator, but that was more for the bling), and everything works well. I do recommend getting the largest fan you can fit. My first attempt was a 12" fan, and it just wasn't up to the job. I replaced it with a 14" Permacool fan (who are now out of business, I think). Aside from the larger size, it seemed to be a much more powerful fan, and things were much better.

I now have a 16" fan on my aluminum radiator.

-Darrell

Darrell_Walker
07-19-2011, 10:44 PM
Another thing I did with my new fan was to wire it to be on regardless of the ignition. So it really helps to cool down the engine compartment after shutting the car down. Both Volkswagens that I've owned (76 Rabbit and 09 Tiguan) are set up this way, (and I think my MR2 was as well, though that was a different fan in the engine compartment, not the radiator fan).

TR4A_IRS
07-19-2011, 10:50 PM
Randall,

I appreciate your point about the electric fans not being a cure all. I want to make sure everything in the cooling system is up to snuff, before adding an electric fan.

Since I was in stop and go traffic for about half an hour, I had the chance to observe the bahavior quite well. If the car was stopped, or nearly so, the temperature would creep up slowly after about five minutes. I never got there, but I think I would have been in the red after about ten minutes of being stopped. As soon as I was able to make decent forward progress, say 15mph, the temperature would stabilize and start to drop back towards the middle of the guage.

Since minimal airflow could cool the car, it made me wonder if this was just typical behavior for a car that is older than I am.

On a related note, I think the radiator is original. I had a leak repaired about 15 years ago, but haven't done anything else to it since I bought the car.

TR4A_IRS
07-19-2011, 10:54 PM
Darrell,

Thanks for the suggestions. I think I am going to look at my different options for the radiator. I think I have four:

1) Do nothing. The car is usually fine, since I don't sit in traffic often.
2) Recore.
3) Replacement stock-type radiator. (I am wary of quality)
4) AL replacement.

Window shopping is fun. Spending money, less so!

DNK
07-19-2011, 11:03 PM
Ian, not a lot of places in our area for a recore. Performance Rad is about it.
140th and 99.
They do the work in Tacoma.
Company does all my work . Fuel tank too.

Darrell_Walker
07-19-2011, 11:21 PM
Darrell,

Thanks for the suggestions. I think I am going to look at my different options for the radiator. I think I have four:

1) Do nothing. The car is usually fine, since I don't sit in traffic often.
2) Recore.
3) Replacement stock-type radiator. (I am wary of quality)
4) AL replacement.

Window shopping is fun. Spending money, less so!

Hi Ian,

I'd add a good flush to the list as the first option. Refill with 50/50 water/anti-freeze, and maybe water wetter.

I do have my old stock radiator, which was re-cored about 10 years ago, and as far as I know is in good functional shape (the upper and lower tanks are a bit banged up). PM me if you might be interested.

-Darrell

TR4A_IRS
07-19-2011, 11:42 PM
Ian, not a lot of places in our area for a recore. Performance Rad is about it.
140th and 99.
They do the work in Tacoma.
Company does all my work . Fuel tank too.

Thanks. There WAS a radiator shop in N. Seattle, on Aurora, a few years back. Don't recall the name, but they did the brazing on my curent radiator.

TR3driver
07-19-2011, 11:43 PM
Any radiator shop should be able to handle the re-core, there's nothing magical about it. The core mine put in was a standard Modine core, and fit perfectly in the original frame. I opted to not have the crank hole installed, but they would have done it if I had chosen that way. My radiator guy said it would cut cooling capacity by about 10% and I didn't even own a crank at the time, so the choice was obvious.

Obviously you know the area better than I do, but Seattle Radiator Works looks like a good choice : https://seattleradiator.net/
So does Young Radiator (tho they don't seem to have a web site).

TR4A_IRS
07-19-2011, 11:45 PM
Darrell,

Thanks for the suggestions. I think I am going to look at my different options for the radiator. I think I have four:

1) Do nothing. The car is usually fine, since I don't sit in traffic often.
2) Recore.
3) Replacement stock-type radiator. (I am wary of quality)
4) AL replacement.

Window shopping is fun. Spending money, less so!

Hi Ian,

I'd add a good flush to the list as the first option. Refill with 50/50 water/anti-freeze, and maybe water wetter.

I do have my old stock radiator, which was re-cored about 10 years ago, and as far as I know is in good functional shape (the upper and lower tanks are a bit banged up). PM me if you might be interested.

-Darrell

Darrell,

The cooling system, was recently flushed, and has a 50/50 mix in there now. I am doubtful it is crudded up. I will keep your radiator in mind as I work through my options. Thanks!

Darrell_Walker
07-19-2011, 11:52 PM
Darrell,

The cooling system, was recently flushed, and has a 50/50 mix in there now. I am doubtful it is crudded up. I will keep your radiator in mind as I work through my options. Thanks!



OK. Did you also drain the block? If you remove the drain tap, you can use a wire to root around in there a bit. That probably won't make the difference, but something to check next time you change coolant.

You might already know this, but if you get in that situation again you turn the heat on (and the heater fan) to get a little extra cooling. Won't make a huge difference, but it could be the difference from needing to pull over or making a few more minutes until the traffic moves again.

TR4A_IRS
07-20-2011, 12:08 AM
You might already know this, but if you get in that situation again you turn the heat on (and the heater fan) to get a little extra cooling. Won't make a huge difference, but it could be the difference from needing to pull over or making a few more minutes until the traffic moves again.

Its funny you should mention that. I was thinking of that today, but realized that I couldn't do it without stopping the car. My heater valve (I think they all work this way) can be manually rotated to a "closed" position, that makes it nearly impossible to open with the knob. I usually close it off in the summer, and "re-open" it in the fall so I can have heat again. It was closed today...

TR4A_IRS
07-20-2011, 12:10 AM
Double post...

Darrell_Walker
07-20-2011, 12:12 AM
Its funny you should mention that. I was thinking of that today, but realized that I couldn't do it without stopping the car. My heater valve (I think they all work this way) can be manually rotated to a "closed" position, that makes it nearly impossible to open with the knob. I usually close it off in the summer, and "re-open" it in the fall so I can have heat again. It was closed today...

Mine works that way, too.

World Wide Auto Parts (I think) is supposed to be able to rework them to work more smoothly, I'm waiting for Brosky to post his results. Only costs $15, I think.

JerryVV
07-20-2011, 05:50 AM
Richard Good (Goodparts) now makes a beautiful and very functional radiator shroud for the TR4A. If you don't use a shroud or have that poor excuse for a replacement shroud, you might consider his item If it's not on his web site write to him. I was his trial bed for developement and got one of the first production pieces that he made. Good stuff from a Good guy. NFI

TR4A_IRS
07-20-2011, 09:43 AM
Jerry,

My shroud is cardboard, and is starting to sag, as they all do, but it is in pretty good shape. I didn't know GoodParts made a shroud for the TR4A. Thanks for the info. I'll keep it in mind if/when I replace the cardboard one.

Rrbbeerrttoo
07-23-2011, 06:10 PM
The radiator shrouds I bought never fitted well so I made my own. It was simple. From light gauge cardboard I made a mock-up first, then copied the idea and dimensions into heavy duty double cardboard ( back to back pieces ). Then used glue and rust proof stapling/rivets, on both pieces , after shaping the finished shroud. I also applied undercoating/tar all over; a must for the wet NW. Others may have better ideas...Or, if lucky, the $ 40 Moss shroud will fit your car.
Robert

Rrbbeerrttoo
07-23-2011, 06:15 PM
Forgot to mention, my 12 in. cooling fan hardly blows any air when car is standing still ( the purpose of this fan installation ). Do not know what is does when car is moving, although unscientific, I do not notice much difference!

poolboy
07-23-2011, 08:04 PM
A 12 inch fan doesn't move much air..that's a fact.

martx-5
07-24-2011, 10:16 AM
A 12 inch fan doesn't move much air..that's a fact.

It all depends on the fan that you get. Many 12" fans only move about 800 cfm. The one I'm using moves 1630 cfm.

Jim_Stevens
07-25-2011, 05:56 PM
My 3a had the same problem, but here in Virginia. I have 86-mm pistons, though. Fixed it with an aluminum radiator and electric fan. Cleaning just didn;t work for me. Jim

djwoody
07-28-2011, 03:52 PM
My gauge also climbs very close to the red zone in heavy traffic on hot days. Here in Toronto we have had temperatures in the low 90's several time this summer. Add to that high humidity and I find myself driving with one eye on the road and the other on the temp gauge. It's exactly what you describe - start moving and after a couple of minutes the temp drops to a "comfortable" level but hit traffic again and it instantly climbs back up again.

My radiator was re-cored about 3 years ago and I did a complete flush & fill before storing the car last winter. I have an electric fan (in front - pushing air) but it doesn't seem to do much either - I think it's a 12" unit but only kicks in when the temp gets very high. I can't turn on the heater because my blower motor is not functioning.

I've taken to driving around with a gallon jug of water in my trunk just in case but wish I could find a way to get that fan to be more effective. Maybe it's just an inaccurate temp gauge??? I've also wondered if replacing the thermostat might help.

TFB
07-28-2011, 04:52 PM
Dion,what happens when fan comes on?If motor temp drops you may be able to just improve fan control with different(lower) range sensor,adjustable control,or manual overide.
Also,what do you do with the jug of water,pour it on the radiator?
Have fun Tom

TR3driver
07-28-2011, 05:09 PM
One simple test for temp gauge accuracy (and whether the thermostat is working) is to start the engine and let it run at a fast idle with the hood up. Feel the top of the radiator from time to time as the gauge starts to climb. It should stay relatively cool until the moment the thermostat opens. When it suddenly gets hot, the temp gauge reading should match the thermostat rating.

My TR3A worked very well with just an 800 cfm 12" electric puller fan and no mechanical fan. Had 87mm liners for about 2.2L displacement, and a Modine radiator core with no crank hole. Didn't need the fan at all above about 45 mph, and it would keep the motor cool even in 115F heat and stop-and-go traffic.

However, the same setup is not working so well in my TR3, so it's not always about the fan & radiator.

DeRale makes a nice adjustable fan controller, with a control probe that just pushes into the fins of the radiator. It also has an input for an override switch if you are so inclined. Seems like that might be a good first step for your problem, Dion.

It also might be worth having a look at the water pump impellor. Although not a common problem, they do sometimes manage to erode away until the pump just doesn't move enough water at low engine rpm.

Geo Hahn
07-28-2011, 06:21 PM
...look at the water pump impellor... they do sometimes manage to erode away until the pump just doesn't move enough water at low engine rpm.

And there was a time when some aftermarket pumps were supplied with much shallower impellers than original.

MarshgrassA
07-29-2011, 09:12 AM
Ian,
So far my only overheating issues are with the driver not the car! My 67 TR4A seems to do much better than me in this heat with the stock stuff. I do have the extra electric fan on my MGA but since it came with that I can't compare the before but it does help in stop and go traffic.
Hopefully cooler weather is coming in a month or so.......

Cheers,
Irene

DanB
07-29-2011, 10:19 AM
I put a TR6 fan on mine, the one with 7 blades I think, and it has helped. No electric fan yet.

Dan B

TR3TomG
08-01-2011, 01:01 PM
I also had questions about the accurancy of my temp gauge. Picked up a cheap infared temp gauge on Ebay (about $10) and used it to check. Well worth the money, condsidering that it really worked.

Regarding replacement of the thermostat - I put in a sleved model from Moss (about $100) and it didnt seem to make a difference. The gauage inticates about 185 degrees almost all the time, except on hot days in traffic or stopped at a light when it will then climb a bit. I am thinking of putting an electric fan in front of the radiator with a manual switch. I am very reluctant to do much more. Any thoughts or other suggestons?

martx-5
08-01-2011, 02:33 PM
...The gauage inticates about 185 degrees almost all the time, except on hot days in traffic or stopped at a light when it will then climb a bit. I am thinking of putting an electric fan in front of the radiator with a manual switch. I am very reluctant to do much more. Any thoughts or other suggestons?

If it ain't broke, don't fix it. If it's running 185 most of the time, then everything in the cooling system appears to be working properly. Even in the best of shape, the cooling system in the TR3's is just about adequate. Putting in an electric fan for those times when it really get's hot and your stuck in traffic is a good idea and will help you keep your cool also without having to worry about the engine temp creeping up.

Geo Hahn
08-01-2011, 04:03 PM
...I am thinking of putting an electric fan in front of the radiator with a manual switch. I am very reluctant to do much more. Any thoughts or other suggestons?

I added the aux electric fan w/ manual switch and find it helpful in slow traffic. The rest of the system was stock (crank hole still in place) until I switched to a tropical fan. In my seat-of-the-pants judgement that made a big difference. My driving often invloves going up a mountain inhot weather where traffic can hold my speed down to 30 mph or so -- that tropical fan seems to keep the engine decidely cooler than the stock fan used to.

TR3TomG
08-01-2011, 04:37 PM
I have done a bit of research, and the name Hayden for the brand of fan most used seems to keep coming up. Apparantly, that is the brand that Moss sells.

If anyone has any thoughts on a fan brand (and size) that might be best for my TR3, Id appreciate your advice on this. I intend to use this as a "pusher" (i.e., in front of the radiator). Also, is a 12 inch fan the way to go, or will a 14 inch fan fit / work best?

Many thanks for the advice!

MichaelG
08-02-2011, 10:37 AM
Do you have the stock fan on the car? As someone else mentioned, I also installed the yellow 6-7 blade plastic TR 6 fan on my 4A and found it to be very effective..assuming of course that the rest of the system checks out OK.

Geo Hahn
08-02-2011, 01:16 PM
...If anyone has any thoughts on a fan brand (and size) that might be best for my TR3, Id appreciate your advice on this. I intend to use this as a "pusher" (i.e., in front of the radiator). Also, is a 12 inch fan the way to go, or will a 14 inch fan fit / work best?

I use a 12" as a pusher -- it is just an inexpensive one from the FLAPS but had the same CFM claim as the Hayden and came with a lifetime warranty.

https://members.cybertrails.com/~ahwahnee/fan.JPG

I think a 14" would be wider than the radiator.