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Triumph TR6 - Keeping cool in traffic
When summer time hits the Midwest I'm planning on using my '76 TR6 pretty regularly to commute to the shop and back. I saw the Hayden electric fans in the Moss catalogue and was wondering if anyone on the board has one of those in use on their car. Also, since there are no actual temperature markings on the TEMP gauge, what is the "normal" operating temp that the TR6 engine runs at? I'm trying to figure out how to prevent the car from overheating when the inevitable traffic jam occurs. I'll be flushing the cooling system before I put the car away for winter and will also add Water Wetter but that only helps to some extent. If you sit long enough in traffic, everyone knows that TR6s like to get a little on the warm side. I am basically looking to make it so the car can withstand a good traffic jam and not require me to pull over or turn the heat on. Any suggestions or is this just the way the car is?
An electric fan is the way to go! The fan driven belt works in exactly the opposite way that it should: when at idle the fan is driven slow when it should be fast and at speed when you have lots of airflow you dont really need a fan but its going like hell. I have an electric fan one on a modified engine and it works very well - at long idle on a hot day it will not overheat. An additional benefit is that you will gain a noticable power increase since you are no longer using engine power to drive the fan and your car runs cooler which adds power. There is no down side to this mod. Theoretically I think the operating temperature is determined by the thermostat you choose. I use a 160 degree. You can probably save a bundle if you buy your fan and thermostat from someone other than moss- they are readily available.
If its any help mine runs at approx 1/3 scale under normal driving conditions and climbs to about 1/2 when caught in heavy traffic but we don't get anything like the ambient temperatures that you do so I don't have an electric fan
|My TR3A was always overheating and blowing head gaskets (3 or 4) in its former life (first 80,350 miles) so when I did my restoration from 1987 to 1990, I put on Grade 8 head nuts that I bought from Ken gillanders BFEKENG@aol.com and which are 7/8" high with 14 threads in them instead of the standard ones which measure 1/2" high with only 10 threads. |
In over 78,000 miles since, I've never blown a head gasket. I also put in an electric fan. It keeps things really cool. In less than a minute, it can drop the temp on my gauge from 215 down to 185 F.
But I left in my original hub for the fan as well as the original fan. I like to show the car in concours so I left it in for originality. It seem that this extension cast iron hub for the fan on a TR3A is like the harmonic balancer on a TR6 and I have heard that people who have removed the TR3 hub and fan can quickly break the crankshaft.
Anybody anything to add on this about the TR6 engine ?
Don Elliott, 1958 TR3A
Having built a few street rods (which can have heating issues) I have a few tips to pass along.
First of all, the deal here is to get the coolant to the radiator and let it flow through there so that the coolant is COOLED (or the heat is extracted from it). Removing the thermostat NEGATES this as it allows the coolant to run TOO FAST through the radiator and not enough of the heat is extracted.
A water pump has impellers. If the impellers are corroded or missing a fin then your flow is reduced.
A pressurized system is imperative. Coolant under pressure has a higher boiling point than coolant which is not under pressure.
Air flow through the radiator is critical as we all know. Put the largest fan you can fit on the front of your radiator. I used to run mechanical AND electric on some street rods. The trick here is to run a thermostatic switch that will turn on as you come to temperature. Example being:
The car is running along and the temp is 170 degrees. Everybody is happy under the hood (except the goose). When we reach 175 the thermostaticly controlled fan lights off and starts to cool things (or keep them cool).
The radiator shroud is IMPERATIVE.
Remember: It's easier to KEEP things cool than to cool them once they are hot.
I did a temporary install of an SW gauge in my 6 to see just what it's temperature REALLY is. I run in the middle of the Smiths gauge and that's 180 degrees according to my SW gauge and my candy thermometer (probed into the radiator top with the engine fully warmed).
Whew, I'll shut up now.
Jim (cool but not as cool as my 6)
Thanks all for the help guys. That confirmed my suspicion that the fan is indeed a worthwhile investment. I will be ordering one this winter for next summer's use. My TR6 runs right under the middle mark on the temp gauge in normal operation but when sitting, it slowly creeps up towards boiling. I'll also be adding Water Wetter after the coolant flush.
|I went with a Hayden fan last year after the engine rebuild. It works fine. You'll probably want to get the adjustable thermostat like the one sold by Victoria Brit.|
If you make the fan a "puller" there will not be enough room for it and the old mechanical fan spacer on the harmonic balancer. I ended up cutting it off at the shoulder closest to the balancer, and bought a shorter crank bolt.
|Aaron-You will probably find a lot info on electic fans in the archieves as the subject comes up quite often. The two small dots in the middle of the temp gauge is 180 deg.,which is about where most cars run until the outside temp is 90 deg or you are stuck in heavy traffic. If you want to go to an electric fan, more bang for the buck can be had from one of the hot rod suppliers such as Jegs. In mounting the fan as a puller, I would save the original fan spacer in case you or the next owner wants to use the original fan. It is easy to fabricate a replacement and use a shorter bolt. I try not to do anything that can't be undone. Here is a site with a detailed description of an installation: www.hottr6.com/triumph/tr6fan.html|
Thanks for the link to the article! I didn't realize that buying a fan from a place like Jegs or Summit was that much cheaper than Victoria or Moss! Wow!
One other thing though, everyone seems to have mounted their fans in a "puller" configuration. How about mounting it as a "pusher" on the front side of the radiator?
|The electric fan in my TR3A is in front of the rad as a pusher. I wanted to keep the old fan for originality in TRA & VTR concours competitions. It works very well. But before I bought it (Made in England by Kenlowe while I was over there on business), I made sure that it could work as a pusher. On my fan it's just a matter of connecting it one way or the other with the two wires. It works fine as indicated in my message 6 above.|
Don Elliott, 1958 TR3A
|Well Jim Etc. just about covered it all.|
In all the years I've had my 72, and Tr250 before I never had overheating problems. Good fan shroud and staying away from cheap recoring? Too few and too large passages in rad don't slow and cool the coolant.
Like Jim I play with Rods and have had problems there. Mostly due to room and looks. Pull setups are more efficient than push. Plus the fan is less subjected to wind buffet. Hard on the fan motor at speed.
Find a friendly junkyard. Take a walk with your tape and toolbox remove yourself will save a fortune. Many of the O/E units are ultra slim pulls. Little mounting ingenuity and your set.
Tons of scrapped mini vans etc. with no room under the hood mean ultra slim fans? Around here older ones go for $5.00 you remove. Take all the wire and sensor goodies. Never got a bad one but if they want any more coin jump test from a battery. I prefer smaller kitty corner duals quite common and 1 fan will still get you home.
Hint: any rodder will tell you Chrysler makes realy great small parts cars :)
|Bill&Aaron-You are right on both accounts Bill, the cheapest source for a fan is the "recyclers)", but may require some creativty in mounting. I ended up with a fan from a BMW for about $35, but went back to the stock fan just because simple is better and overheating really wasn't a problem.|
|There you go Aaron. Thanks Berry. Yep Beamer and Benz parts will cost a bit more. But they last forever as per our last comunication right Aaron :) |
And by the way you may be right. I've switched mostly to Bosch for my GM electricals. Seem more reliable. Ouch Ouch Ouch as I eat my words.:)
As to push pull almost all 12 volt DC motors are reversable by swapping leads. Some that have dual speeds have electronics built in won't. Rare and not found on the cheap under 50Gs cars?
Hehe, I was actually thinking of going through my used parts shelf at my shop to see if I had a Bosch electric fan. The ones used on Mercedes are nice and thin so clearance should not be a problem. Although it's definitely worth checking one with a battery at a junk yard (on a Mercedes) because they're a bit time consuming to remove, etc..
I wonder though, if I can find a Kenlowe fan over here in the US?
In addition to the electric fan there are two other mods you can do that will make a huge difference.
1. Recore your radiator with a modern tripple core.
2. Install a high flow water pump impeller.
Those two mods will increase the effectiveness of heat transfer.
My car runs a bit below the first mark at speed and heats up to the middle mark in a traffic jam on a hot day.
73 5 speed.
This thread was discussed between 25/10/2003 and 27/10/2003
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