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Tips

TR2/3/3A Cooling system normal?

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HighAltitudeTR3

HighAltitudeTR3

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My 59 TR3 will blow coolant out of the overflow valve every time I refil it. I don't think I'm over filling it, but it's also hard to tell if I was able to drain the entire system. im also concerned there are air bubbles in the lines... any advice on how to fill, or refill, check level, and/or make sure that I do not have air in the lines?

I also do have the heater...

Thanks!!
 
You're probably overfilling it. There has to be some room for expansion. Also, be sure the radiator cap is right--they come with various relief pressures. Not sure what the TR3 one should be set for, but it will be listed in the shop manual. Shop manual gives 4 psi for the TR4; I assume the TR3 is the same.

Your altitude may also be a factor. At 7000 ft, atmospheric pressure is about 2 psi lower than sea level, and I think Aspen is around 8000, yes? You might need a little higher pressure cap (maybe 6 or 7 psi?) to compensate, but be careful of too much pressure if you visit the flatlands.

If you open both the block and radiator taps, open the heater valve, and remove the radiator cap, you should be able to drain the system just fine. Flush it with water and a radiator-flush substance from your local parts store, following the instructions on the bottle. Then close the taps, keep the heater valve open, refill with coolant, run the car a bit, and recheck the levels. You shouldn't have problems with air bubbles. None of this is the proverbial rocket science.
 
I put a radiator overflow bottle on my 1961 TR3 and every time I drive it I get some fluid in the bottle, although a very small amount. Note that the TR3 radiator will not pull the liquid out for the bottle back into the radiator.
Bob
 
Thanks for the tips. I had a feeling I was over filling it. Although I don't see any fluid in the reservoir. When I go for a drive I get steam from the overflow tube for a few mins after I shut off the engine. Doesn't seem bad, just doesn't seem like I am getting fluid everywhere in the system.

I'll try what you mentioned and see what that produces. I am running a 7lb cap, which I believe is just fine.

I might try and add a small over flow container just to avoid some of the onlookers concerns. :smile:
 
Are you sure that you have the right cap?? The original cap fits a 1" depth radiator, whereas most caps available today fit a 3/4" depth radiator. A 3/4" depth cap will not seat properly on a radiator that requires the deeper cap.
 
Just measured. Definitely have 3/4 (or less:/)

Since I am getting a new one should I get 4lb or 7lb?
 
As the system is set up for 4 lb., I would continue using that. I lived in Durango for many years and drove a TR3 throughout Colorado with the lower pressure cap with no problems.
Charley
 
You definitely need the correct cap - you may find you will need to get it from one of the usual vendors as that long reach is somewhat uncommon in the world of radiator caps.

A 4 lbs cap should be best - does the job w/o additional strain on the radiator & heater core. In the summer I live at 7000' but I also drive in desert heat - if the rest of the system is working well then the stock cap is fine.
 
I am debating getting the one from Victoria British. Seems odd it's only $3. Anyone order one with luck from VB?
 
I suspect that you are going to pay a lot more than $3 when shipping is added on. Compare the total cost from the other sources. For myself I do not get parts from VB.
The old saying is-You get what you pay for. In this case you are hoping to get more than you pay for.
Charley
 
You should fill the rad so you can see 1/4" to 3/8" depth of coolant as you look down the fill hole. More than this and the excess will just blow down the overflow hose.

When you fill the system, leave the cap off till the engine gets warmed up and re-check the level. If you have an air block or a vapour block the level will drop and you will need to top it up. Make sure the heater valve is open too. Then put a 4 pound cap on securely.

Don Elliott, Original Owner 1958 TR3A
 
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