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coolant recovery
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PeterK
Yoda
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My radiator man (old timer) said the depth of the neck and the cap would have to be changed to use coolant recovery, rather than just overflow, on my 4A.
But with the expansion tank on the TR3, it wouldn't be possible because the water level is not high enough at the neck.
Tell me I'm wrong because I would like to do the same to my 3A.
But with the expansion tank on the TR3, it wouldn't be possible because the water level is not high enough at the neck.
Tell me I'm wrong because I would like to do the same to my 3A.
Geo Hahn
Yoda
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On my (late, no-neck) TR4 I added an recovery bottle (as used on Spits & 6s) and it works just fine using the original radiator cap.
On the TR3 the cap does not seal the system in the same way and proper caps are either not available or hard to find (because of deeper size). Some have reported using a gasket from a 'recovery' cap on their stock TR3 cap and it was able to pull recovery... I have not tried this.
Others think this is less necessary on a TR3 (and early TR4) as that long neck holds about a quart and is your expansion tank right there - no recovery needed.
Still others think the whole recovery notion is a bad idea for these radiators as the contraction/pulling that results is a strain they weren't designed for and over time may cause the radiator to fail.
Finally, I have also seen a recovery set-up on a TR3 that located the overflow tank higher than the raditor neck by using a shallow tank located over by the pedal box. The idea is that it is all down hill from there so the cap does not need to be tightly sealed to allow coolant to move back into the radiator.
BTW, when I say the cap needs to be sealed for recovery -- I mena sealed for suction. All caps are (or should be) sealed for pressure).
On the TR3 the cap does not seal the system in the same way and proper caps are either not available or hard to find (because of deeper size). Some have reported using a gasket from a 'recovery' cap on their stock TR3 cap and it was able to pull recovery... I have not tried this.
Others think this is less necessary on a TR3 (and early TR4) as that long neck holds about a quart and is your expansion tank right there - no recovery needed.
Still others think the whole recovery notion is a bad idea for these radiators as the contraction/pulling that results is a strain they weren't designed for and over time may cause the radiator to fail.
Finally, I have also seen a recovery set-up on a TR3 that located the overflow tank higher than the raditor neck by using a shallow tank located over by the pedal box. The idea is that it is all down hill from there so the cap does not need to be tightly sealed to allow coolant to move back into the radiator.
BTW, when I say the cap needs to be sealed for recovery -- I mena sealed for suction. All caps are (or should be) sealed for pressure).
Merlin63Tr4
Jedi Trainee
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I don't know how deep the filler neck of a Tr3 radiator is, but on my 63Tr4 with a "no neck' radiator I'm using the coolant recovery bottle and bracket from a Tr4A and a <span style='font-family: Arial Black'>Stant</span> part number <span style='font-family: Arial Black'>328</span>, <span style='font-family: Arial Black'>7psi</span> "Lev-R-Vent" cap. I think the cap was originally part number SP28, it fit a 3/4 inch deep filler neck the bubble pack the cap comes in has p/n 11328 marked on it. /bcforum/images/%%GRAEMLIN_URL%%/grin.gif
Keoke
Great Pumpkin
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Yep Peter, you got some bum dope regarding the placement of a coolant recovery tank. It is only necessary that either the radiator or the recovery tank be sealed with a pressure cap. If you choose to pressurise the radiator a cap must be secured that has a small bleeder valve inside in addition to the Normal 7 pound seal. The water will rise in the neck of the radiator when heated such that its expansion causes the internal pressure to exceed the radiator cap's pressure rating. Consequently, coolant will be expelled to the overflow tank. As the engine cools the coolant will contract, causing a vacuum to be formed which opens the little valve inside and coaxes the water back into the radiator.---Keoke
Note: in the event a cap is not available for your radiator then purchase an overflow bottle with one . A good source is the one used on the Volvo P1800 cars. Then a non pressurised but sealing cap is only required for the radiator.
Note: in the event a cap is not available for your radiator then purchase an overflow bottle with one . A good source is the one used on the Volvo P1800 cars. Then a non pressurised but sealing cap is only required for the radiator.