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radiator: brass/copper vs aluminium/plastic
02GF74 - 6/3/13 at 09:37 PM

Vehicle is Series 3 Land Rover fitted with rover V8; has original 2.3 l brass/copper core radiator that I am looking to replace with a Mitsubishi shogun 2.9 D. From what I can tell, this is an aluminium core with plastic header tanks,

What is the advantage of each? For some reason I have it in my mind that brass/copper are sronger than the plastic/alu - is there any evidence that is so?

inkafone - 6/3/13 at 10:02 PM

Brass/copper will conduct heat better but will be quite a bit heavier. As for being stronger do you mean will take higher pressures - probably not. Plastic/Ali will be much cheaper to make and will lose in a fight with brass/copper - latter polishes up better.

britishtrident - 6/3/13 at 10:08 PM

Brass rads are repairable/modifiable -- not that there are many rad shops left these days.

02GF74 - 7/3/13 at 07:49 AM

weight - don't care about that.

re: strong - how it stands up to being shaken about (it will be in a vehicle driven off road).


conductivity of copper is 2x that of Al (401 vs 201) - I don't think the headers contribute a lot since the majority of heat will be lost via the matrix by convection.

snapper - 7/3/13 at 08:03 AM

Brass/ copper can be fixed in the field by bending a core flat with long nose plyers then soldered when back in the workshop
Ally plastic will need to be thrown away

Paul Turner - 7/3/13 at 08:59 AM

When I built my current Caterham in 1992 I bought the optional alloy rad, my first Caterham had a copper one and never had an issue with it but alloy must be better since its lighter. After 12 months it stated to leak, Caterham said guarantee expired, local radiator man said not repairable. Between us we designed a copper rad using a modern core and chamfered top and bottom tanks, it was heavier empty but full of water it was exactly the same weight as the alloy one, result and 1/2 the price. Perfect for probably 15 years then it started to develop more leaks than a government department, finally got fed up getting one leak fixed for another to start. Allyfab who are local to me had started to do alloy rads and made me a special using a Pace core and chamfered alloy tanks like the copper one. This one is way lighter than anything before and so far no leaks. Good price as well.

Caterham rads now have ally cores and plastic tanks, slightly cheaper than my Allyfab special but they have regular failures.

britishtrident - 7/3/13 at 01:08 PM

A couple of tips to make rads last longer.
(1) Renew the top hose every few years, they harden and can cause fatigue failures particularly at the soldered joint the top hose spigot.
(2) Rubber mount the rad to allow for vibration and thermal expansion.

loggyboy - 7/3/13 at 01:29 PM

I recal reading a thread on here a few years back about the same subject....


...here it is:

http://www.locostbuilders.co.uk/viewthread.php?tid=131549


quote:
Originally posted by Paul Turner
Between us we designed a copper rad using a modern core and chamfered top and bottom tanks, it was heavier empty but full of water it was exactly the same weight as the alloy one, result and 1/2 the price.


Surely that just meant the new rad was likely to be less efficent has it contained/passed less water?!

Paul Turner - 7/3/13 at 01:41 PM

quote:
Originally posted by loggyboy

quote:
Originally posted by Paul Turner
Between us we designed a copper rad using a modern core and chamfered top and bottom tanks, it was heavier empty but full of water it was exactly the same weight as the alloy one, result and 1/2 the price.


Surely that just meant the new rad was likely to be less efficent has it contained/passed less water?!



No it did not make it less efficient. It had the same sized 4 row core that contained and passed exactly the same amount of water. The water in the top and bottom tanks does not help cooling its the water in the cores that cools. All we did was reduce the size of the tanks to make them a sensible size.

All my radiators have been rubber mounted, its certain death to the radiator if you don't especially in a firmly sprung sports car.

acb2713 - 7/3/13 at 03:51 PM

From my limited experience, plastic header tanks will eventually crack, and they are not repairable, meaning a new radiator will be required. Some header tanks are available for replacement, however, their cost, plus the cost of labour involved in replacing the faulty header tank, can be more than a replacement radiator.

Given the choice, I would opt for brass/copper every time.

britishtrident - 7/3/13 at 04:23 PM

I don't if the Landy has enough width but Rover 75/MG ZT rads (all FWD models use the same rad) are cheap as chips new I paid less than 60 quid delivered a couple of years back for one -- loads of cooling capacity core is about 760mm wide + 60mm foir the end tanks.

ROVER 75 1.8 2.0 2.5 MANUAL/AUTO 1999-2005 RADIATOR NEW BOXED | eBay

I noticed there is a seller with 75 V8/MG ZT 260 rads on ebay for £70 delivered.

Rover 75 (99-) 4.6 I V8 Petrol OE-PCC000960 Radiator | eBay