New radiator - which one to choose?

[Speedytriple3503]

Hi All
Am beginning to draw up a (growing!) list of jobs to do before putting my Stag back on the road in the Spring.
The existing, standard radiator has a small leak at the base of the filler tower but appears to be otherwise sound, does not look too old and I am sure would be repairable.
I tried the old trick of some radweld but this was ineffective.The car did not overheat last Summer but I am wondering if replacing the stock one with either a 4 core or supergill is actually worthwhile?
Opinions seem to vary widely on these - when I was at Faversham Classics recently they commented that the supergill radiator actually may run hotter and I have also heard that a 4 core does not make for efficient cooling.
The rest of the cooling systen is also standard.
I'd be grateful for some "real world" advice on this.
Thanks
Mike

[4x4]

The advice I received when I had radiator problems, was that if you have a rad which you know your car does not overheat with, stick with it.
So, I got mine repaired by Serck in Oxford (though they have a number of other branches around).
It was completely overhauled (first thing they do is soak it in a tub of caustic soda to clean everything out), and came back looking like new.
Can't remember exactly what it cost, but it was around £100 - far less than any possible replacement.

Hope this helps.


Adrian.

[Paul Goldsmith]

As a minimum, I'd get the small leak professionally brazed up and subsequently pressure tested as a minimum, as the high pressures in the Stag system will always find any weak points otherwise. Then once the rad is out, it makes sense to check the core out, any respectable company will do this as part of their service (to sell you !).

In the mid 1990's the SOC ran some comparative tests which suggested that the 4-row 'staggered' 'fin & tube' construction provided the best cooling and indeed this was apparently the standard Stag spec until about IIRC 1976 when they opted for a 3-row of the same.

Similar to Adrian, I had our radiator recored by our local Serck depot for around £100 (several years now) and it made a huge difference to our cooling.

Previously we had 4-row of 'packed' construction which upon removal wasn't crudded up, so I can only assume that whilst this is the preferred construction for most modern radiators that it isn't suited to the Stag's low airflow (or it's just the cheaper option so gets used now to save £££'s and suits modern cars)

Fin & tube construction : http://www.gm-radiator.com/test_site...faq&v=ftc#half

Packed construction : http://www.gm-radiator.com/test_site...=faq&v=pc#half

I cannot comment on the Supergill as I've no experience but but I've heard that the 'ultimate' option is a custom aluminium radiator (ie. costly) which several suppliers now offer (eg. EJ Ward and possibly Faversham) but as you've not got cooling issues, then that seems an necessary expense IMO - and even then, I would consider improving the efficiency of the standard setup first

a) Fitting a cowl to the radiator can significantly improve cooling fan efficiency (SOC test +25% using the Triumph 'Tropical kit') but a certain Mercedes cowl (£10ish from a scrappy) can be tweaked to fit instead (http://www.stag.org.uk/forum/showthr...=mercedes+cowl).

b) There's a high level header tank option, VMAD offers a comprehensive kit - several have fitted this successfully and report good results. with more consistent temps. Other options include custom fitting a Mercedes (or Ford) header tank (from a scrappy). There are loads of posts on all options on this forum

c) Check the efficiency of your viscous coupling, if it's worn the mechanical fan won't spin as fast and might 'slip' at lower speeds than intended (it's designed to slip to allow for a maxmise fan speed)

Always a prudent measure before refurbing or replacing your radiator is to add a good flushing compound to clear out any accumulated crud and follow the instructions on whatever product you use. Followed by a thorough reverse flush of the whole cooling system, with radiator & thermostat removed. To go the whole hog, remove the core plugs too and use some wire to fish out any crud behind them. Quality anti-freeze, at concentration of 30% to 50%, the lower % aids cooling but obviously increases risk of freezing if used in severe temperatures. Consider spending £7 or so on a barrel of distilled water, particularly if you live in a hard water area, to minimise future scale build up.

Again lots of instructions already posted on the forum for the above procedure, which is really a bi-annual maintenance task on a Stag and ours is now due but some choose to this annually.

BTW : Whatever Kevin at Faversham has suggested to you, I'd personally seriously consider - they do all our servicing and IMO he's a one of the valued Stag 'gurus'

[ChasR]

Whilst we are on this topic I figure I may as ask about the viscous fan coupling.

How can you tell if the coupling is worn? Does the fan spin at the same rate when hot and cold etc.? Mine seems to be ok but when the Kenlowe fan is operated it can at times actually turn the mechanical fan, albeit very slowly...

[mike@thenook]

Hi All
Am beginning to draw up a (growing!) list of jobs to do before putting my Stag back on the road in the Spring.
The existing, standard radiator has a small leak at the base of the filler tower but appears to be otherwise sound, does not look too old and I am sure would be repairable.
I tried the old trick of some radweld but this was ineffective.The car did not overheat last Summer but I am wondering if replacing the stock one with either a 4 core or supergill is actually worthwhile?
Opinions seem to vary widely on these - when I was at Faversham Classics recently they commented that the supergill radiator actually may run hotter and I have also heard that a 4 core does not make for efficient cooling.
The rest of the cooling systen is also standard.
I'd be grateful for some "real world" advice on this.
Thanks
Mike

Go To E J Ward and get their supergill radiator -

Radiator - Supergill Mk 2 (Exchange)
CODE: PKC230URmk2

If you are buying this product you will also need to select the surcharge item below. This is a refundable surcharge upon receipt of your old unit.

Price: £145.00 Plus £50 surcharge for old unit.

It is a very well recoditioned unit, over £100 less than some other "Supergill" rads advertised by others (!) and it does the job perfectly.
Dont mess with anything else, just not worth it and at the end of the day, if you have cooling problems after fitting one of these there will be something more serious causing it.

Cheers,

[Bob Heritage]

Whilst we are on this topic I figure I may as ask about the viscous fan coupling.

How can you tell if the coupling is worn? Does the fan spin at the same rate when hot and cold etc.? Mine seems to be ok but when the Kenlowe fan is operated it can at times actually turn the mechanical fan, albeit very slowly...

Spin the fan blades manually, they should not spin more than about 2 blades distance. Try moving the fan to and fro (front to back) and see if there is any play in the bearing.

[Speedytriple3503]

Thanks for the input guys, much appreciated.
I saw one of Faversham's aluminium rads in a car when I picked mine up following the ZF conversion, which is how we got asround to chatting about radiators. That car was going off to Spain I think. Sure looked the business but at £800 it's not an option for me.
I think I'll try the repair route in the first instance and get the core checked. There's a firm called Bryan & Son in Tunbridge Wells I might use - they seem to have been around the classic scene for a while, but then again if a repair comes out at the same price as a recon supergill it's a tough call!
I'm tempted to try a header tank and quite like the idea of using the TR7 header tank (mainly becuase I already have one in the garage!).
That'll be another job on the list then

[rjahunter]

Thanks for the input guys, much appreciated.
I saw one of Faversham's aluminium rads in a car when I picked mine up following the ZF conversion, which is how we got asround to chatting about radiators. That car was going off to Spain I think. Sure looked the business but at £800 it's not an option for me.
I think I'll try the repair route in the first instance and get the core checked. There's a firm called Bryan & Son in Tunbridge Wells I might use - they seem to have been around the classic scene for a while, but then again if a repair comes out at the same price as a recon supergill it's a tough call!
I'm tempted to try a header tank and quite like the idea of using the TR7 header tank (mainly becuase I already have one in the garage!).
That'll be another job on the list then

I tried Rimmers 4-core upgraded radiator and found it couldn't remotely fit in the space available without comprehensively jamming the fan. I switched to Wards aluminium radiator and it fits a treat. It wasn't £800 either - I seem to recall more like half that.

Richard
Engine Bay 11.9.11002.jpg

[Firept]

Mike.
I was looking to see if the rad for a Nissan 200SX would do the job, there is an alloy version of this and they are about £130.00 pipes come out in the correct location (CORE SIZE 360x647x52)Any one else had a look at these?

Paul.

[elvimto]

If you had no cooling problems then have a rad shop give it the once over repair it, I am still running the original radiator in my MK1 i had the same thing took it to my local rad shop they fixed it and said the core, tanks were in very good condition i also have no cooling problems. There is a US company that makes a Stag radiator and one of the Canadian owners has worked with them to tweak the design specs and it fits right in. There should be a thread on here.

cheers Stuart

[Paul Goldsmith]

I tried Rimmers 4-core upgraded radiator and found it couldn't remotely fit in the space available without comprehensively jamming the fan.

The 4-row staggered fin & tube core is 57mm deep and this fits fine in our Stag, whereas the 'high efficiency' 4-row is 76mm and I see why that would be a problem.

BTW : I wish our engine bay looked that 'mint', very nice indeed

[DJT]

Running standard radiators for the past 22+ years. Had one recored by Serck when they were still operating many years ago. Had one 'standard' radiator from Paddocks (which split at the base of the filler neck after a couple of years). Current Stag has a 'standard' rad re-cored by a local radiator shop. Temperature runs fine.

As stated above, the system needs to be flushed and if there is any doubt about the cleanliness of the radiator core get it seen to. VC needs to work properly as described by Bob above. They are designed to follow engine speed up to around 2800 rpm when they should slip. At that speed, flow through the radiator should be more than sufficient. Even with a Kenlowe fan mounted on the front for back up if you wish.

Dave

[Speedytriple3503]

Thanks for the further information. On closer inspection it looks like the base of the filler neck has been repaired before so seems like a weak point on this rad. I will get the local repairer's opinion on this before deciding whether to repair or replace the rad. That aluminium one does look the business I must say, but still out of my league just now as had to spend a pile of cash on my Saab 9-5 Aero to keep the old girl going. Either way the system will get a thorough flush out before the rtad goes back in. The viscous fan seems ok.

[StagnJag]

I had one of the pipes coming out of my heater matrix come adrift. I took it to my local radiator place and they resoldered it for £20 so I can't see a repair to the filler neck of the radiator breaking the bank. Certainly got to be worth a try.

Rgds

Dave

[ChasR]

Robsport also sell alloy radiators. I believe they work out to £500 once VAT has been put on. Their uprated radiator (S-Type Radiator I believe they call it) goes for around £200.