Jump to content

GT6 radiator leaking - options.

brian GT6.

Recommended Posts

The radiator on my GT6 is leaking where the car is in storage. 


Just after some views on the best options in terms of outcome against value for money.


I could:


1) Try to get the radiator recored. not sure of cost.


2) buy a reconditioned or new radiator from the usual trumph parts people. I think they are around 200 - 250 pounds.


3) Get an aluminium radiator. Radtec sell one for 500 quid.


I've never had cooling problems with my gt6 but I know they are a bit marginal. Would an aluminium radiator be worth the extra??







Link to comment
Share on other sites

Alloy rad? For £500? You are danger of being had!


Alloy rads from moderns can fit fairly easily. If searching here doesn't find advice, the look on CT.

SofS has a Honda Civic rad, that needed a bit of fettling - there are easier options, but mine was £80.



Link to comment
Share on other sites

Hello Brian.


Any joy on the subject ??


Where about are you located, as it may help with identifying the best option for a rad refurb etc ??


If you enjoy fettling then John's suggestions are a good route to follow if it fits your criteria. I'm certain a few TSSC GT6 owners will either have done as such or certainly made significant enquiries as to possible options with a modern rad.


It would be useful to know, as Clive intimated, as to where you think the leak is on the coolant system / rad.


The more facts we have the more we can help - well that's the theory any way !! :rolleyes: 





Link to comment
Share on other sites

A recore to three row modern core is around £120 (based on my last Herald recore). There are companies all over the country, try a quick Internet search around your location.

You can probably fit any modern radiator provided you don't mind a dogs dinner of large hoses everywhere and the word "Honda" or "Nissan" glaring at you every time you open the bonnet.

Aluminium rads are (or were very recently) on eBay for less than £200 (from China I think) but it's a toss-up as to whether they're really any better for normal road use. 

Link to comment
Share on other sites

Hello Aidan.


5x cores - are you sure !!!


I think the GT6 / Vitesse rad chassis is only wide eneough to take 3 rows; which I presume you mean instead of cores.


If it does have 5x rows, I'm impressed.


Does the car reach normal operating temperature or does it run slightly under its normal needle position ??


At the end of the day it's working for you, but just curious and certainly interested.





Link to comment
Share on other sites

Sorry Richard you are completely correct it's a five row and not core! Doh!!


Here's the eBay number




Yes the thermostat opens and closes about five to ten times until the temperature settles just above the thermostat opening temperature


It's definitely worked for me anyway



  • Like 1
Link to comment
Share on other sites

I had a pin hole in the top cap section of my original radiator which stopped the draw back from the expansion bottle. I replaced it 18 months ago with a re-cored version with a modern triple core, bought from Triumph Recycler (Simon), who advertises in The Courier at better rates than his eBay site. It takes just short of a litre more water and the car seems to run slightly cooler (although I'm not sure why, as the thermostat is the same - although that will be changed soon as I have a leak from the housing...).



Link to comment
Share on other sites

Hello Gully.


I wrote an article for another classic car club magazine of which I have a pasted an edited section on here that should answer your improved cooling situation:


Well my Sunbeam Alpine has taken on a few modifications and one of the upgrades on my list was to increase the cooling capacity & efficiency of the standard radiator. The Alpine runs with a double core unit consisting of 34 flutes per row giving a total of 68 flutes and is pretty much the standard set-up on these and other similar vehicles of that era. The standard rad works, but if outside temperatures increase significantly and traffic crawls the inevitable coolant gauge needle climbs. To add to these woes the car runs with an alloy head, so this requires slightly more care & attention than a cast iron head which is a bit more forgiving with heat duress.


Before the sages amongst you say rad flush, inhibitor, blah blah etc and all the other top tips, I can say that the cooling system is in fine condition with all the “beauty products” already added to help !! However, poor cooling was not the reason for seeking the assistance of “Bryan & Son” but to revamp the rad from twin core to triple core with a high performance density cooling matrix. Just the phrase makes it sound 100% more efficient !!


As mentioned the standard 2x row rad has a total of 68 flutes, but the triple row rad with its modern high density core has 52 flutes per row, giving a total of 156 flutes. Those of you in to statistics will see that is a 129% gain.


If you look at the photos you will see the visible difference between the two radiators – note the extra flutes, their close proximity to each other and also the high density fins of the three core rad. As is the case with a lot of standard classic car rad's the actual radiator frame is generous in proportions and that of course lends itself to the increased width of the uprated core, again you can see the space availability in the photo. If your existing core is pretty much the width of the rad frame, then it's very unlikely you will be able to have an extra row. However all is not lost, as modern high density performance cores can be fitted still comprising of two rows. It is important to remember it's not the number of rows that help the cooling BUT the number of flutes and additional matrix fins which assist the cooling process. Basically, more flutes means more water means larger cooling capacity and of course the more fins a matrix has the better it can dissipate the heat from the radiator.


You might think that endless rows in a radiator is the way to go. That is not the case, as anymore than three rows will start to reduce airflow through the radiator and the furthest row away from the front of the car (or closest to the engine) will never get the required air stream it requires to aid the cooling process. In fact it will remain largely non-cooled and will be returning hot water back in to the system; the very opposite of what is required.


So in a nut shell, you have more rows and flutes with more water within and of course having a modern high performance matrix the radiator is able to cool water far more efficiently due to the dissipation of heat via this matrix. All-in-all a much better set-up; I have included a few pics to highlight the differences in the matrix; hope it's of interest ??








Link to comment
Share on other sites

Thanks for the extract from your article, Richard. I guess I should have been a little more specific in my musings - whilst I understand the greater cooling efficiency, my question is why that would make the temperature gauge show the temperature at the point of the sender (essentially where the water is exiting the engine) as being lower. I would have thought the thermostat would have responded to keep the temperature at that point the same as before through lower flow? The benefit of the more efficient radiator would be lower flow generally, and better cooling capacity in traffic etc.


Aiden - I've a new thermostat housing to fit as mine appears to have corroded. The Haynes manual indicates to look out for this when changing the thermostat, so it was obviously a problem back in the 70's! There are some different quality gaskets around - the one from the Club shop is very thin, whereas the one from James Paddock that accompanied the housing is much thicker: almost cardboard. Hopefully one will seal with a smear of sealant!



Link to comment
Share on other sites

I've just had my Herald's radiator re-conditioned by 'Commercial Services' in Luton.  The new core is still 2 rows deep, but around 10 more tubes per row.


It's a late Herald 1200, so uses the larger radiator.  I too had seen pricey ones on an auction site - £600!  I was warned away from un-branded auction purchases as some are said to only feature one row of tubes.


This work cost under £140 and was turned round in a day.  The radiator frame was thoroughly cleaned and painted, so the Stanpart and Coventry Pressing Company badges are retained and clearly visible.  Re-fitted last week, but not had chance for a road test yet....


A very similar price was quoted by 'Kempston Radiators' in Bedford; their first question was "Is that a big or small Herald Radiator?"  It turns out that they do a lot of refurbishment work for a local Triumph specialist, so know their stuff.


Hope that helps,



Link to comment
Share on other sites



Could it be that the thermostat is defective and also I wonder if its opertaing temperature is correct for your vehicle and finally is it the correct length; as you know thermostats do come in various heights.


A couple of years ago I converted the head on the Vitesse to unleaded. On stripping down the old head and removing the thermostat housing I found that there was no thermostat and the housing had become so badly corroded along its seating face that the PO could no longer position a thermostat in situ. To make the housing fit and work he used copious amounts of sealant - a complete bodge and would probably have been quicker to purchase  a new housing. I always suspected that there was a thermostat issue as the car took longer to warm up than it should and of course absence of such proved the point.


I managed to pick up some NOS universal gaskets at an auto jumble some time ago and they have substance to them rather than the paper thin variety; so I understand your view.


When you come to put the housing on a smear of instant gasket on its face will be fine and in addition I would put a smear of copper slip on the housing studs for easier removal of the nuts in the future.


And finally a favour if I can ask for such ?? I will be grateful if you could pop a photo of the underside of the new thermostat housing please. I have a photo of a corroded one (mine) but not a photo of a excellent condition unit. It's for a future article concerning electrolytic reaction between different metals and the importance of anti-freeze in the cooling system.


Many thanks.



Link to comment
Share on other sites

Ye still aint said where it leakin  at.


IF, its leakin at a verticle tube, then 2 optionees

1, if on out side, easy t,get at,  ye can clean area, and solder it up

can use  owt frae a 40 -100 W solder iron


2, if the tube is really shot, then ye can, { if tibe is easy t,get at } snip tbe off top an bottom


cut a wee bit of brass,or copper,  electric cable wire generally suffices,  tin them,, tine the rad bit

and solder em into place,

both of above will never leak, been there dunit.


If its just the pipe connectionees coma loose,leaking, then a blow lamp wid a shafp flame point,

clean area up, and feed new solder in

agen, been there , dun it, never leaked.yer rads leaking all owa the spot,

yer fins have mostly corroded away, then a new core will be better


Note, the side folds are steel, thee,s rust, an swell up, and can cause a pin hole,to a bigg hole beint them

as the rust has eaten / corroded thru the brass case of rad


Be wary getting re con rads, most want yer olde one back t,re core

if yer olde one is rotten on the sides, esp strap bits that curl aroond the bottom an top,

then they will most likely just rub muck off an stick it back on


Ive seen loads like this, not v good workmanship at all



Link to comment
Share on other sites

Hello Gully.


Many thanks for the photos - perfect. Looks as though you have mastered digital transfer on to the TSSC site !!


In fact compared to some other sites the TSSC upoad is a pleasure to use and is well thought out.


Once again, many thanks and very useful photos.


Best wishes.



Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Create New...