S Series radiator options.
Discussion
I will start by apologising, this post may go on a bit but thought it worth doing as it may be of use to someone.
This is something I have been thinking about for a couple of years, but since my S has been in pieces longer than that (I know, I know
) it was not urgent.
Well last week it became more urgent, the time had come to fit a rad. I looked at my grotty original item, tested it and unsurprisingly found a couple of leaks.
This left me with 3 options as I saw it.
1) Re-core - quoted approx £140 +vat at the local radiator fix it man. Possibility.
2) Alloy replacement - approx £450
not of my hard earned!
3) Try an alternative rad from something else.
Now I have had a possible alternative in mind, as I said, for a couple of years and after a day or two mulling the options I decided to go for it and placed an order.
It arrived Thursday around lunchtime, after about an hour looking, thinking and measuring, I decided that it would fit and set to work.
The radiator is an after market, all alloy unit designed for a pre 2000 model Subaru Impreza Turbo.
These can be had on Ebay for around £125, I paid a little less due to bidding on an auction. I didn't expect it to be black (usually more expensive) but it suits me as I don't really do “bling”.
Size wise it is pretty close to the original, about 2” wider but that doesn't seem to be a problem.
The rad is not a direct drop in replacement but is not too difficult to fit either. It has two locating pegs on the lower edge just like our cars but unfortunately they are approximately 10mm closer together on this rad. A plate could be fitted to the brackets on the chassis and then drilled to the correct dimensions for the mounting pegs but I opted to cut the brackets out, move them in 5mm at each side and weld them back in.
The top fixing is fairly simple. I cut the old mounting brackets from the rad mounting frame and made some new bolt on ones. These have a peg welded on that fits into a rubber bush in the mounting bosses in the new rad. I will make the nuts on the mounting frame captive when finished.
An added bonus of this rad is that it has a drain tap at the bottom and a small vent pipe at the top which will be joined into the vent from the thermostat housing to the swirl pot. When done this means that the rad will self bleed meaning nomore worries about radiator air locks.
I have run the car up in the garage to test the new installation. I tested it with the car at idle speed and at a constant 2500rpm. Bearing in mind being inside and stationary means no natural air flow, in both tests when the temperature came up the fan had no problem bringing it back down to normal and the fan shutting off again.
Although I have not yet tested on the road I am confident that this setup will work well and don't foresee any issues.
I realise that this change may not be something every owner can do but hope it may be of use to at least some of you and does add another option when faced with a past it's best radiator.
Here are a few pics of the installation, just because, well, we all like piccies don't we?
Please ignore the fact that everything looks a bit rough, nothing has been fettled and finished but will be now that I know everything works.
Cheers,
Carl.
This is something I have been thinking about for a couple of years, but since my S has been in pieces longer than that (I know, I know
) it was not urgent.Well last week it became more urgent, the time had come to fit a rad. I looked at my grotty original item, tested it and unsurprisingly found a couple of leaks.
This left me with 3 options as I saw it.
1) Re-core - quoted approx £140 +vat at the local radiator fix it man. Possibility.
2) Alloy replacement - approx £450
not of my hard earned!3) Try an alternative rad from something else.
Now I have had a possible alternative in mind, as I said, for a couple of years and after a day or two mulling the options I decided to go for it and placed an order.
It arrived Thursday around lunchtime, after about an hour looking, thinking and measuring, I decided that it would fit and set to work.
The radiator is an after market, all alloy unit designed for a pre 2000 model Subaru Impreza Turbo.
These can be had on Ebay for around £125, I paid a little less due to bidding on an auction. I didn't expect it to be black (usually more expensive) but it suits me as I don't really do “bling”.
Size wise it is pretty close to the original, about 2” wider but that doesn't seem to be a problem.
The rad is not a direct drop in replacement but is not too difficult to fit either. It has two locating pegs on the lower edge just like our cars but unfortunately they are approximately 10mm closer together on this rad. A plate could be fitted to the brackets on the chassis and then drilled to the correct dimensions for the mounting pegs but I opted to cut the brackets out, move them in 5mm at each side and weld them back in.
The top fixing is fairly simple. I cut the old mounting brackets from the rad mounting frame and made some new bolt on ones. These have a peg welded on that fits into a rubber bush in the mounting bosses in the new rad. I will make the nuts on the mounting frame captive when finished.
An added bonus of this rad is that it has a drain tap at the bottom and a small vent pipe at the top which will be joined into the vent from the thermostat housing to the swirl pot. When done this means that the rad will self bleed meaning nomore worries about radiator air locks.
I have run the car up in the garage to test the new installation. I tested it with the car at idle speed and at a constant 2500rpm. Bearing in mind being inside and stationary means no natural air flow, in both tests when the temperature came up the fan had no problem bringing it back down to normal and the fan shutting off again.
Although I have not yet tested on the road I am confident that this setup will work well and don't foresee any issues.
I realise that this change may not be something every owner can do but hope it may be of use to at least some of you and does add another option when faced with a past it's best radiator.
Here are a few pics of the installation, just because, well, we all like piccies don't we?
Please ignore the fact that everything looks a bit rough, nothing has been fettled and finished but will be now that I know everything works.
Cheers,
Carl.
) what fan are you running?Already done. Plentiful supply thanks to the popularity of the Subaru in motorsport.
Mine is a Subaru Impreza STi 1999 model. Not sure which model name or time period this covers. I think 2002 was the change over year.
I got some stainless bobbins and some genuine Subaru upper mount brackets to keep it as 'stock' as possible. Such an easy mod that the Reserve will be getting the same.
Even the hoses can be retained.
Mine is a Subaru Impreza STi 1999 model. Not sure which model name or time period this covers. I think 2002 was the change over year.
I got some stainless bobbins and some genuine Subaru upper mount brackets to keep it as 'stock' as possible. Such an easy mod that the Reserve will be getting the same.
Even the hoses can be retained.
mk1fan said:
Already done. Plentiful supply thanks to the popularity of the Subaru in motorsport.
Mine is a Subaru Impreza STi 1999 model. Not sure which model name or time period this covers. I think 2002 was the change over year.
I got some stainless bobbins and some genuine Subaru upper mount brackets to keep it as 'stock' as possible. Such an easy mod that the Reserve will be getting the same.
Even the hoses can be retained.
Mine is a Subaru Impreza STi 1999 model. Not sure which model name or time period this covers. I think 2002 was the change over year.
I got some stainless bobbins and some genuine Subaru upper mount brackets to keep it as 'stock' as possible. Such an easy mod that the Reserve will be getting the same.
Even the hoses can be retained.
Yeah I remember a pic of it resting in place and did ask if it was the Subaru rad at the time as I thought I recognised it. Didn't know you had fitted it as you never mentioned it again.
Does it as work well in real use as it seemed to in my garage tests?
I'm another one dealing with radiator issues at the moment after finding a puddle of coolant under the car.
I decided in the end to get the original recored but with a additional core added. This keeps its originality and helps keep it cool when stuck stationary in heavy traffic when out in a hot summers day. Did have issues with this in the past and almost overheated in central London one day. It also is easily repairable too if it does have problems, can continually be recored if required. Unlike a alloy rad. Hopefully over cooling won't be a issue for me now!!
I decided in the end to get the original recored but with a additional core added. This keeps its originality and helps keep it cool when stuck stationary in heavy traffic when out in a hot summers day. Did have issues with this in the past and almost overheated in central London one day. It also is easily repairable too if it does have problems, can continually be recored if required. Unlike a alloy rad. Hopefully over cooling won't be a issue for me now!!
The Big G said:
I decided in the end to get the original recored but with a additional core added. This keeps its originality and helps keep it cool when stuck stationary in heavy traffic when out in a hot summers day. Did have issues with this in the past and almost overheated in central London one day. It also is easily repairable too if it does have problems, can continually be recored if required. Unlike a alloy rad. Hopefully over cooling won't be a issue for me now!!
I fully agree with all of that, recore was one of the options and still is should it ever be required as I still have my crusty original rad.I just decided to try some newer technology which came with the benefits of a self bleeding rad, a functioning drain tap and in this case was £60 cheaper.
When you say you now have an extra core, the rad should have been a 3 row core already, does that mean that yours is now a 4 row core?
O/T a little but maybe if somebody here has more knowledge they could help me out.
On many threads about cooling systems I see people mention/question the possibility of having over cooling problems.
Now I may be being a bit thick but, surely, if the correct thermostat is fitted and is working correctly, then over cooling should not be possible.
As I understand it when the engine is cold, the stat is closed, heavily restricting coolant flow through the rad. As it warms the stat begins to open allowing flow through the rad. At a pre-determined temperature the stat is fully open allowing maximum coolant flow through the rad.
Now if the engine coolant temperature begins to drop then the stat will start to close again, restricting flow and allowing he engine to remain at optimum temperature.
If all of this is happening as it should I fail to see how, even if a huge rad was fitted, that over cooling can be an issue.
If over cooling is an issue, it seems to me that it is the opening temperature of the thermostat that is too low and in fact nothing to do with the size of the cooling radiator.
Happy to be corrected if anyone can explain to me why this would not be the case or I am over simplifying it.
Cheers,
Carl.
On many threads about cooling systems I see people mention/question the possibility of having over cooling problems.
Now I may be being a bit thick but, surely, if the correct thermostat is fitted and is working correctly, then over cooling should not be possible.
As I understand it when the engine is cold, the stat is closed, heavily restricting coolant flow through the rad. As it warms the stat begins to open allowing flow through the rad. At a pre-determined temperature the stat is fully open allowing maximum coolant flow through the rad.
Now if the engine coolant temperature begins to drop then the stat will start to close again, restricting flow and allowing he engine to remain at optimum temperature.
If all of this is happening as it should I fail to see how, even if a huge rad was fitted, that over cooling can be an issue.
If over cooling is an issue, it seems to me that it is the opening temperature of the thermostat that is too low and in fact nothing to do with the size of the cooling radiator.
Happy to be corrected if anyone can explain to me why this would not be the case or I am over simplifying it.
Cheers,
Carl.
The way TVR configured the cooling system on the S V6 the coolant circulating the system is exposed to the rad even when the thermostat is closed.
That said, you are right that the thermostat should open as required.
Fitting the Ford (or cheaper VW item) oil/coolant heat exchanger should help regulate / even out the temp across the engine and mitigate the overcooling of a larger rad.
That said, you are right that the thermostat should open as required.
Fitting the Ford (or cheaper VW item) oil/coolant heat exchanger should help regulate / even out the temp across the engine and mitigate the overcooling of a larger rad.
Agreed, assuming the correct thermosat is fitted. The thermostat should prevent the water flow until the engine has reached the correct operational temperature. If by some miracle the radiator then 'overcooled' the water the thermostat would close again. In practice if the cooling system is very efficient the thermostat might well not open completely, effectively slowing down the flow, reducing the volume passing through the rad. Sounds like good news to me as it gives a built in safety factor in the cooling system.
The only real issue I can see arising with a very efficient cooling system would be some loss of effectiveness in the heater system in cold weather. Hence cars running in very cold climates often have 'blinds' to reduce the rad area. Given the startlingly good efficiency of the average S heater I cannot see that as a problem!
In extreme cold I suppose the differential between the temp of the water entering the engine and that leaving might be a problem but I cannot see that being sufficient on an S. If you want to go Ice Road Trucking with an S I can imagine some other problems arising first!
The only real issue I can see arising with a very efficient cooling system would be some loss of effectiveness in the heater system in cold weather. Hence cars running in very cold climates often have 'blinds' to reduce the rad area. Given the startlingly good efficiency of the average S heater I cannot see that as a problem!
In extreme cold I suppose the differential between the temp of the water entering the engine and that leaving might be a problem but I cannot see that being sufficient on an S. If you want to go Ice Road Trucking with an S I can imagine some other problems arising first!
I should perhaps have added one point. Overcooling of an engine bay can give rise to problems, it was reasonably common at one time for cars to suffer carb icing if the engine bay became too cold. I suppose it might just be possible to get icing in extreme conditions in the K Jet system which has the remote metering head well away from the engine. Never actually heard of it though.
Thanks for confirming what I thought chaps.
mk1fan said:
The way TVR configured the cooling system on the S V6 the coolant circulating the system is exposed to the rad even when the thermostat is closed.
Agreed, that is why I also re-routed the bypass hose into the bottom radiator hose rather than the swirl pot as recommended by Griffinr some time ago.Ceejay73 said:
Agreed, that is why I also re-routed the bypass hose into the bottom radiator hose rather than the swirl pot as recommended by Griffinr some time ago.
I was wondering if anybody else had carried out the mod, the improvement on my car was quite dramatic I presume you experienced the same.Ah! re-reading the start of this thread I see you may not have got as far as running it yet.
Rob.
Edited by Griffinr on Tuesday 17th November 10:38
mentall said:
What a wonderful forum this is! Thanks to all concerned.
So presumably, for those of a penny-piching persuasion like me, this could easily be made to fit? Adequate for a 218BHP Impreza Turbo.
That appears to be a standard rad with 26mm thick core, presumably single row and may not be man enough.So presumably, for those of a penny-piching persuasion like me, this could easily be made to fit? Adequate for a 218BHP Impreza Turbo.
The one I used is the uprated aftermarket all alloy version for that model car.
Griffinr said:
I was wondering if anybody else had carried out the mod, the improvement on my car was quite dramatic I presume you experienced the same.
Ah! re-reading the start of this thread I see you may not have got as far as running it yet.
Rob.
Not seen the road yet, probably won't do until spring but have run it up in the garage and so far all seems good.Ah! re-reading the start of this thread I see you may not have got as far as running it yet.
Rob.
Edited by Griffinr on Tuesday 17th November 10:38
Carl.
Ceejay73 said:
I fully agree with all of that, recore was one of the options and still is should it ever be required as I still have my crusty original rad.
I just decided to try some newer technology which came with the benefits of a self bleeding rad, a functioning drain tap and in this case was £60 cheaper.
When you say you now have an extra core, the rad should have been a 3 row core already, does that mean that yours is now a 4 row core?
Having a play and finding differing solutions is always fun. As for number of cores, yes I believe it should have four when it returns. It's off being done at the moment but at this time of year I'm in no rush to get it back again. I just decided to try some newer technology which came with the benefits of a self bleeding rad, a functioning drain tap and in this case was £60 cheaper.
When you say you now have an extra core, the rad should have been a 3 row core already, does that mean that yours is now a 4 row core?
Gassing Station | S Series | Top of Page | What's New | My Stuff