Lotus Elan and Lotus Elan Plus 2 Forums

Hello,
My S4 Elan SE (on Strombergs) has a problem with its getting too hot when stuck for ages in traffic in the summer months.

I am wishing to keep my S4 Elan original, so whilst I have done all the usual "period" things (flushed the system, fitted the foam strips and the Sprint ducting panel, made the two holes in the left inner wing, which together improved things considerably) I am hoping to avoid disfiguring the car with a modern radiator and/or a modern fan or fans.

My Elan runs cool enough even in the summer so long as it is moving - but in hot weather it overheats when stuck still for, say, 15 minutes in traffic.

Q1: I have considered fitting a mechanical cooling fan (in addition to the standard electric one). The earlier Elans had a mechanical fan, which presumably over-cooled in the winter and also robbed a few BHP. But what about fitting a thermostatically controlled viscous clutch fan? Has anyone any experience of these, particularly on an Elan? Even know which make / model would bolt straight on?
Q2: I have also considered using Water Wetter. Any experience of using this please?

Many thanks,
Tony

Tony,

This doesn't really answer you questions but I would have thought your best solution if you want to keep the car pretty standard would be to fit the earlier wide radiator (fitted with a 3 row core).

I think this is the route I will take for my sometimes a bit hot S4

Tony,

I have had good luck with "water wetter" in my 64 mini Cooper and my 65 Elan S2. Seems to keep it cooler by 10 per cent or so. The wider rad for the Elan may help you also, if combined with all the other measures you mention. If stop and go is the problem though, a 9 inch thermostatic fan may be the final answer.

Rob

Fitting 3 cores to current narrow radiator will help. Water wetter will help also. Both help my Elan keep its cool on 40 degree C race days. The wider early radiator with a 3 row core is the next step if you consider this an acceptable "orignal mod". Thermostatic fan clutches tend to be rare on small car engines so dont know one I could recommend.

cheers
Rohan

Hello Tony,
I live in southern Brittany and ran a Plus 2 for a couple of years with a full width 3 core radiator and electric fan without any problems at all. I now have a 1968 S4 DHC Elan on a narrow 3 core radiator with electric fan and the car only just holds its own. I have now got a full width radiator recored with 3 rows and plan to fit this as soon as possible. As has been suggested this is the way to go and since the full width radiator is standard to alot of S4 cars you will still maintain originality.

Regards George...

If you want a thermostatic viscous coupled fan, late triumph spitfires had them and I think you can still buy them new. not sure of the fitting though
Tim

I'd have concerns about adding mass to the water pump bearing.

I live in Miami and have the same overheating problem. I just started using Water Wetter and found that it does improve things. (Water Wetter with water keeps the engine cooler without antifreeze, but some antifreeze is still needed to keep the waterpump lubed-up I'm told.) I recently discovered that my lower radiator hose also was slightly kinked as well. I replaced the hose, and things got a LOT better. (You may want to check for this.) I've considered swapping out the radiator core too, but things seem to have improved markedly since I made these changes.

Gary
'71 Elan Sprint
Miami, Florida

"So far so good"...

Thanks for all your help and comments.

Just to report that I thought I'd give Water Wetter a try. I drained the "coolant" (pre-mixed antifreeze mixture) and refilled with distilled water and added Water Wetter (because according to the Water Wetter instructions you get roughly half of the improvement just from using water rather than antifreeze mixture)

I've been driving the car in conditions when it would have been struggling, and it's been a big improvement - I would say 5 or 10 ?C cooler.

I'll go back to antifreeze mixture over the winter, of course.


Tony

Another thing to bear in mind is that antifreeze does more than what it says on the tin - it also protects alloy engines and heads from internal corrosion. I ran an all-alloy V8 for many years and the owner's handbook stated that, in the absence of antifreeze, you must add a commercially available corrosion inhibitor, otherwise your engine would be wrecked from the inside. Does water wetter contain this inhibitor too?

hatman wrote:Another thing to bear in mind is that antifreeze does more than what it says on the tin - it also protects alloy engines and heads from internal corrosion. I ran an all-alloy V8 for many years and the owner's handbook stated that, in the absence of antifreeze, you must add a commercially available corrosion inhibitor, otherwise your engine would be wrecked from the inside. Does water wetter contain this inhibitor too?

Yes, they've thought of that. The bottle says "Water Wetter provides excellent corrosion protection for modern cast iron, aluminium and brass systems".

It does also say "at least 15% antifreeze should be used in street vehicles" - but I've taken that to mean "... in Winter" - does anyone know otherwise?

The test figures they quote on the bottle (in ?F) are:-

50%Glycol / 50% Water : 228?F
50/50 + Water Wetter : 220?F
Water only : 220?F
Water + Water Wetter : 202?F

228?F less 202?F = 26?F = 14?C cooler

I've said 5 to 10 ?C (but then I'm not in sales....)

Hope this helps,
Tony

In my opinion, viscous fans aren't a lot of good, they have a short service life and are very heavy and bulky (short read 40-60Kmiles) Also they are very expensive. You'll need an adapter making to fit the twink water pump as well. I'd go for the larger rad core and a modern electric fan, these move more air than the standard one, also use a lower temp fan switch so it cuts in earlier.

I'd rather sacrifice a little originality rather than cook the engine

Also the stromberg lump runs 10-15 degrees hotter any way?

regards

Mark

Tony
By adding additionl viscous fans etc all you are doing is compensating for the fact that the original small radiator is only just sufficient for the job when the cooling sysytem is in good condition.
A full width radiator is the way forward (as most replies have already mentioned).
The problem with fitting old style fans is that they flow less air than modern equivalents. My modern Pacet fan blows lots of air and comes with adjustable thermostat etc.
If you really want the original look then a replica aluminium radiator sprayed black might be a way forward.

Clive

Hello Mark and Clive and thanks to you too for your comments.

I've certainly given up on the idea of a viscous fan, not only because no-one has said "yes, and here's exactly how it's done" but also because of the extra load on the water pump pulley and I certainly don't want to ruin the water pump!

Yes, the Stromberg cars are known to run hotter, and I have an original "in period" road test where a road test car suffered the same over-heating in traffic problem - so this does certainly support the real truth which is the need to throw out my beautiful original radiator and fan and replace with modern improved versions.

However I remain "in denial" about accepting this, and the use of Water Wetter has made me hope that I've resolved the issue - I'll report back if ever that's not the case!

Thanks again to all,
Tony

Tony,

The next step IMO is a better electric fan. Yes it won't be original but it will work better in the stop and go conditions where you are haveing difficulty. I would select one that fixes to the front of the radiator either with thru bolts or wire ties. Pick one that fits and has a shroud at the OD of the blade tips so that all air going thru the fan must also go thru the radiator. Tip losses can be significant. This fan should also have a thermostatically controlled, variable set point control and a manual overide, with a switch on the dash board, in parallel with the thermostatic control.

This arrangement would enable the fan to automatically be turned ON when conditions warrant. If in a traffic jam, the manual switch would allow extra cooling, before the thermostatic control calls for it, preemptive cooling capability if you will. I suspect this arrangement will make the use of Water Wetter unnecessary.

Bill