Lotus Elan and Lotus Elan Plus 2 Forums

I am looking at replacing my narrow S4 original rad with the Coolex wide aluminum rad & I have a couple of ?s for anyone who has installed one. The top tube seems to be at quite an angle facing outward, has this been a problem for anyone & what rad hose did they use. In comparison my original rad has the tube at a right angle to the rad & the hose goes straight from the thermostat housing into the rad.
Second ? what temp sensor did you get, Coolex have several ones of different temp ranges listed.
Any comments as to the choice of plain aluminum or black painted?

In our UK Weather ( which I`m sure is getting hotter in the Summer ! ) , I`ve been very happily using the Coolex Fatboys in my S4`s for over the last 10 years ... without any overheating issues whatsoever ... not even when queing to get on the Le Mans Track Parade , for over 45 minutes at idle in temperatures above 80 degrees ...

However , as road cars only ... used all year around ... I use a 92/87 fan switch ( equates to approx 95/90 on the upstream dash "gauge" ) ... which is nearer the original Lotus recommendations ... because I want a fast warm up , a nice hot heater ... & general efficient running ....

I am aware , that the power boyz recommend a much lower rad` switch ( say 82/76) .... but I don`t see the point on a road car , running around with the fan inefficiently ( & unnecessarily) on most of the time ... with all the problems a too cold engine can also bring ...

I`ve also never needed to have a manual overide switch ( to bring the fan on early in traffic ) , as a well maintained system like the Coolex one , works & copes perfectly fine as it is ...

Hope this helps : )

Paul .

I have installed the wide coolex in my '68 Fed S4 a few years ago, it fitted like the stock one (some initial fettling with the angle to clear the fan, that I later replaced with an electrical one). The stock radiator has a bit of an angle so that the hose clears the cam cover, I did not have specific photos of the new radiator, a sign that it did not raise any issue (I found a few unrelated ones to show clearance : no problem with a stock hose - rad cap is as high as originally, so I cut the foam around it so that it would not press up). I opted for a black finish, alloys can be a pain to get the paint to stick and they did a perfect job at it, it looks very much stock from a distance.

It's interesting that your original wide rad is on an angle, is that typical for them? My narrow width one is parallel to the engine.

I fitted a Coolex rad to my S4 and I found the angle of the top hose tube to be fine with the standard rubber hose. I fitted my own sensor and didn't opt for their one. As far as I am aware the rad should be parallel with the front face of the engine.