A bit hot under the collar...

[olly22n]

http://www.pacet.co.uk/BONNET.HTM

Won't improve the looks, but this might do the trick?

think i'll let it boil....

[Bahamayellow]

I am due to drive through France in Sept for my Honeymoon with wife to be obviously amd my Sprint (lucky girl - the wife that is) anyway I have the same temp problem with my car but i didn't with the previous S4 although that had the 2 venting holes on the n/s wing as in the workshop manual. The PO of my current car has decided to block these up when he restored the car a while ago. I am going to re-instate these but still wonder whether that will make a great deal of difference having read some previous posts. Therefore Olly I have looked at the following options.

1) New bigger rad - I know Cliveboy is developing a standard looking wider rad which I would prefer to the very effective but ugly looking alu rad on ebay IMHO
2) Kenlowe type Fan - worry that being fixed to the rad may cause even more disturbance of air to the rad when moving
3) Manual overide of standard fan - am definetly going to do this and put a switch under the dash.
4) I also have a 63 Cooper and as you all know minis rads are not in the best place for cooling although they do not suffer with removing hot air from under the bonnet as elans seem to but they still get bloody hot in standing traffic. A friend suggested this http://www.redlineoil.com/Products.aspx?pcid=10 Water Wetter and I have never had an overheating problem wth the Mini so will try this in the Elan. Anyone else tried this.
5) Bonnet open/heater full on is a last resort but also works

Hope this is of help Olly

[billwill]

Probably not worth the effort of wiring a bypass switch under the dash, just wire the fan bypass permanently to the ignition switch circuit but including an in-line fuse holder, then you can put the fuse in the holder in summer and take it out in winter.

In summer the fan will then run whenever the ignition key is in the ON position, i.e. (in general) whenever the engine is running.

[GrUmPyBoDgEr]

Hi Mike,

re-instate those exit holes ASAP they do a good job of getting air out of the Engine bay.
The Man "who knows" at Lotus was quite emphatic about that.
Lotus did owt for nowt!
Put some more in or make them bigger if you feel like it; it won't do any harm.
I agree with you about the Electric Fan. If you've got the space fit a "Sucker" Fan; they're not so efficient as a "Blower" but they don't reduce the intake area of the Radiator the way a Blower can.
I've heard about that "Water wetter" stuff & know that people swear that it's the Dog's danglies.
I don't understand how it works & so far have not heard a feasible explanation; so I consider it to be a splash of "Pixie Dust" as one of our posters describes these "Magic Potions".
Nevertheless why not give it a go, it can't cost a lot but you will only be able to confirm its capabilities if you do just only that.
Hope your Honeymoon goes well, seems you've found an understanding Girl; who else would marry an Elan owner.

Cheers
John

[collins_dan]

Is a pusher fan really more efficient/effective than a puller fan? I always thought it was the opposite.

I was planning to change from 1 10" pusher fan to 2 8" puller fans, 1 by the inlet, 1 by the outlet. I could always mix it up and make the inlet one a puller, so it would also clear the air by the header in addition to drawing air through the radiator. The other could be a pusher on the outlet side, if that's deemed more effective than pulling.

I have one of those big ugly, but very effective alum radiators, but my current 10" fan doesn't seem to effectively push air through it. It's quite a bit thicker than the original.

Curious to get opinions on pusher vs puller fan effectiveness.

Dan '70 S4

[types26/36]

Is a pusher fan really more efficient/effective than a puller fan?

According to this site a puller fan is more efficient.
http://perma-cool.com/faq/efans.html#efficient

[69S4]

Probably not worth the effort of wiring a bypass switch under the dash, just wire the fan bypass permanently to the ignition switch circuit but including an in-line fuse holder, then you can put the fuse in the holder in summer and take it out in winter.

In summer the fan will then run whenever the ignition key is in the ON position, i.e. (in general) whenever the engine is running.

Not a good idea (IMHO) if you're running a dynamo. The std Lotus fan takes about 8 amps and in traffic with the lights on (winter) or wipers running (summer!) my voltmeter would show a substantial discharge going on. Even with an alternator upgrade things are marginal in traffic with just 12.5v available when the fan is running. Switching the fan off when you start moving at least allows a bit of pay-back time for the battery.

I've always assumed that a puller fan was more efficient than a pusher but with the std S4 engine compartment layout there's no room for anything between the rad and the engine so a pusher, pushing harder. looks the easiest to fit I've only had a quick look at this but the std narrow rad is about 18" wide so two 9" fans side by side should just about cover the whole of the fin area. Whether other bits (eg the bonnet spring) will get in the way remains to be seen.

My S4 didn't come with holes cut in the wing so maybe Lotus discovered their benefit after mine rolled off the line. I subsequently retrofitted the holes but tbh haven't noticed much (if any) difference. I can't envisage a mechanism where they would be much help with cooling when the car is stationary. Yes when the car is moving but traffic jams seem to be the biggest problem and there won't be any pressure differential across the hole then.

Water Wetter seemed like a great concept when I first heard of it (quite a few years ago now). Reduce the surface tension of the coolant and it'll transfer more heat to the rad. I tried a DIY version using various surfactants from a lab I worked in but again I didn't see much difference. If anyone is thinking of exploring this further I'd suggest giving washing up liquid a miss! Water Wetter seems to be a bit more sophisticated than that.

[olly22n]

My Elan doesn't have these holes in the inner wing, has anyone got any pictures?

[GrUmPyBoDgEr]

Hi,

I appologise if I've put the Cat amongst the Pigeons on the "sucker/blower Fan theme.
Whether one works better than the other was not really where I was coming from.
My previous Car maker employer always used sucker Fans, even after switching from Engine driven to Electric ones.
The thinking was that blower Fans always "shade" part of the Radiator Core from the incoming Air & the smaller the Radiator the less you paid.
The back of the Radiator can be shrouded in order to optimise the function of a sucker Fan without detriment to the incoming Air & what goes in must come out.
That would be disastrous with a blower fan, blocking all of the Radiator except for the Fan opening.
On the bigger Engined Cars the Shrouds sometimes had hinged flaps in the shroud that would be forced open by incoming air when traveling at higher speeds.
Those valves would be sucked shut by the Fan at lower speeds or Idle.
Result higher efficiency in both modes.

On the "Water Wetter" front I suppose that a reduction of surface tension would permit the Coolant to enter the very tiny indentations left by the Core Sand & thus cool a larger area but I'm not convinced.

Cheers
John

[Bahamayellow]

My S4 didn't come with holes cut in the wing so maybe Lotus discovered their benefit after mine rolled off the line. I subsequently retrofitted the holes but tbh haven't noticed much (if any) difference. I can't envisage a mechanism where they would be much help with cooling when the car is stationary. Yes when the car is moving but traffic jams seem to be the biggest problem and there won't be any pressure differential across the hole then.

Water Wetter seemed like a great concept when I first heard of it (quite a few years ago now). Reduce the surface tension of the coolant and it'll transfer more heat to the rad. I tried a DIY version using various surfactants from a lab I worked in but again I didn't see much difference. If anyone is thinking of exploring this further I'd suggest giving washing up liquid a miss! Water Wetter seems to be a bit more sophisticated than that.

The holes in the inner wing are reccomended within the Workshop Manual and describe what to do. Not sure whether this was a dealer fit or diy?

Water wetter has worked in the Mini so will give it a go although to be most effective it says you should put as littles antifreeze as possible as antifreeze holds heat!!

[Bahamayellow]

My Elan doesn't have these holes in the inner wing, has anyone got any pictures?

Have a look at this link from Brian download/file.php?id=6946&mode=view

[saildrive2001]

Go to this web site http://www.evanscooling.com/coolants/ & look at the NPG+ product. A friend here in hot Canada (31C yesterday) used it succesfully in his 7 & is also using it in his recently rebuilt Europa. It's a little expensive but from my friends experience is well worth the cost. An added advantage is that you don't have to pressurize the system, less strain on the hoses & radiator core etc.
I will be using it in my restored S4.
Usual caveat, no connection with Evans.

[johnaspencer]

My Sprint used to run well round above 110, almost into the oil pressure, in heavy traffic after running hard e.g. hitting a jam on the motorway. I have fitted a TTR aluminium radiator and never looked back. On the open road it runs about 70ish even with 150bhp on tap.

There is a cheaper ally rad often on ebay which looks like it may fit the bill and can be specified with Kenlowe fan. No experience of this.

Even without a fan the TTR radiator is a huge improvement on the old Stanpart radiator with a fan. The Pacet fan for the TTR radiator is about the same cost as a Kenlowe and can push or pull. I never hear it kick in (it is very quiet) and have never exceed 90 even in heavy traffic.

I met a man at Harewood hillclimb who had a Polo radiator in his competition car and paid under a ?100. He said many small new cars now have high performance radiators with multicores which might fit. It is just a question of fiddling with mounting brackets.

Of course the originality goes so do keep the old one just in case you ever plan a concours rebuild.

[billwill]

The posting in the other thread about the new type thermostat made me realise that one way of dealing with summer heat in traffic jams, for those Elans (most of them?) that have fitted electric fans, would be to refit a fan on the mechanical fan pulley in addition to the electric fan, during the summer.

On the engine it would act as a puller and, as mentioned in the other thread one, could possibly get a suitable multi-bladed plastic fan instead of the original 4-blade steel cross.

From a breakers yard?

[rgh0]

Water wetter certainly works well in my Elan on the track at high speed

It lowers the viscosity of the coolant. This increases the effective Reynolds number in the flowing coolant. Heat tranfer both from engine to coolant and coolant to radiator increases with increasing Reynolds number. The science is sound which is why it works.

However if the radiator to air side heat transfer is the limit which is the case in traffic jams then water wetter will not help you much in that situation.

cheers
Rohan