Spitfire Mark III Electric Cooling Fan

[cliff.b]

19 minutes ago, johny said:

Yes before I changed my bearings and oil pump the tickover would go low and oil thin so that the pressure warning light started flickering😌 My brother had an old Alfa Romeo twin cam that actually had a knob on the dash for raising the tickover (separate from choke) under such conditions which I thought was a great idea...

A second choke cable arrangement connected to the throttle linkage should allow you to achieve that 🤔.

Also, when pulled out further, a cheap and effective cruise control facility 🙂

[Paul H]

33 minutes ago, Iain T said:

I like the control given with an electric fan. Sitting in a traffic jam in hot weather with only a crank driven fan and the temperature rising makes for an unhappy driver. As a boy I remember seeing many cars boiled up in summer, ok mainly due to poor maintenance but the piddly fans didn't help. 

Hi Iain, what’s the spec of your fan please ?

Paul 

[Chris A]

35 minutes ago, Iain T said:

As a boy I remember seeing many cars boiled up in summer, ok mainly due to poor maintenance but the piddly fans didn't help. 

Yes I remember the images, cars with bonnets up. as well as not having had a proper service before setting off they were usually well overloaded, inside and out!

[Iain T]

9 minutes ago, Paul H said:

Hi Iain, what’s the spec of your fan please ?

It's a Spal VA10-AP50/C-61A 12" pull fan from T7 Designs. Very good and pulls the temperature down 10C in no time, at all. 

[Paul H]

7 minutes ago, Iain T said:

It's a Spal VA10-AP50/C-61A 12" pull fan from T7 Designs. Very good and pulls the temperature down 10C in no time, at all. 

Newbie ? Can this fan fit with the existing mechanical fan setup ? 
Paul

[Iain T]

7 minutes ago, Paul H said:

Newbie ? Can this fan fit with the existing mechanical fan setup ? 

Not on a Vitesse, I had to get EP Services to mod my water pump to fit it! However some have fitted without this mod?!?! Dunno why I have less room. 

I used the Spall fan bracket        69A-075-AA0 with home made brackets to fit. 

[Paul H]

27 minutes ago, Iain T said:

Not on a Vitesse, I had to get EP Services to mod my water pump to fit it! However some have fitted without this mod?!?! Dunno why I have less room. 

I used the Spall fan bracket        69A-075-AA0 with home made brackets to fit. 

I’ll measure the gap between the water pump and the rad to compare if that’s ok ? Be next week as away at the present 

Paul

[Iain T]

6 minutes ago, Paul H said:

I’ll measure the gap between the water pump and the rad to compare if that’s ok ?

I made cardboard sections and interlocked them to make a dummy fan. 

Have fun! 

[Pete Lewis]

hand throttle was common on diesel trucks   some you turned the knob some were ratchet /clicks 

[daverclasper]

On Stroms (at least), I have read that, the Choke operates the throttle to begin with and then raises the piston for more fuel.

Never checked this with the air filter off myself.

If true, then can be used to increase the idle if need be, in hot, slow moving conditions I assume?.

Sorry, I'm not able to highlight and quote the relevant sections above on this phone?, that my reply, relates to.

[Pete Lewis]

pretty much all carbs  the choke just raises the idle speed by its cam for the first 1/2" of choke pulled 

without richening it up .

so  yes 

Pete

[Iain T]

31 minutes ago, Pete Lewis said:

pretty much all carbs  the choke just raises the idle speed by its cam for the first 1/2" of choke pulled 

without richening it up .

Yes although it does depend on the choke cam profile and how far in or out the cam screw is with the CDS carb. 

[Clive]

8 hours ago, cliff.b said:

My car temp gauge doesn't show any hotter the longer I drive, but it does if I drive hard and/or in very warm weather. But I would expect that.

Regarding oil temp, does any one have an oil temp gauge fitted? If so, what sort of temp is typical, does it vary much and is there a close correlation between oil and water temp? Wanting to understand if oil temp can rise significantly without much of a noticeable increase in coolant temp? 

 

I know somebody who has one on his vitesse. Reckons the oil stays at sensible temps. Until it goes on track where the oil temp RAPIDLY rises tho 120+ degrees. Bt using a quality synthetic oil will mean that is no problem, mineral oils will fall apart quickly though. 

So unless you are driving at 6000rpm for more than 5 minutes you should be fine. 

[cliff.b]

2 hours ago, clive said:

I know somebody who has one on his vitesse. Reckons the oil stays at sensible temps. Until it goes on track where the oil temp RAPIDLY rises tho 120+ degrees. Bt using a quality synthetic oil will mean that is no problem, mineral oils will fall apart quickly though. 

So unless you are driving at 6000rpm for more than 5 minutes you should be fine. 

Probably won't be happening. Half an hour at 4000RPM is more likely.

[Clive]

26 minutes ago, cliff.b said:

Probably won't be happening. Half an hour at 4000RPM is more likely.

That won't bother oil temps at all. 

[Paul H]

9 hours ago, clive said:

That won't bother oil temps at all. 

Academically how about 5 hrs at 4K . Currently on long journeys my Vitesse is around 3.2k

Paul 

[Clive]

3 hours ago, Paul H said:

Academically how about 5 hrs at 4K . Currently on long journeys my Vitesse is around 3.2k

Paul 

so 80+mph? I doubt that will be an issue. Just use a decent oil. 

Kipping used to run 1500 heralds on their fleet. His recommendation to make then last despite the best efforts of the enthusiatic employees who drove them (thinking they were Nigel Mansel back in the day) was to use Mobil 1 fully synthetic oil. Stopped the crank failures..... It is in the kipping catalogue. Sadly the appropriate grade is no longer available, but there are some excellent synthetic oils that will put up with the abuse that will cause a mineral oil will fail. 

But the current testbed for oils is the RBRR, 2000 miles in 48hrs. Many use VR1, penrite, Millers CSS etc. I used the millers, in fact I absentmindidly left it in teh engine for 3 years, including 2xRBRR and a trip to Spa including tracklaps. Still good after about 10K miles. No change in oil pressure (not having a oil pressure gauge in the new dolomite. And not got one in my spitfire)

[Colin]

Hi guys.

Appreciate we seem to be talking Spits & larger engined Herald/Vitesses.

Elsewhere, I've just written about my having read comments regarding adverse effects of electric fans.

I bought such an item (Club) for my 1147 Herald Saloon. But haven't fitted it yet.

My intent was to achieve the 2 main things one hears about, by fitting such an electric fan:- 

1) Engine quicker to reach operating temperature

2) Frees up extra horses, no metal fan being turned unnecessarily.

Now, I assumed both were mutually exclusive, but earlier in this convo, there seems to be a view that the car can carry both types - which seems to be the best of both worlds (I guess, space permitting).

This, in the world ofmore frequent traffic jams and increasing world temperatures, the electric could/would cut in to augment cooling alongside the fixed metal fan, should the engine temperature reach such levels.

No? Is having bith achievable? 

Best,

Colin (Winn)

[johny]

well if air is already moving a fan does less work so that once a car is travelling its fan, electric or mechanical, isnt doing very much in terms of moving air or consequently consuming energy. The same applies with having a mechanical and electric fan moving the same air, one does the work while the other isnt helping much so you might as well stick with one or the other....

This also applies to the warm up if, as you should do, you start up and drive off pretty much straight away the radiator is cooling the water in it regardless of whether you have a fan running or not so the warm up time isnt altered.

[johny]

oh and another thing, dont forget that your temperature gauge indication is meant to go up and down unlike moderns which either have no gauge or have electronics to hold the reading steady to stop people worrying.

Its a self regulating process because as the coolant temperature goes up the greater difference between it and air temperature allows more energy to be transferred so a new balance temperature is reached. This should then hold steady until the heat being produced (engine load) or heat being removed (controlled by air flow and its temperature) changes and the process is repeated...

[cliff.b]

As I explained previously, I refitted a mechanical fan but left the electric ones in place so although unplanned, I have both.

The thermostat probe for the electrics is in the radiator return pipe, set at 75C & now they only come on if I am stationary after "enthusiastic" driving. Before I refitted the mech fan the electrics would come on anytime I slowed down below about 30 so I assume at that point, the return temp was at least 75C. The temp gauge would rise to just over halfway.

I can adjust the thermostat from the driving seat so by turning it until the fans come on I can determine the temp in the radiator return pipe while on the move. So far, during normal driving, it stays at about 60 to 65C with the temp gauge just below halfway. 

When I first fitted the electrics I experimented with different thermostat settings and at 65C, they were on almost continually, so I know this goes against conventional wisdom, but in my car, at least, it seems the mech fan gives a lower radiator return temp at any driving speed.

 

[Paul H]

Is there enough space to have the same setup on a Vitesse mk2

Paul 

[Mjit]

I think for most of our cars an electric fan set to 65°C is rather crazy and way too low a temp.  I mean you're probably running a themostat that doesn't open until 82°C so you'd literally just be cooling the water sat in the radiator.

The Rovotec fan controller I had on my Spit. died during lockdown and I've replaced it with a simpler system with swappable, fixed-temp. switches.  Their guide is to aim for a switch-on temp that's 12°C to 18°C hotter than the themostat opening temp.  I seem to remember the set-up for the adjustable Rovotec controller was something similar - set 'stat to hottest setting, get it up to temp a the needle past the middle line, set 'stat to coldest setting, then when the needle drops to the middle line turn the 'stat hotter until the fan kicks out.

[johny]

course it depends on the equipment as I cant believe theyre very accurate and also on location in the cooling system. Even our temperature gauges are variable so really it comes down to keeping the temperature, under even the hottest conditions, low enough so as not to affect the running of the engine. The correct radiator cap will protect your engine from damage but you might find erratic tick over and pinking when the engine temperature gets to a certain level so this is the point on your temperature gauge that your cooling system has to ensure is never reached...

[cliff.b]

1 hour ago, Mjit said:

I think for most of our cars an electric fan set to 65°C is rather crazy and way too low a temp.  I mean you're probably running a themostat that doesn't open until 82°C so you'd literally just be cooling the water sat in the radiator.

The Rovotec fan controller I had on my Spit. died during lockdown and I've replaced it with a simpler system with swappable, fixed-temp. switches.  Their guide is to aim for a switch-on temp that's 12°C to 18°C hotter than the themostat opening temp.  I seem to remember the set-up for the adjustable Rovotec controller was something similar - set 'stat to hottest setting, get it up to temp a the needle past the middle line, set 'stat to coldest setting, then when the needle drops to the middle line turn the 'stat hotter until the fan kicks out.

Yes, I only set it at that to find out the return temperature.

What I observed was that with the standard setup of a mechanical fan, the rad return temp was about 65C unless stationary after caning it when it rose to 75C.

That's what I usually set the thermostat at and with the mech fan removed the electric fans were coming on every time I slowed down for a roundabout, even after moderate driving.

I'm not suggesting that the car was overheating without the mech fan, as the temp gauge was still showing a reasonable reading, but hotter than it reads with the mech fan fitted.

So from what I have seen with my own car (Spitfire with wide rad), electric fans will stop a car overheating but it runs cooler with the mech fan fitted.