Rodney Dickman Lower Temperature fan switch

[DavieBow]

Hi Guys ,
i've just purchased the lower temperature fan switch kit off Rodney Dickman ,
he's just advised me that he has set up a specific web page on his site now , so us guys can link straight to it ,

here you go
http://rodneydickman.com/catalog/produc ... cts_id=444

[French_elans]

Hi,
A question : can you confirme the thread of the thermo-switch ?

Is it 3/8 NPT (conical) as rodney or M16 as WikiLec information ?


FE

[Brit-Car-Nut]

The Dickman switch fits correctly. Make sure you get the adapter wire / pigtail as the connection is different.

BTW, it is 3/8 PIPE thread, not 3/8 MACHINE thread

[donsladek]

FYI, Rodney Dickman has posted on his site that his business is for sale. He wishes to retire, and looks like he wants someone to continue the business:

https://rodneydickman.com/product_info.php?products_id=542

[donsladek]

More info on Rodney Dickman's business from a craigslist post by him:

https://chicago.craigslist.org/nch/bfd/d/caledonia-unique-auto-parts-business/7518482989.html

FYI, Rodney Dickman has posted on his site that his business is for sale. He wishes to retire, and looks like he wants someone to continue the business:

https://rodneydickman.com/product_info.php?products_id=542

[FunElan]

Seems like a cool business, if I knew anything about the rest of his market.

Is the idea with this fan switch that the fans come on at a lower temp? Seems like an easy investment to make

[Rambo]

Is the idea with this fan switch that the fans come on at a lower temp? Seems like an easy investment to make

Yes.

[exeterjeep]

Sorry to raise this on an old thread.

Coming back from a car show yesterday got a bit stuck in a bit of traffic on a dual carriageway, the temp went up to over 3/4 (almost half way between the 3/4 and top reading) before the fans came on. Was a bit of a worry.....

Is the lower temp fan switch still available from http://rodneydickman.com/product_info.p ... cts_id=444 as this says his store is for sale? and the best option available.
Thought I might order one of these??? Reading this topic there seems a choice of temp setting, Would the 200/210 be appropriate.

[chrism]

exeterjeep, your temp gauge seems as 'quirky' as everyone else's and certainly as bizarre as mine: The fans kicked in whilst stationary and 'out of the air, and that's the important bit.

If I recall correctly the m100 t/stat opens around 82C (180F) and the fans cut in around 107C (225F) the running temp will be around say 90 - 100C and the system is pressurised to cope with temps above 100C.

Your 185/195 switch is 85C/91C so your fan might well be running (almost) constantly - and the 200/210 switch is 93C/99C will be within the 'normal' running zone so might be running (quite a bit) more often.

I gather from a LEC pal (who was part of the m100 development team) that the m100 system passed numerous tests in US deserts - so it should easily have the capacity to cope in our very recent hot weather.

I have an adjustable therm. fan switch and I've adjusted it down from 107C to 104C and occasionally heard the fans in the very recent hot weather when putting it away in the garage after a run. I must admit (after previously owning an MGTF135, known for temp control problems) that it comforts me to know that they're still working when that gauge goes crazily high.

Only my opinion - and I hope others will correct me - that your Dickman switches might well be a bit of overkill for UK?

[RonR]

A while back the weirdness of the Temp Gauge was explained as a mismatch between the sender and the gauge, and I think it was there's only on f in Geof Smith who worked out a simple circuit to make it more like a "normal" car. I haven't tried it but the theory looks sound.

More info in the WIKI HERE (From the Wayback Machine)

[exeterjeep]

Now that summer is almost over and winter coming, think I will leave it until I next go down to SWLC and ask them for any advice. I see there are topics on having a fan override set up, so I'll ask about that as well. At least that might reduce my blood pressure readings in a similar situation.

[MPx]

Coming back from a car show yesterday got a bit stuck in a bit of traffic on a dual carriageway, the temp went up to over 3/4 (almost half way between the 3/4 and top reading) before the fans came on.

Sounds pretty normal to me Keith. Its rare that the engine gets hot enough for the fans to kick in while in normal use...the guage stays at about 1/4. But sometimes if I haven't used the car for a while I'll leave it idling for a while until the fans have cut in and out a couple of times. As long as they do...the guage is pretty irrelevant...but its showing around 3/4 when that happens.

[chrism]

Yep, totally aligned with MPx 1/4 and 3/4 readings...

[lotusflasherman]

This old chestnut again ? Way back, around 2015 from the date of the jpeg I created, I provided info about what the divisions on the temperature gauge relate to.. and to save people searching it seems appropriate to repost it here - Note that this relates to L100 ELN, there can be some variation between cars.

temp.jpg

Note that Lotus Service Notes KD1 (Engine Cooling System) states the header tank "is fitted with a 120 kPa (17.5 lb/in²) pressure cap to raise the boiling point of coolant to 131°C." , but Technical Data (TDH Page 5) states "110 kPa (15 lb/in²).

I use the higher pressure cap and a higher set engine thermostat (as used on a Vauxhall Astra diesel van), 88°C i.i.r.c. against the OE 85°C 'stat'.
My understanding of thermodynamics from over 50 years ago was, and still is, that best output is from cool, preferably damp, air going in to an engine as hot as possible.

I have no idea why anybody thought this mod' necessary, very rarely have my fans ever cut in, even when in 35°ambient in the south of France, and then it's only when stationary or 'crawling' in traffic, and they don't run for long before the temp gauge is back down and they're off again.

[TorqueHorse]

Figured I'd update this post in case others are consulting it for getting a new Fan Thermo temp switch. If you are planning to get one from Rodney, don't get the 185/195 one expecting a direct fit. The threads on that one are .3mm bigger in diameter.

As other folks have posted here that they've had good luck fitting his sensors in the past, I'll assume they got the 200/210 version (which also says it is 3/8 NPT in the listing, but I don't have in hand so can't verify).

To summarize, in case it isn't clear to others (like it wasn't to me at the time) both of the temp switches that Rodney sells are lower than the stock on/off points.

Per workshop manual and recent testing by folks the stock on/off points (in F) are 230/217

Not advocating for any one of these options, just updating to let people know what's up, if they are looking to buy one.