Fans and viscous couplings used on the Stag

[sujitroy]

A Stag buddy of mine here in in USA gave me his viscous coupling and fan off his Mk2 factory AC Stag. I have a couple of fans and couplings and put a video together of my findings and observations. Comments welcome.

https://youtu.be/iqHCmL-Ewck

[STypeR]

Nice video sujitroy. Good to see the different couplings and a steel fan. I didn't realise the factory AC had the steel fan, probably for greater airflow as it had to pull air through the now vertically mounted condenser. I wonder if the Mark I with AC which had the condenser mounted low between the chassis rails had the same steel fan?
Here, even in 100 degree plus days (40 degrees Celsius) mine never overheated with a dealer fitted serpentine condenser in front of the radiator and that's with the standard plastic fan and no shroud, hilarious!
I've since managed to mount a modern 'parallel flow' condenser in the Mark I position; freeing up the radiator.
I actually ditched the factory fan for a USA made 16" pusher. I don't like the viscous set up where at idle (when you need max airflow) the engine's only doing c750RPM and at high speed where you need no fan assistance the fan's doing c2000RPM...

[trunt]

Just to throw another variable into the mix…
When I got my Mk2 federal with a/c car it had no engine however it did come with a block and crankshaft, plus a harmonic balancer with a third type of pulley mounted on it. It was not the short nose like the mk1 or the long nose like the mk2. It had a long nose like a mk2 but without the turned end. There was no viscous or fan so not sure what it mated to!

picture below.. its on the left. on the right is the Mk1 pulley, the viscous is mk1 as well.

engine9.JPG

[STypeR]

Yes, that's an odd pulley that third one you mention. Has to be the power steering pulley but who knows what viscous fitted that?

[trunt]

Yes, that's an odd pulley that third one you mention. Has to be the power steering pulley but who knows what viscous fitted that?

My guess would be that metal fan/viscous Sujit has???

It exists no longer.. I had it turned down to a Mk1 type as mine was so rusty and I had the viscous/fan for that.... in the end I went full electric

[STypeR]

Yes, you're likely right its for the metal fan. Good idea to turn it down.
What electric set up did you do, and did you end up putting in A/C?

[mole42]

I don't like the viscous set up where at idle (when you need max airflow) the engine's only doing c750RPM and at high speed where you need no fan assistance the fan's doing c2000RPM...

The purpose of the viscous coupling is to prevent the fan rotating at engine speed when it's at high RPM. At idle, full power is delivered to the fan, at high RPM the coupling slips reducing the power transmitted, so the fan isn't rotating at the speed of the engine. Hence the manufacturer's name for this device "Torquatrol".

[trunt]

Yes, you're likely right its for the metal fan. Good idea to turn it down.
What electric set up did you do, and did you end up putting in A/C?

I always kept the option open for A/C and made sure the heater box was ready but in the end decided not to go ahead.

I have the Davis Craig EP setup so that controls the fan. The relay and fuse are in an auxiliary box along with the headlight relays. It’s a 16” pusher.

[jbuckl]

sng barrett offer the viscous coupling in 2 ‘levels’ of quality.

[sujitroy]

Nice video sujitroy. Good to see the different couplings and a steel fan. I didn't realise the factory AC had the steel fan, probably for greater airflow as it had to pull air through the now vertically mounted condenser. I wonder if the Mark I with AC which had the condenser mounted low between the chassis rails had the same steel fan?
Here, even in 100 degree plus days (40 degrees Celsius) mine never overheated with a dealer fitted serpentine condenser in front of the radiator and that's with the standard plastic fan and no shroud, hilarious!
I've since managed to mount a modern 'parallel flow' condenser in the Mark I position; freeing up the radiator.
I actually ditched the factory fan for a USA made 16" pusher. I don't like the viscous set up where at idle (when you need max airflow) the engine's only doing c750RPM and at high speed where you need no fan assistance the fan's doing c2000RPM...

My May '71 Mk1 AC fitted stag had the condenser mounted vertically in front of the radiator. It has a plastic Mk1 fan and Mk1 coupling. I have a Mk2 parts car which also had the condenser mounted vertically in front of the radiator. I'm not 100% sure about the metal fan being fitted only to car which originally came with AC, but I did ask around and it seemed plausible.
Sujit

[STypeR]

My May '71 Mk1 AC fitted stag had the condenser mounted vertically in front of the radiator. It has a plastic Mk1 fan and Mk1 coupling. I have a Mk2 parts car which also had the condenser mounted vertically in front of the radiator. I'm not 100% sure about the metal fan being fitted only to car which originally came with AC, but I did ask around and it seemed plausible.
Sujit

The factory must have changed the condenser mounting position and the fans from pullers to pushers earlier that what I thought. It was a curious move.
The engineers would have a good reason to place the condenser away from the radiator in the first place; you would think to give the radiator maximum airflow, definitely a clever idea.
Parts Catalogue shows the change from LF10004 and LE11277U onwards.