Thermo Fan vs Viscous Fan v6.023.455

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Originally Posted by DoubleChevron

Where did you get the nice big rebuildable radiator ? :)

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An earthmoving radiator service company in Moorebank whom I have had a long-established customer relationship.

Superior Radiator Service and somewhere I have their number, let me know if you need.

It's based on the original tanks, but I had them remove the heat exchangers out of them, and the core is 4 row all-brass for heavy duty use (coastal area here). I've seen too many oil/coolant failures due to heat exchangers in radiator tanks, not worth the risk. Especially if you have a ZF box.
remote oil/trans coolers are cheap and effective and more importantly isolate their fluid from the cooling system.

In our climate, it's not absolutely necessary. There are advantages to the coolant/fluid heat exchangers, but the benefits are outweighed significantly by the consequences of a failure and the risk.

The oil filter cooler is easy, and the trans cooler lines need adapters to make it fit with ease, but all in all it's a better solution for a longterm owner.

Interesting reading Mercguy, re the failed fan.

I used to have lots of Rovers up to when I got my '79 RRC. Mainly P6s, but then started on SD1s too.
My first was a very ratty '76 model. Interesting departure from the luxurious P6 philosophy.
Anyhow, this '76 one day decided to go 'all diesel' on me. Out on a highway I forget, I hear a loud metallic thud, the receding tinkling of a metallic thing and then a diesel like vibration from the otherwise smooth V8.
Obviously had to pull up to check what the problem was, and as the V8 still had power, my initial thought of a piston having flown the coup couldn't be right.
Pulled up, and motor vibrating really really badly .. as said, not unlike a typical old school oiler. Switched off to see if anything obvious, but couldn't notice a thing.
Never thought that a metal fan blade would just come clean off so easily. Yeah this one had a 5 or 7(can't remember) bladed metal blade on the viscous. I do remember it was odd number tho.
Couldn't see it, till I closed the bonnet and noted a small dent from inside out. Oh!
Opened bonnet looked close at the area, and then saw that one of the blades was missing. Was obvious as anything having so few blades.
Reason I remember the odd number of blades was that I had to choose which blade to snap off to re balance the fan ... as best as possible.
Enny Meeny mynie mo did the trick. Blade levered back and forth and V8 pretty much smooth again. No other damage tho. Dodged that bullet having read your story. New fan found back at home and all good again.

Other worrying fan cracking issue I(we) had to deal with was brothers Patrol(4.8lt)
Over a Xmas/NY camping trip to the Murray, his Patrol started overheating, blew hoses etc. I traced it to a failed VC hub.
All we could do with the tools I had was to hand drill a couple of tek screws to get us up to the Murray, settle the families and deal with getting a VC hub for a Patrol up in Albury .. should be easy. No hope.
Went to Nissan, and a couple of other auto parts places, none in stock. For a Patrol .. in Patrol country!
But the real issue was his fan. Lots of stress fractures throughout the entire fan. And now locked up obviously a lot more likely to break.
So while in Albury we also got a lot of expoxy(some Selleys stuff, can't recall which one) and just basically glued it all up before it shattered to tiny bits.
Well, it kind of worked .. only in that it didn't break into thousands of shards .. but having let it dry for 2 days(we just chilled for the week), after the first run, all the epoxy we smeared over the fan just whizzed off in all directions.

Quote:

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Originally Posted by DoubleChevron

Where did you get the nice big rebuildable radiator ? :)

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There's Bendigo Radiators too.
Back in the early-mid 90's when I needed a rad for my '79, I thought of using him to rebuild mine, quote was about $900 or so.
But I also think that included an external oil cooler as well(maybe).
At the time I was mates with Tim at Roverdrive, and he found me an all copper std rad for under $200 .. so of course I went with that instead.

Not exactly sure what he charges now, (about 3-4 years ago now) I think he said $700 for a four core(rebuild of your own) for a Tdi rad.
Tdi rad is 3/4 the width of the V8.

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Originally Posted by DoubleChevron

You should be running full speed (I'd hope). With series/parallel, slow speed is the fan wired in series ... so each fan gets 6volts, and if there is any wiring/fan issues, you will have no fans. Parallel is high speed, ie: 12volts to each fan. wiring or fan issues should leave the other fan working too :)

The falcon fans may have had a resistor there for low speed? I bypassed this though and wired myself.

seeya,
Shane L.

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Phil's nice thermo set up got me looking at what's around as controllers these days.

I'm still happy with how it works the way I did it originally about 20 years ago but I wonder if the fan in mine that is on all the time only runs on 6V.

The other fan is switched by an adjustable temp sender in the top radiator hose that cost more than Phil's Davies Craig unit back in the day and has no read out.

Someone sent me or posted a wiring diagram for the EL fans (which are unique I've found out) with the series parallel system that gives the 2 speeds.

Any chance that could be posted again if the author is reading this?

Here's a great vid of a Ford Fairlane V8 that gets converted from viscous to the twin thermo set up............talks about current draw of the Ford fans as well.

https://youtu.be/A96ej_NQkKo'si=qkja9mVvIRmIvedz

cheers, DL

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Originally Posted by 350RRC

Phil's nice thermo set up got me looking at what's around as controllers these days.

I'm still happy with how it works the way I did it originally about 20 years ago but I wonder if the fan in mine that is on all the time only runs on 6V.

The other fan is switched by an adjustable temp sender in the top radiator hose that cost more than Phil's Davies Craig unit back in the day and has no read out.

Someone sent me or posted a wiring diagram for the EL fans (which are unique I've found out) with the series parallel system that gives the 2 speeds.

Any chance that could be posted again if the author is reading this?

Here's a great vid of a Ford Fairlane V8 that gets converted from viscous to the twin thermo set up............talks about current draw of the Ford fans as well.

https://youtu.be/A96ej_NQkKo'si=qkja9mVvIRmIvedz

cheers, DL

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quick 30second google search. You just need three standard automotive relays. Use a big fuse, not self reseting circuit breakers (been bitten there, in heavy traffic towing, the damn relay derates massively leaving you with no fans working ... :o ).

Just a moment...

its uploaded ot a commodore forum

Attachment 194262

anyway, this looks good, and just google series parallel fan circuit images. Any standard high/low switch will work. I just unscrewed the single speed switch and screwed in a high/low switch that was in one of my old parts cars.

if you follow that through, you can trace out how simple and genius it is. a few wires, 3 relays from a parts car and you have a permenant high and low speed fan solution with no electronics to fail [bigrolf]

Oh, I just noticed, rather than running 12volts through the fan switch I switched the earths.... same thing, but I feel a bit safer, if the wires running across the engine ever rub through, you will just end up with your fans running

seeya
Shane L.

Thanks Shane.

The wiring that came with the new non-genuine fans in the shroud is as follows:

Fan 1......... on all the time ignition is on... white (+) and black (-).& red at the plug.

Red not connected to anything upstream..

Fan 2......... switched by adjustable temp switch....1 blue (+) at the plug and black (-) at the plug.

Another black and blue not connected to anything upstream of the plug

For some reason I snipped one of each on the second fan at the plug when I put them in, umpteen years ago and the red wire going to fan 1 is not connected to anything.

Each runs on a separate relay and they share a 50 amp fuse.

I know they're 4 pole motors and I'm now thinking they're only running on 2 each. Your thoughts?

Probably were installed about 25 years ago and work fine.

David L

Quote:

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Originally Posted by 350RRC

Thanks Shane.

The wiring that came with the new non-genuine fans in the shroud is as follows:

Fan 1......... on all the time ignition is on... white (+) and black (-).& red at the plug.

Red not connected to anything upstream..

Fan 2......... switched by adjustable temp switch....1 blue (+) at the plug and black (-) at the plug.

Another black and blue not connected to anything upstream of the plug

For some reason I snipped one of each on the second fan at the plug when I put them in, umpteen years ago and the red wire going to fan 1 is not connected to anything.

Each runs on a separate relay and they share a 50 amp fuse.

I know they're 4 pole motors and I'm now thinking they're only running on 2 each. Your thoughts?

Probably were installed about 25 years ago and work fine.

David L

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There might be a low speed resister in the standard wiring. I just snipped the wiring off and directly wired the motors. You will know if you have it wrong as the fans will spin backwards [bigrolf] So each fan ... two wires ... can't really get it wrong :)

Thanks again Shane.

I'm now thinking that what I already have has worked fine for a long period of time and there's not much to gain by making it more complicated.

The only issue was a long time ago when fan 1 stopped working and I installed another motor from a genuine shroud and all was good.

I opened up the dud motor and the brushes had slightly seized. Works perfectly now, so it's a spare.

This was on the fan that's on all the time and the brushes were hardly worn.

David L