Viscous coupling or electric fan?

[Bazstag]

The bloody couplings failed again after only 800 miles, even though i'm trying to keep the car as original as i can i,m thinking of fitting an electric fan,Dont want to be forking out £70 every 6months or so on something thats got build quality issues.

[V Mad]

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They are normally reliable. Where did you buy it? Did you get the right one for your fan(there are two different fans each with a differentviscous coupling)?

[Lytham Stag]

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Well I removed the viscous couplingand fan last year and rely on the electric fan only. So far so good.

[Bazstag]

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V Mad wrote:

They are normally reliable. Where did you buy it? Did you get the right one for your fan (there are two different fans each with a differentviscous coupling)?

This is the 2nd one in a year, admittedly the first one was exchanged free from JP's but 7 months down the line i dont think he'll do it again, as discussed on the forum last year there were a few people who had troubles with their new couplings. Mines a mk2 and there was no probs with fitting.

Baz

[V Mad]

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There are two points here:

1. JPs are a good supplier, and I am sure they will not want their reputation tarnished by an unreliable part, and will gladly refund or replace it. They will want to return it to their supplier for investigation/refund, and should result in this part either being improved, or discontinued.

2. Sale of goods act entitles you to a part which isfit for purpose, and of merchantable quality. Its not your fault the part has failed, so the law is on your side.

Stick to your guns and good luck with it.

PS: you could go with just an electric fan, but these alonecannot provide the level of cooling under certain very high demand conditions(high load, or long uphill mountain runs in hot weather), and they can fail too!

[Bazstag]

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V Mad wrote:

There are two points here:

1. JPs are a good supplier, and I am sure they will not want their reputation tarnished by an unreliable part, and will gladly refund or replace it. They will want to return it to their supplier for investigation/refund, and should result in this part either being improved, or discontinued.

2. Sale of goods act entitles you to a part which isfit for purpose, and of merchantable quality. Its not your fault the part has failed, so the law is on your side.

Stick to your guns and good luck with it.

PS: you could go with just an electric fan, but these alonecannot provide the level of cooling under certain very high demand conditions (high load, or long uphill mountain runs in hot weather), and they can fail too!

Thanks for the reply, i've just been reading up in the 'search' and as you've stated some people have had problems with high temperatures under the bonnet(hot wires,fuel boiling/vapourisation etc)lights dimming when using an electric fan. As i've had no problems in the past with any of these conditions i might try with a new coupling and will let you know the outcome with JP

Baz

[DJT]

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Hi Baz,

I am one of those that suffered 'premature coupling failure' last year and got a free replacement from JP. So far so good with the new one, but it hasn't done that many miles yet. I shall wait with interest how you get on. If mine fails again I shall probably go down the electric fan route and hope to get a good discount from JP in exchange for the failed viscous.

Dave

[comeinhandy]

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I installed an electric fan complete with plastic cowling from a volvo 340 that was in my local scrap yard. It is a very powerful 2 speed one. It works a treat.And is built to be reliable (productioon standard).

(I also built my own electronic temperature control with two identical circuits driving the twofan circuits for different temperature settings on each oneand so that each acts as a backup for the other in case of failure. Also an additional circuit to keep the temperature controller powered for 5 miniutes after the engine has stopped, prevents any 'heat soak' that can cause poor hot starting on some engines due to fuel boiling in the carb.)

[Kevin Garrod]

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Welcome to the forum, and we're going to need to see some pictures!

[Bob Heritage]

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Baz,

There have been some dodgy couplings around for the last 18 months, seems you have had two of them, if it was me I would send it back again.

[Mark S]

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Hi Baz,

I've never had a mechanical fan, mainly becauseit was missing when I bought the car. I have a powerful electric unit from a Senatormounted in front of the rad controlled by an otter switch in the rad. It only ever comes on around town or a while after coming to a standstill. I've run this set-up for the last five years without any problems with overhearting, vapourisation, hot starting etc.

I picked up aused fan / viscous a few months ago that I'll be fitting before Spring in addition though because I like the idea of a steady waft of air around the engine at all times.

I don't believe that the mechanical fan delivers sufficient coolingat tickover and the electric fan performsin spadeswhen it's needed, soI still wouldn't rely on the mechanical fan alone.

Mark.

[comeinhandy]

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Attached is a pic of an electricfan from a scrap volvo 340 fitted in my stag in front of the rad, complete with cowling that forces the air over the whole rad. Very powerful. A cheap and I consider better alternative than aftermarket fans. I use no mechanical fan. It is of great benefit to have the controller powered up for 5 mins after the ignition is off to avoid heat soak and fuel boiling in the carb.

[mjheathcote]

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comeinhandy wrote:

Attached is a pic of an electricfan from a scrap volvo 340 fitted in my stag in front of the rad, complete with cowling that forces the air over the whole rad. Very powerful. A cheap and I consider better alternative than aftermarket fans. I use no mechanical fan. It is of great benefit to have the controller powered up for 5 mins after the ignition is off to avoid heat soak and fuel boiling in the carb.

Sorry, don't like the look of that at all for one simple reason, it must surely be designed to be mounted behind the radiator, not in front:?

When mounted behind the radiator, the whole radiator matrix is exposed to the in coming air flow, and once the air has passed through the matrix is free to pass out of the cowling.

Presently you only have the diameter of the fan open to the incoming air flow reducing the surface area of the radiator matrix exposed to cooling incoming air.

Can't believe that works effectively.

[Mark S]

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I'm afraid I agree, it looks like a pull fan, it'll not work efficiently running backwards and that cowl will severely inhibit ram air. Does it run constantly?

The fan I use is a push fan with a ring cowell from an air con system. It has only five blades and doesn't seem to inhibit air flow too much.

Mark.

[Bazstag]

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Bob Heritage wrote:

Baz,

There have been some dodgy couplings around for the last 18 months, seems you have had two of them, if it was me I would send it back again.

Got an email back from Jp's today stating,

"Very odd,can you assemble all of your component parts in the sequence they are fitted and take a picture,pointless for both of us if i replace and it fails soon afterwards".

Luckily i have'nt taken it off yet so i'll take some pictures of it, possibly video it moving, i did'nt think you could assemble it wrongly as long as you've got the spigot on etc. On a positive side thoughI'm glad the couplings gone now and not 2 months down the line as the car is going for its mot tomorrow and the tax runs out at the end of the month(i'll sorn for a couple of months).My plan is to put it on stands to drop the subframe and change the seals on the diff',so if there's a bad outcome on the mot i'll sort that out, plus it'll get its yearly flush,oil change etc

Baz