COOLING FAN RUBBING

[Tim Ward]

hello every one

My cooling fan seems to occasionally rub on my upgraded rad.

There does not seem to be any play in the coupling, and it operates normally.

I assume that the fan blades have lost their rigidity

A new fan is £ 60 , so before I brought one I would welcome other members experinces to see if a new fan would solve the problem.

PS could some one tell me the gap between the blades and the rad? Its a MK2



Thanks Tim

[stagstr]

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Hi Tim,

Also check that the viscous coupling is shearing because if it isn't then it could be the force applied to the blades at speeds it wasn't meant to go at, that's bending them. Also check that the engine mounts are OK because the collision with the radcould be happening under braking, when the lump goes forward as the nose drops.

How far away from the rad is the crankshaft bolt?

Ray

[Kevin Garrod]

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Hi, its a bit tricky to measure the gap between the bolt and rad, but between the leading edge of the fan blade and rad on mine I have approx 33mm hope that helps.

[Tim Ward]

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Ray

Thanks for thoughts

I seem to remember breaking hard from speed, when somebody pulled out

Tim

[Tim Ward]

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kevin

Thanks I will measure mine

Tim

[NickA]

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Tim Ward wrote:

hello every one

My cooling fan seems to occasionally rub on my upgraded rad.

There does not seem to be any play in the coupling, and it operates normally.

I assume that the fan blades have lost their rigidity

A new fan is £ 60 , so before I brought one I would welcome other members experinces to see if a new fan would solve the problem.

PS could some one tell me the gap between the blades and the rad? Its a MK2



Thanks Tim

If it's an upgraded rad the gap will be much smaller than with a standard rad. Mines 18mm. I can't change the fan belt with the rad in as the gap between the front bolt and the rad's only 5mm.

Nick

[Chris810]

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If the viscous coupling is not viscing ( slipping ) properly then as mentioned before the fan blades will rotate at too high a speed and bend forward touching the rad, this is more common with the uprated rad as the gap between the blades and the rad is much smaller than normal, my experience with uprated rads is that mine actually made it run hotter ( something to do with the more restricted airflow I suspect )

I now usea standard radiator and backflush the rad and the block using the two blanking plugs on the side of the block ( clear out the holes with welding wire first ) every 2 years

Works for me

[Tim Ward]

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Chris



Thanks for your thoughts, it might be better to do away with fan and fit an electric

one



Tim

[Tim Ward]

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Kevin



Measured mine its a lot less than 33 mm, I assume because I have a larger rad

I am off to the Devon rally this weekend so I can look at other peoples.



Tim

[Tim Ward]

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Nick



My gaps the same, do you have marks on your rad ?

Tim

[NickA]

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Tim Ward wrote:

Nick



My gaps the same, do you have marks on your rad ?

Tim

Nope, no marks at all. [1]

Where are the marks on the Rad, do they form a circle or in just one area? If they're just in one area I'd vote for weak engine mounts, PITA to swap with the manifolds in place!

Nick

[1] apart from where the pully nut came loose and went throught the centre of the rad but that's a different story.

[Tim Ward]

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Nick



Thanks, I think I will swap the mounts

Tim

[DJT]

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Tim Ward wrote:

I am off to the Devon rally this weekend so I can look at other peoples.

Tim,

Hope you enjoy it. Weather not looking too great, but fingers crossed...........

I was going (paid up months ago) but my employers transferred me to another location and I can't get cover, so I am stranded on a North Sea Oil production platform 90 miles NE of Shetland rather than enjoying a wonderful day in my native Devon with over 100 classic cars :X:X:X:X

Dave

[stagstr]

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Hi Tim,

I just looked at my rad gap as I have had the same problem, because my rad is 'uprated' too. Surprise, surprise my figures are the same as Nick's and I too cannot get the fan belt off between the bolt and the rad. I seem to remember Nick and I had an email exchange on the Stag Digest about whether it is possible to put the front engine mounts on the wrong side of the chassis member and thereby bring the engine too far forward. We decided it isn't.

My rad used to be marked at various points by the sweep of the blades and also oppposite the bolt.Two or three years ago I took the rad out, straightened all the fins and painted it so that I could see what, if anything was stillhitting it. (I bought the car with the marks on but was not hearing or seeing any collision so I didn't know if the previous owner had fixed it).

Some time later the marks were back again but I hadn't heard anything, nor was it visibly happening when theengine was idling. Because the bolt had made a mark it was clear the engine was moving forward and I decided that the viscous coupling was OK, so went down the engine mount route. The rear mounts, at the back of the gearbox, were very soft indeed, probably softened by the oil that's leaking out! So I replaced these first - quite a simple and inexpensive job.

Bingo, that fixed it so I didn't bother with the very awkward-to get-atfront mounts. Touch wood, all is still OK. So Tim, if you want to start with the cheap and simple then do the rear mounts first.

I hope this helps

Ray

[Tim Ward]

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Ray



Thanks for reply.

The thought process you have gone through was the same as mine.

I was going to repaint the rad and watch, but after a trip to the east coast I noticed new marks

I checked my engine mounts last night, and they seemed ok. Also I was thinking of changing my gearbox mounts, because of sloppyness when taking up drive.



Thanks again I will let you know



Tim