Fan woes

[dykins]

On my way to a car show this morning, I heard a loud, sudden grating noise from under the bonnet

 

It would appear that a large stone has bent one of the blades on the original four blade fan, and this was then catching on the rear of the radiator.

 

I was able to bend the fan blade back to something close to normal and fortunately there appears to be no leaks from the radiator. I was then able to drive slowly home.

 

Am I right in saying that a new (or secondhand) fan needs to be dampened with a half-moon shaped washer? How easy is that to get right?

 

Could I fit a later TR6 plastic fan instead?

 

Any advice welcome.

 

Regards

 

Peter

[4Mal]

Hi Peter,

Not sure about the washer, but I might have an orginal fam around here somewhere. Let me know if you want me to go hunting in the garage.

[Chris59]

Peter,

 

Don't forget that it must be dynamically balanced .

 

I have used, on a TR4, an alloy extension from a TR4Airs + TR6 blue plastic fan, adaptation between the 2 parts was made using a machined alloy block.

 

Lighter and more efficient than the old cast iron extension + bend 4 blades fan

 

Chris.

[RAHTR4]

Peter,

 

Sorry and surprised to hear of your problem.

 

That must have been a shot in a million for the stone to pass through the grille without hitting any of the slats and then to hit one of the fan blades.......!!!

 

With the velocity involved it seems that if it had missed the fan blade as well - it would definitely have punctured the radiator.

 

Anyway, you can fit a TR6 yellow 8 bladed fan - providing that you use the shorter fan extension and fixing bolt from a Side Screen car to get the required clearance between the fan and the radiator.

 

Regards, Richard

[shroptr]

h peter will pop another fan up to monday night, i have fitted spitfire 8 blade plastic fans to 2 of our TR's on the original extention, done sweden,denmark lemans ect ect with no problems at all

 

simon

[dykins]

Thanks for the advice.

 

It looks as though Mr Beresford will come to my rescue (again!)

 

Richard - I actually don't know what caused the fan blade to bend. I assumed it must have been a stone or something, as there was nothing obviously wrong when I checked under the bonnet prior to my journey.

 

Thanks again

 

Peter

[stuart]

Thanks for the advice.

 

It looks as though Mr Beresford will come to my rescue (again!)

 

Richard - I actually don't know what caused the fan blade to bend. I assumed it must have been a stone or something, as there was nothing obviously wrong when I checked under the bonnet prior to my journey.

 

Thanks again

 

Peter

 

It could well have bounced up from underneath hence why it missed the rad and just caught the fan. Thats another reason why Triumph went to plastic fans as they are less susceptible to bending from impacts.(and cheaper )

Stuart.

[gnotte]

 

Anyway, you can fit a TR6 yellow 8 bladed fan - providing that you use the shorter fan extension and fixing bolt from a Side Screen car to get the required clearance between the fan and the radiator.

 

Regards, Richard

 

 

 

Hi Richard,

please do you know from which car make the shorter fan extension is coming ?

Thanks, Guy

[RAHTR4]

Hi Richard,

please do you know from which car make the shorter fan extension is coming ?

Thanks, Guy

 

 

Guy,

 

All TR2 to TR3A’s were fitted with a shorter fan extension part 108493 – 3.3/4” long overall.

 

This also requires a shorter fixing bolt, part number 108498.

 

Regards, Richard

[RAHTR4]

h peter will pop another fan up to monday night, i have fitted spitfire 8 blade plastic fans to 2 of our TR's on the original extention, done sweden,denmark lemans ect ect with no problems at all

 

simon

 

 

Hi Simon,

 

Interesting to learn about the fitting of a fan off a Spitfire - any chance of more details.

 

I have looked at Moss and Rimmers websites and they only show a 7 bladed plastic fan (part number RKC 2126) plus it does not have the rubber bushes and steel sleeves like the TR fitment.

 

I can see from the diagram that the centre boss of the fan is offset in the opposite direction to the TR6 fan - which I presume is why it must give the required clearance to the radiator using the original TR4 fan extension.

 

Is this the fan you have used?

 

Also have you modified it to fit the TR type rubber bushes and steel sleeves?

 

Regards, Richard

[shroptr]

hi just had a look at the spitfire fan and yes its got 7 blades (don't know where i got 9 from) basicaly the holes are in the right place just smaller so need to drill out and refit the rubbers and metal sleves from the existing metal fan into the new holes and fit to you original long extention ,it is not as wide as the plastic TR6 fan so plenty of clearance , took about half an hour to drill out and fix , we have done this mod to 3 of our TR's aftre 2 of them a 3a and a tr4 shed a metal fan blade each at speed not a pleasant expereince

the tr4 was on the m25 on our way to the euro meet in belgium , a realy bad virbration from fron of engine rigth to the back of the gearbox, after hacksawing the oposing blade off in Dover we then went on to do the euro meeting to spa and back, with no major prob at all, hopefully a pic of the spitfire fan on our tr4

 

cheers simon

[RAHTR4]

hi just had a look at the spitfire fan and yes its got 7 blades (don't know where i got 9 from) basicaly the holes are in the right place just smaller so need to drill out and refit the rubbers and metal sleves from the existing metal fan into the new holes and fit to you original long extention ,it is not as wide as the plastic TR6 fan so plenty of clearance , took about half an hour to drill out and fix , we have done this mod to 3 of our TR's aftre 2 of them a 3a and a tr4 shed a metal fan blade each at speed not a pleasant expereince

the tr4 was on the m25 on our way to the euro meet in belgium , a realy bad virbration from fron of engine rigth to the back of the gearbox, after hacksawing the oposing blade off in Dover we then went on to do the euro meeting to spa and back, with no major prob at all, hopefully a pic of the spitfire fan on our tr4

 

cheers simon

 

 

Simon,

 

Thanks for the insight - this has to be a good option with less parts to change..........!!!

 

From your photo I can see that the fan centre is the opposite way round to the TR6 fan, so this and a narrower unit give a good clearance to the face of the radiator.

 

Regards, Richard