Fan Belt

[JFerg]

In twenty years of 4A ownership, I'm sure I've changed a few fan belts, but today I'm in strife.

 

Whilst out, the 4A threw its fan belt. No worries, I have a spare. If only I could get it on.....

 

The clearance between the fan extension and the main cross member of the steering unit is only 2mm. The belt itself is 11mm thick.

 

I've tried lifting the engine on the mounts to see if that will give me some clearance, but it won't give me enough. Now I have the radiator and cowl out, with a view to pulling the fan extension off in the morning. All to fit a fan belt? I sense that I am doing something wrong here, or am at least missing a fundamental point. What is it?

 

Obviously I am yet to inspect the (aluminium) fan extension, but to get 11mm clearance I'd have to machine an unreasonable 18mm off it's diameter, so don't see that as a solution. Is there a steel (?) after market extension?

 

I'm running an aluminium radiator and an electric fan, but retain the original fan because I understand that it is also the harmonic balancer. So what have I done wrong here?

 

thanks in advance....

 

JFerg

[RogerH]

Hi, (what does the |'J' stand for)

 

the engine is almost certainly collapsing the engine mounts - replace with Land Rover parts - have a look here - www.johnrichardssurplus.co.uk

These are similar to TR4 mounts but better.

 

You could simply undo the engine mount nuts - this would allow the engine to raise slightly.

 

You can put spacers under the engine mounts to give better clearance.

 

When you have fitted the belt consider fitting another one that is tied out of the way for a quick fit if needed.

 

The fan needs to be balanced but is not really a harmonic balancer for the crank. I would remove it unless you do a lot of slow heavy traffic motoring.

 

Roger

[JFerg]

Thanks, Roger.

 

Since posting earlier I have been into my books. The workshop manual is silent on clearances and fan belt changes, but Roger Williams' "How to restore Triumph TR4 and TR4A" refers to a minimum of clearance between fan extension and rack, and the need to lift the engine for a belt change, so I am not entirely alone. However, when lifting the engine until the wheels came up, I still had insufficient clearance.

 

I'd already planned to tie a spare belt in there, and I'll do that. I'll also have a look at the front engine mounts; but since they didn't stretch to give me clearance, I suspect that they're ok. Or just wrong completely.....

 

thanks for your valuable inputs, Roger. It really helps.

 

cheers,

 

John Ferguson

[peejay4A]

You'll need to slacken the engine mount nuts as well. Whilst your at it why not replace the mounts with the LR ones as Roger suggests?

[stuart]

Make sure the engine mounts if they are the later 4a type are fitted in the right orientation as I came across one the other day with the mounts aligned horizontally which 1 would not allow the engine to be jacked up at all and 2 if they failed would allow the engine to slide forwards or backwards with dire results!

Stuart.

[ChrisR-4A]

I would not disturb the fan extension unless you intend to ditch it and get a narrow belt conversion with a damped pulley. I have run like this for over 15 years and electric fan hardly ever comes on.

Rather than removing the extension of you want to refit the wide belt do as suggested else where and remove the engine mount nuts to allow it to lift.

[TR 2100]

Make sure the engine mounts if they are the later 4a type are fitted in the right orientation as I came across one the other day with the mounts aligned horizontally which 1 would not allow the engine to be jacked up at all and 2 if they failed would allow the engine to slide forwards or backwards with dire results!

Stuart.

 

Having never owned a TR4A, I was not aware of that one.

Very clever of the factory.

 

Almost as clever as making an exhaust manifold gasket

that can be fitted 90º out, thereby significantly reducing

the exhaust flow.

 

AlanR

[Geko]

While replacing the engine mounts years ago, I added a 4mm shim on either side in order to increase the clearance between the fan extension and the steering rack. I did succeed to remove the fan belt once (with a bit of pushing/pulling) with that system but i'm afraid that now that the mounts have settled down it wont be possible anymore. I believe that in doubling that thickness it should no problem.

[stuart]

 

Having never owned a TR4A, I was not aware of that one.

Very clever of the factory.

 

Almost as clever as making an exhaust manifold gasket

that can be fitted 90º out, thereby significantly reducing

the exhaust flow.

 

AlanR

They were known as "Fail safe mountings" Which if fitted the right way is true if not......................

Stuart.

[BlueTR3A-5EKT]

Hi, (what does the |'J' stand for)

 

the engine is almost certainly collapsing the engine mounts - replace with Land Rover parts - have a look here - www.johnrichardssurplus.co.uk

These are similar to TR4 mounts but better.

 

You could simply undo the engine mount nuts - this would allow the engine to raise slightly.

 

You can put spacers under the engine mounts to give better clearance.

 

When you have fitted the belt consider fitting another one that is tied out of the way for a quick fit if needed.

 

The fan needs to be balanced but is not really a harmonic balancer for the crank. I would remove it unless you do a lot of slow heavy traffic motoring.

 

Roger

Land Rover Nos either NRC2053 or NRC2054 they are both the same thickness but different external diameters. And have metric threads....

 

Peter W

 

PS I am not sure what NTC5890 is as far as dimensions compared to TR4/4A engine mounts. Worth 2 quid to check it out I guess.

Edited April 18, 2016 by BlueTR3A-5EKT

[RogerH]

8mm I think.

 

 

Roger

[Rob Salisbury]

A trick here is to fit two fan belts at the same time, wrap the second belt in cling film and cable tie it to the engine front plate (looped behind the front pulley) so it's ready to slip in place when your newly replaced fan belt gives up the ghost, the ones available these days really don't seem to last very long.

Cheers Rob

[rcreweread]

Hi, (what does the |'J' stand for)

 

the engine is almost certainly collapsing the engine mounts - replace with Land Rover parts - have a look here - www.johnrichardssurplus.co.uk

These are similar to TR4 mounts but better.

 

Roger

Roger

 

John Richards lists 2 engine mountings - do you know which is the right/best one please - NRC 2054 is 55mm in diameter and 32mm thick, and NTC 5890 is 75mm in diameter and 37mm thick.

 

The larger sounds like it should be better but don't want to create other problems unknowingly - really good price at £2.00 each!

 

Cheers

 

Rich

[RogerH]

Hi Rich,

I got the 2054 and seems to work well.

 

As mentioned above they do have 8mm stud. This is not a problem.

 

Roger

[rcreweread]

Hi Rich,

I got the 2054 and seems to work well.

 

As mentioned above they do have 8mm stud. This is not a problem.

 

Roger

Roger

 

You have a PM

 

Rich

[Fireman049]

Thankfully, my 3A came already fitted with the narrow belt conversion ~ Highly recommended.

 

Tom.

 

 

Edited April 20, 2016 by Fireman049

[nigethomas]

fitted a new belt on my 4a a few week back and had same problem.

Just slackened off the engine mount nuts enough to jack car up

and then slide past.

 

Nige

[lynchpin]

Hi

As Nige above says I fitted a new belt some weeks ago simply loosened the near side engine mount top nut wood under sump and jacked up engine no probs..

 

Phil..

[Fireman049]

Jacking up engines just to change a fanbelt ~ No thank you folks.

 

Tom.