Modified MGB 7 Blade fan

The MGB 7 blade fan requires 4 extra sleeves in the mounting holes to centre it on the MG TD and TF models using the original bolts. The standard fan mounting holes are all different in size due to the pressing. This fan is lighter than the original MG T-Series fan and operates far more efficiently to improve cooling.

It has been known that the original metal fans disintegrate due to metal fatigue with disastrous consequences.

Fig 1 – MGB 7 blade fan.

Fig 2 – Sleeved MGB 7 blade fan.

Fitting can be a nightmare – be prepared! It’s all very tight space in there but can be done with a little patience without removing the radiator. Proceed as follows:

Tape a thin sheet of cardboard on the inside of the radiator to save your knuckles. Remove the old fan blades using a 9mm 1/4″ drive socket and clean off everything.

The spacer flange which accepts the fan can rotate relative to its threaded back plate by a few mm. Fit a bolt first to align the holes and mark this position (flange/backplate) with an indelible pen for each of the four holes. This is very important as it can be very frustrating when you try to fit the fan and find that the bolts will not push through into the back plate and the bolt will not want to engage in the threads. You could clamp this position using a hose clip. Remember you have to rotate the flange to fit each bolt in turn and this tends to draw the holes out of alignment.

The fan can only fit one way round to avoid a clash with the thermostat elbow – this will be obvious. Photo 3 shows the side of the fan which goes on the flange. The clearance between the centre flange on the fan and the radiator is only 40mm so you may need a mirror to help fit the bolts as you cannot see the heads. Get each bolt started before you tighten it up.

I have attached another photo (Photo 4) of my installation for reference.

Fig 3 – Showing the side of the fan which goes on the flange.

Fig 4 – Another photo showing the installation in Declan’s TD.

Declan Burns
Liedberger Weg 6A
40547 Düsseldorf
Tel +49 211 371529 after 5pm.
Email : declan_burns@web.de
Note: declan underscore burns at web dot de

5 thoughts on “Modified MGB 7 Blade fan

  1. James Thomas says:

    I fitted one of these on my MPJG TA with no modifications and it is significantly better than the original. They look better if painted black imo.

  2. Rod Schweiger says:

    I have had these yellow plastic fans on my 1966 MkIII Sprite and seen many on MGBs descentrigate with age and heat. If you use one, be prepared to inspect and replace when necessary. I’ll stick with the factory one on my TD thanks.

  3. Ron Benson says:

    Be warned! I did the same mod on my TB and as the blades flex slightly when revving the engine, one got behind the cross brace and cut the radiator core! This cost me a re-cored radiator. I had to refit it with a Wolseley 4/44 pulley which is shorter.

  4. Geoffrey Glasson says:

    There are “two” MGB yellow plastic fans, the only one that will fit the TD is the Moss #434-340. I’m yet to fit mine & as Declan stated the holes don’t line up properly, but I will work around that.

  5. Bill Worden says:

    Thanks for great article Declan.

    Reaming to 7.7mm for a 7.0 bush is a lot more clearance than usual for a bushing. Is this to facilitate fitting?

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