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RMB Fan Belt Removal

At first sight removal of the main fan belt looks a bit daunting and the instructions in the Workshop Manaul and the Driver’s Handbook do not give much useful help to a new owner either. The procedures for belt removal are similar for both the RMB and RMB2 (often called the RMF engine) although the RMB2 is simpler as it does not have a separate fan assembly and hence has only one belt. We will therefore concentrate on the RMB engine.

It is always a good idea to get as much working space as possible so if your car is one of the later ones with removable side panels, remove the one on the carburettor side.  If your car is an earlier one with fixed side panel access will be a bit cramped.

 

The first thing to be done is to remove the small fan belt. This can be done by loosening the clamp bolt and turning the fan assembly to its highest position using a rod inserted into one of the holes as shown. The belt can then be lifted off the pump pulley.

 

To make access easier while the main belt is being pulled out or replaced the whole of the fan assembly can be removed by undoing the clamping bolt completely, taking it out and then pulling the assembly forward and lifting it out of the car. If for any reason it is stuck and will not pull forward, the four screws holding the clamping bracket to the engine mounting plate can be removed and the clamp bracket complete with the fan assembly can be lifted out.

As can be seen from the above picture the main belt which drives the dynamo and the water pump, passes between the engine and the front engine mounting plate and is effectively trapped there by the engine mounting bolts on either side.  One way to release the belt from this trap is to support the engine from beneath using a jack and a load spreader under the sump while the bolts are removed. An easier way is to remove just one bolt at a time, slip the belt past where it was, replace the bolt and then remove the second bolt making sure to replace it once the belt has passed all the way through. This is how we will do it.

We now need to remove the main belt from its pulleys. Slacken the screw holding the  adjuster arm to the dynamo and push the dynamo as close to the engine at it will go. You may get it to move a little closer if the screw is removed completely. The dynamo may be very difficult to move in which case the two bolts holding the dynamo to its mounting brackets underneath will need to be slackened off. These are difficult to reach especially if the side panels cannot be removed.

With the dynamo pushed in as far it will go to give as much slack in the belt as possible the belt can be lifted off the dynamo pulley. This may not be as easy as it sounds as the belt may still be quite tight. Owners of RMB2 engines may be lucky and the dynamo may be fitted with a split pulley. Removing the nut holding the pulley to the dynamo will allow the pulley to split and the front side can be lifted away thus releasing the belt. Owners without a split pulley will have to “shoe horn” the belt off the pulley. This can be done by pulling the belt over the edge of the pulley while the engine is turned with the starting handle.  DO NOT PULL THE BELT WITH YOUR FINGERS. If your fingers get trapped  between the belt and the pulley a very painful injury will result.  Instead lever the belt off the side of the pulley with a screw driver as the engine is turned.  During this process the screw driver will itself get trapped between the belt and the pulley and will start to rotate with the pulley. Do not hold the screw driver while this is happening or your hand may get trapped between the screw driver and the engine compartment side.

With the belt off the pulleys we now need to get it past the engine mounting bolts marked as “A” in the picture opposite.  Remove the bolt and spacer nearest to the dynamo. Push the belt past the now empty mounting hole and replace the spacer and the mounting bolt doing the bolt up tight.  With the engine safely secured again, remove the other bolt and the spacer and pull out the belt making sure it has been taken off the crank shaft pulley.

As they say in all the best manuals, reassembly is a reverse of the above procedure.

Once again you may need to “shoe horn” the belt onto the dynamo pulley after it has been fitted to the water pump and crank shaft pulleys. Finally retension the belt by pulling the dynamo outwards and retightening the adjuster clamp screw.  Make sure all bolts are properly tightened and the small fan belt is also retensioned.