PINION SHAFT AND SHIFTER FORK CRANK CHANGES
On the 741 engines starting with the numbers GDA-32037, the flywheel pinion shafts and pinion gears were changed from a straight shaft and gear press fit assembly to a tapered shaft and gear assembly.
The following parts were affected in this change:
| OLD TYPE | NEW TYPE | ||
| 39348 – | Pinion Shaft | (1936 to 1941 0 45″ – 30.50″) | changed to 44287 |
| 20B104 – | Pinion Gear | (1936 to 1941 – 45″ – 30.50″) | changed to 44288 |
| 37550 – | Washer | (1936 to 1941 – All Twins) | changed to 37855 |
| 37350 – | Washer Nut | (1936 to 1941 – All Twins | changed to 37856 |
When the pinion shaft (44287) has to be replaced and you find that the new type isn’t available, you may use the old type pinion shaft (39348) but will also have to use the old type pinion gear, washer and nut. The same proves true if it is necessary to replace the new type pinion gear and it is not available, in which case you would have to use the old type pinion shaft, washer and nut.
On 741 engines starting with numbers GDA-32037, the transmission shifter fork crank and shifter fork crank lever were changed from a key type shaft assembly to a serrated type shaft assembly.
The following parts were affected in this change:
| KEY TYPE | SERRATED TYPE | ||
| 44369 – | Shifter Fork Crank | (741 models only) | changed to 44845 |
| 43824 – | Shifter Fork Crank Lever | (741 models only) | changed to 44846 |
When replacing either one of these parts, it will be necessary to mate together the two parts according to the type of shaft assemblies, using a key type lever with a key type crank and a serrated type lever with a serrated type crank.
GENERATOR BELT PART NO. 42603
Because it was impossible for the belt manufacturers to supply us with the same belt we used on 340, 341 and 342
models, we are assembling on new 344 machines and supplying on parts orders a substitute belt (under the same
part number) which is one inch smaller in circumference.
When this substitute belt is used on 340, 341, and 342 machines you will find that the generator bracket cannot be lowered enough to get the proper belt adjustment (1/21″ movement up and down). However, by cutting 1/4″ from
the generator bracket adjusting screw, it can be turned farther into the bracket, allowing the generator to be
lowered enough to obtain the correct belt adjustment.
On 344 machines, the diameter of the generator driving pulley was changed from 2-7/8″ diameter to 2-5/8″ diameter
to allow for the use of this smaller belt; however, a number of 344 machines were shipped before this change went into effect.
When it is found that the generator belt is too tight on the 344 machines, check the diameter of the generator drive
pulley. If it is the old pulley (2-7/8″ diameter), write in to the Service Department for the correct pulley (Part No. 50186, 2-5/8″ diameter). When ordering this pulley, give the engine number of the 344 machine on which it is to be installed.
It is very IMPORTANT that this condition be taken care of because a tight belt wears out fast and also decreases the
life of the generator drive sprocket and armature bearings.
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