Re: Transmission top cap
Sorry for the delay. Needed to do some research??
The 200/250 are small bearing transmissions.
The 270/275/280/285/290 are the mid size bearing transmissions.
The C and later transmissions are large bearing.
Each Intermediate housing is machined accordingly, so the transmissions cannot be swapped between these three.
In other words, the 280 will not fit onto the 250 intermediate housing.
It's possible you may not even have a 250. You may have a later drive with a 250 shift cover on it.
The 250 is rather unique in that the intermediate housing has an oil fill port just above where the lower unit mates up to it.
The very first gen 270's also had this port......, so it can get tricky if you don't know how to tell the difference
Transmissions of like model numbers can be swapped, but only when re-shimming is done.
All lower units can be swapped when re-shimming is done.
The best bet may be to repair the 250 top cover.
Or, install the 280 transmission with the 280 intermediate housing.
If this is an early 280, the female yoke should be course spine, as is the 250.
The 280 may have the single pin for the 250 helmet.
The 280 suspension fork will allow the 280 intermediate to fit the 250 transom shield.
However, you need to re-shim the 250 lower unit to the 280 intermediate housing.
