WOTSIT NO.1

Here's the engine as we found it.

 

In an effort to restore this engine to its former unknown glory and hopefully aid us in identifying it we have dismantled it for inspection and repair.

 

O.K. so a fair amount of work needed here so we'll start with refurbishing the crankcase and go from there. I think that we will abandon the idea of keeping the plain bearing main journal in preference for converting this engine to a twin ball raced crankshaft. We will achieve this goal by remachining the case main diameter out to 28mm diameter to accept a 12 x 28 x 7 ball bearing and a pressed in front bearing housing to hold a 9 x 17 x 5 front bearing.

O.K. so the first step in our repair/transformation in bringing this engine back to life is to start with the basic crankcase.

 

First step, remove the brass plain bearing bush from the aluminium crankcase casting.

Next stage is to mount the raw case up into our machine and re machine the crankcase inside dimensions to allow the fitting of the new rear ball bearing and the pressed in front bearing housing.

Here we have the main case all finished and ready for the front bearing housing to be pressed in.

Next step is machine up the front bearing housing and then press it into the main case.

O.K. so here's the new front bearing housing we've made all sorted and ready to press into the crankcase, thus completing our conversion to TBR for this engine.

And fitted.........

Next step is to remachine the intake port hole into the new front bearing housing and while we've got it all set up in the milling machine to do that we will finish off the machining of the rest of the venturi part of the job, enlarging the intake hole and creating an angle on the inside of the venturi, clean up the N.V.A. faces and lastly square off the end of the venturi and apply some roundness to the intake edges.

O.K. so, crankcase is finally all finished and ready for the other bits. Next mission, crankshaft.

 

One crankshaft coming up.