• If you like antique engines, vintage tractors or old iron machinery, register and join us. When you register on Smokstak, please give complete answers and fill in the blanks. - IF YOU ARE ON WIRELESS OR SATELLITE, ENTER YOUR CITY AND STATE! NO ZIPCODES! All registrations are manually approved.

Odd OA Bagshaw Governor


I was in the process of assessing what bits I could utilise off a parts OA Bashaw I have, for the build of a couple others. Anyway I hadn't taken much notice of this engine previously, it was basically bought for the original carby and then chucked up in the pallet racks out the way. So while looking it over I noticed that the governor is a bit different to normal as shown in the pics.
Generally the normal Bagshaw governor utilises 2 linked weights fitted to the cam gear which rides on a solid shaft as shown in Pic 1. Speed is controlled by moving the small lever from notch to notch in one of the weights thereby adjusting the spring tension. This requires stopping the engine as this is all behind the flywheel
As can be seen in the 3 remaining pictures this governor in question has been modified (or set from factory?) with only 1 weight, which has had the link rod recess filled with lead. Also the shaft has been drilled and a rod fitted which actuates a pivot setup. The rod has a small chain fitted in the inside and by pulling on this it would control governor spring tension by pulling the rod back against the pivot. This rod consequently looks to be made from a cut down buffer rod that fits inside the atmospheric inlet valve of these engines and helps prevent valve flutter when the exhaust is locked out on the miss cycles. This modification looks to have been very well done and not just a farm fix looking at it.
One advantage I can see with this setup is the speed can be adjusted without stopping the engine and that rather than 5 preset speeds/notches being available it can be varied to any speed between min and max movement of the pivot.
The other oddity with this engine is that instead of having a pulley fitted it has a belt groove machined in the off side flywheel, something I haven't seen on any other OA Bagshaw engines. Pictures in next post.
So the question is has anyone seen a similar set up OA Bagshaw or have any idea what it may have been used to drive that required the modifications?