1-1/2 HP Bates & Edmonds Bull Dog restoration, Part 2

A Bull Dog gets its bark back


| December/January 2008


Editor’s note: The following is Part 2 of a four-part series on Peter Rooke’s restoration of a 1-1/2 HP Bates & Edmonds Bull Dog.

Pouring the bearings

Before starting to pour the bearings, all bearing areas on the main casting were brushed and cleaned with emery cloth to remove all traces of rust, in order to improve adhesion. In particular, the recesses were cleaned out to keep the bearings in position. Fortunately, I possessed some formers from another bearing repair that would fit this job. They consisted of a central core (some 0.100 inch smaller than the crankshaft diameter) and two recessed end caps. These end caps had supports to keep the caps aligned in the bearing recess.

The formers were coated in oil to prevent the white metal from sticking to them then clamped in position. When white metal cools it forms a curved rather than level surface, which can drop below the required line at the edges. To prevent this, a small dam was built using babbitt putty, thus increasing the height of the white metal poured. It was also necessary to seal the gaps between the edge of the formers and the engine casting to prevent the poured metal from leaking out. (If you use fire clay rather than babbitt putty, it is essential to ensure it is fully dried when pre-heating the casting or else you will run the risk of the molten metal spitting back if it hits any moisture).

On a cautionary note, adequate safety precautions are always essential when heating white metal: safety glasses, trousers, long-sleeve shirts, preferably an apron and leather gloves. The white metal was heated in a pot, stirring from the bottom with a thin pine stick to keep the alloy fully mixed. With a low tin, white metal is at pouring temperature when the pine stick starts to singe after being held in the metal for 3 or 4 seconds. When the metal reached pouring temperature, the mold and casting were heated with a gas torch to preheat it and stop the white metal from cooling too quickly and cracking when it hits a cooler casting.






SUBSCRIBE TO GAS ENGINE MAGAZINE TODAY!

Gas Engine Magazine A_M 16Gas Engine Magazine is your best source for tractor and stationary gas engine information.  Subscribe and connect with more than 23,000 other gas engine collectors and build your knowledge, share your passion and search for parts, in the publication written by and for gas engine enthusiasts! Gas Engine Magazine brings you: restoration stories, company histories, and technical advice. Plus our Flywheel Forum column helps answer your engine inquiries!

Be sure to take advantage of the Square Deal Subscription Program.

  • No Missed Issues.

  • No Renewal Notices.

  • No Additional Cost.

The Square Deal Subscription Program is designed as a paperless transaction with automatic renewals at a preferred low rate.   With advanced electronic notification, a 100% satisfaction guarantee and an easy opt-out plan, the Square Deal Subscription Program is the best value, risk free, eco-friendliest way to subscribe.




Facebook YouTube


Copyright 2018, All Rights Reserved
Ogden Publications, Inc., 1503 SW 42nd St., Topeka, Kansas 66609-1265