The first task was a detailed inspection to assess the condition of the engine and to establish what, if any, parts were missing. The main mechanical problems which were identified were:- 1. Badly bent Crankshaft - The crankshaft was badly bent on one side resulting in a flywheel wobble of approximately 2". As the bend started immediately after the main bearing it can only be assumed that the engine was dropped from a height causing the crankshaft end or flywheel to hit the ground and the resultant impact has bent the shaft. It is highly likely this happened when the engine was dragged out of its place of work prior to being recovered by the previous owner. 2. Cracked Cylinder Liner and Piston Skirt - The cylinder has a 1" hairline crack running from the outer edge at the bottom of the cylinder and the piston has a similar crack in the same location running from the edge of the skirt. This has probably been caused by a careless past owner who has disconnected the con-rod from the crankshaft and allowed it to drop with the con-rod striking the inner edge of the piston/cylinder resulting in the crack.
3. Broken Air Valve Assembly - The air inlet valve/fuel mixer which ultimately controls the speed of the engine via the governor was badly damaged. It appears to have been sawn through on one side and bent/snapped on the other side. This was a major issue as successful repair of the original would be very difficult due to the precision nature of this part. As parts are unavailable further investigation would be required to determine the route for repair/replacement.
4. Missing Piston Rings - Only one plain piston ring came with the engine, 3 were missing. Although not a huge problem to overcome as piston rings can be purchased specially made it was still another issue that had to be resolved.
5. Cylinder Wear - It was noted from visual inspection that the cylinder had a noticeable wear lip internally which would be an issue in relation to obtaining new piston rings and ensuring good compression was maintained.
6. Damage to Cylinder Head Casting - Damage was noted on one of the flanges for the inlet valve assembly. This would have to be repaired to ensure a good mechanical seal was maintained.
The main parts which were deemed to be missing were:-
General observations:- 1. Cylinder Oiler - Rather than the normal drip feed oiler screwed directly into the top of the cylinder, this engine has been supplied with a remote oiler and pump system bolted to the main engine casting. The pump is a plunger type operated from the exhaust valve level and operates by pumping the oil which collects in the pump reservoir to the cylinder via a copper pipe. The copper oil feed pipe screws into the same location as where a drip oiler would traditionally be found. This is either a design modification by Petters or a specification change by a customer. The oiler capacity is no more than a normal oiler therefore the only reason that this remote arrangement was used coule be to allow longer running periods by preventing the heat from the engine thinning the oil excessively and thus increasing the drip rate. By having the oiler remote the oil heat up as much compared to being directly above the hot cylinder if running for excessively long periods. We would certainly welcome any additional thoughts on this change. 2. Paintwork & Lining - This engine has 90% of the original paintwork, lining and transfer intact which gives the engine a superb period look. The engine will certainly not be repainted, where required the paint will be preserved and parts such as the cylinder head will be given a coat of matt finish black VHT paint. The transfer on the cylinder is still quite legible but has suffered a little more than the rest of the engine due to surface corrosion. As the whole engine had been given a coat of good quality varnish by the previous owner this will have helped stabilise and preserve the transfer. The transfer depicts the XXXXXXXXXXXXXXXX.
Petters used a range of detailed tranfers on their earlier engines as per the example below which shows the 'Five Horses' Transfer on the base of early M type two stroke engine.
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