It was my engine that knackered out through lack of oil as the main reason. I have finally stopped kicking myself, beind a time served mechanical fitter, it shouldnt have happened. As John has stated I do not own a Hydramaster TM, but it could happen to any TM if theres not enough oil in the engine. Oil does seem to an issue with Briggs engines though, or is it just with mine.
The reason the oil was on the low side was because a few times I ended up over filling it - filled to correct level on dipstick, only to discover later that oil was slowly still finding its way to the crankcase. Contacted suppliers about this and was told the the engines have a very slow fill and empty. For this reason, when checking iol level, I wasnt too concerned if it was a bit on the low side, but obviously I allowed it to get too low.
After I did the first oil change on my new engine after 8 hours running time, I drained it whilst still hot. I then duly added the 1.6 litres fresh oil. Problems arrose again and I had to drain off half a litre to stop it being sucked up and choking the carb. Even though I left it half an hour to drain further after the flow had apparently finished, there must have still been half a litre somewhere in the system. The oil filter is only small and can not hold anywhere near that.
Incidently the manual gives the low oil shut down switch as an option, so will not be (as in my case) be fitted as standard in all cases.
Dave.