Service, Overhaul intervals for WW2 aircraft engines question.

[MiTasol]

6) I would say not, the power egg was not a universal 'thing' I don't think, most aircraft engines are a big job to change as a lot is 'built around it' - its a great idea, four bolts, two control connections and a few hoses sounds wonderful - I wish the aircraft I look after had that!

Mitsubishi Mu2 -- The cowls, three bolts, two cannon plugs. two fuel lines, two control links and the starter/generator cables and it all comes free. I have removed them in as little as 20 minutes but we did one almost every weekend so had more than a little practice. The same engine in a G1000 took a full day to change and sometimes you would damage the exhaust seal so have to do it again. @#$%^&*

Worst I have worked on was the Bristol Freighter. Removing the "egg" took relatively little time but getting the engine out of the powerplant took four people four or five days from memory. Putting the unit back together took weeks. Getting the cowls off took a day on its own as all the nuts were hard to access and turn (not anchor nuts) and the screws were difficult to access because one person had to hold the cowl at a particular angle which made holding the screwdriver difficult while stopping the screws from turning. It would have taken one person under an hour if anchor nuts were used.

P-40 is easy, Mustang far from. On all engines radiators, oil tanks and oil coolers should be changed (or at least removed and power flushed) in case there are metal particles in them.
I have seen more than one idiot change a sick engine only to have the new one fail within hours because the old one had left metal in the oil tank and cooler and that chewed up the oil pump and bearings. Never saw the same with the glycol system but it was possible and the particles would probably damage the pump fairly quickly.

 

[bdefen]

1) I would say there would be too many differences between these engines to give a meaningful answer. You have air cooled radials and liquid cooled in-line engines listed here - wildly different in operation. Suffice to say, each aeroplane fitted with a certain engine would have a fixed schedule of maintenance (if it survived that long - most did not!).
2) Again, every aeroplane would have its own list of items that needed to be completed in a turn around, some lists were no doubt added to, or reduced, based on experience in the field.
3) Tune ups were not carried out as far as I know, you had routine maintenance at the fixed interval but everything else was not interfered with unless disturbed in the course of other work. For example the valve clearances and magneto timing on the P&W Wasp Junior (R985) are not altered between overhaul (unless necessary).
4) Each engine had its own TBO or Time Between Overhauls. In the case of Russian engines these were only noted in the first engine log and set by the factory dependant on the aircraft to which the engine was being fitted so the same ASh-82FN engine might easily have different TBOs depending on its fitment.
5) If the pilot or flight engineer noted a large lack of performance and there was no control or accessory issue, the engine would be changed, same if it used unusually large amounts of oil and there were no obvious leaks, there were not too many other ways of telling!
6) I would say not, the power egg was not a universal 'thing' I don't think, most aircraft engines are a big job to change as a lot is 'built around it' - its a great idea, four bolts, two control connections and a few hoses sounds wonderful - I wish the aircraft I look after had that!

Thank you!