mickmini wrote:
you were working on those engines from the 30s to the 70s
I know diesel is a lube for some engines - like two stroke diesels. you don't have to add two stroke oil to the diesel for those, unlike a two stroke petrol engine
I worked on the Comet engines and transmission in the mid 60s during my apprenticeship. It had 4 Detroit Diesel 6/110s in the power car, coupled to 2 transmissions.
I also worked on the later railcars which had 6/71 Detroit diesels.
BTW, 2 stroke GM diesels (like these) have oil in the sump and a normal lube system, they don't draw a charge into the crankcase like petrol 2 strokes do:
There's a row of inlet ports right around each of the cylinders at BDC, these are fed air from a Rootes type blower at about 3psi. The 4 exhaust valves are in the head, and all open together.
So, it works like this- the ex valves open before BDC on the power stroke, the incoming air scavenges the exhaust gases up and out the exhaust valves, which shut just before the air ports are covered. So cylinder is now full of air.
Then just before TDC (on compression stroke) the fuel is injected, ignites and the power stroke begins.
Back in the 60's a 6 litre 2 stroke diesel had the same power as a 12 litre 4 stroke one (without a turbo). It was also half the size and weight.
<edit> Later Detroit Diesels had a turbocharger as well as the blower...

_________________
DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.
