The flywheels look similar to the A10 ones, they look quite light to me.

these are my engines, definately j15's...

First engine.
























Second engine.
























Third engine.

have a look in my photos, there afew of different angles of a J15, the most obvious difference being the row of visible head studs along the side of the rocker cover(above the spark plugs).

austins and MG type A or J series like motors also have cast iron heads be careful as you dont want those boat anchors.

Thanks Dodgeman

I was looking at the 3 j15s advertised on ebay. They look like A15s to me. Shows you how much I know

Cheers

racnod

A bit like night & day really, but if the small pushrod engine has an external aluminium oil pump, on the right side of the block near the front, driven by a horizontal shaft, then chances are that it's an A series engine.

If it looks like an Austin A40 engine, if it has a cast iron head, then it's probably a J series engine.

An examination of the engine number will reveal all. These two Datsun engines have the engine letter code & the engine capacity code as a prefix to the engine number.

Can anyone tell me the difference between a J15 and an A15 engine?