Morris Minor Owners Club

I thought the 803 had a cast iron water pump - whereas the 948 had an alloy version, and the two were not interchangeable - or have I got this wrong? Anyone?

Both are cast iron - and they are not interchangeable....... Later trade replacement water pumps for A series engines are in aluminium alloy usually. But they don't fit the 803 engine. Not sure what it would take to modify one to fit though!

Later replacement pumps often don't always fit the 948 either... although they should.

One guy I know had to trim the blades to get it al the way into the block That was on a pump supplied in 2011.

Thanks for that guys. I'm having a bit of dificulty identifying engines. I think I have an 803 currently fitted and have just got hold of a 948 to replace it. What suprises me is that they both look identical, cast iron water pump, same looking joined manifold. Both have lost their engine numbers (must admit it was a bit daft to put the numbers on a riveted on plate!) I just want to make sure that my 803 isnt actually already a 948. Apart from measureing the bore / stroke - is there another way to confirm the engine as an 803? The new lump must be correct as it has '950' in large numerals on the front N/S of the block. Any help greatly appreciated.

Yes -there are two sizes of trade pump - the large impeller is for the 1275 engine, the small for the 948/1098 engines.

Have a look at the timing chain cover. The 948 will have teeth at the bottom for timing marks, the 803 has an arrow impressed into the metal. Unless someone has changed covers at some stage of course......

Oil filter housing would have been different on the 803 also.
As far as I know, all 948 will have the "950" cast into the block.

Unmistakeable difference. The 803 has a canister oil filter screwed into the side of the block