Morris Minor Owners Club

I'm looking for the differences between the marina 1300 engine and the ital 1300, I think I have an ital, but as the pistons have 4 rings I'm not too sure. Can anyone list the changes please?

Nothing too important - why does it matter to you ?

Well I'm that sort of guy Roy!! but the main reason is the question regarding piston rings, I'm surprised to find my motor has 4 the ital usually has 3

Could be aftermarket pistons I suppose - does the block have liners fitted ? I'm more 'up' with Mini engine variations - not sure how much that carried through to the in-line engines. Is the 4th ring below the gudgeon pin ??

Standard bore, no liners all rings above pin. Hope this is pretty common as I want to get some new rings before assembly.

basically the ital engine has a ribbed block and the dizzy is held in place with a fork arrangement

It likely does have dead standard pistons - just ask the suppliers of the new rings. So the Ital block pretty much equates to the later A+ Mini blocks - except for the (silly) high mounted oil filter of course....... Q for you though - are the cap side main bearings completely plain surfaced - with the block side having a central oil groove ? And -is the block above the central main bearing completely solid - or does it have a casting hole through the web?

The mains cap has the groove, same as the block. You may be thinking of the metro turbo which has the solid cap bearing.
There is no hole above the centre web. I may need a piston set rather than just rings; the top compression groove may have too much play, I've not measured it yet but may play safe anyway.

Thanks Les - it was indeed the Turbo that started the plain bearing trend in Mini engines - but it was such a success it was soon rolled out on ALL Mini/Metro 1275 blocks - just wondered if it had spread to the Ital block too. It is possible to fit these better bearings - you just need to file/machine the little notch to take the tang on the bearing shell. If buying pistons - may as well get a rebore and then it will be 'like new'.....

I think the ital may have ended before this plain shell was started, however interesting to hear it was adopted elsewhere and if possible to retro fit, maybe an idea.
I am rather disappointed at the possibility of needing new pistons, as suprisingly the bore diameter at the top is only 2.5 thou more than at the bottom, which is standard, but if I need pistons, yes, a rebore makes sense.

None of the Ital A+ engines would have 4 ring pistons, they all used the 3 ring design. You also shouldn't have the casting window in a Marina or Ital engine. This was only present in some Midget engines and those without the window are very desireable. The pistons are probably a hepolite item so rings shouldn't be a problem to obtain.

That was my original doubt, but as the pistons are standard and I'm sure leyland items, the mystery remains.

the marina engine (early ones at least) had 3 comp & 1 oil ring . I'm running Ital engines in my cars The one on std bore has 2 comp & 1 oil.
also one has the grooved mains where the other has plain mains plus other little differences like drilling's for a direct bolt on alternator (like a maestro) & the block drain bung deleted

Thanks for that, any more subtle differences you know, please post. The block I have is ribbed which I took to be an ital, do you know if marinas had A+ blocks?

Interesting to hear there are 'plain' main bearings in some NS engines - thanks for that!

Hi Les,
Did you ever get to the bottom of this? I have exactly the same situation, thought I had an Ital engine to rebuild but it also has 3 rings plus the oil ring. Need to purchase new rings but not quite sure what I need or where to get them.

Well my project has not progressed very far, even after all this time! However I have bought new pistons and they have 4 rings, as the original ones have. It’s an A+ ribbed block, I’m taking it as from an Ital. The bore is standard.

Mine is also ribbed and standard, the rocker cover has an A+ sticker on it. Odd that the Ital workshop manual has 3 rings while the marina one has 4. Will keep looking for the rings but may need to purchase new pistons as you have. Thank you for the reply.

The only differences I am aware of between the pre 'A' Plus engine block and the 'A' Plus engine block is the way the distributer is secured and the additional ribbing on the outside of the block.

Except for the distributer and distributer drive all parts are interchangeable between pre 'A' Plus and 'A' Plus engines.

Some 1275cc Marina/Ital blocks have the window above the centre main and some do not.

The fitment of three rings was a later development to the 1275cc 'A' Plus engine.

It is perfectly feasible to fit only three piston rings to four piston ring pistons.

Use the top two grooves for the compression rings and use the bottom groove for the multi-part oil control rings.

Below is a picture of four ring pistons/rods I removed from a Marina/Ital 1275cc 'A' Plus engine.

les wrote: ↑Sat Jul 23, 2011 9:31 pm Thanks for that, any more subtle differences you know, please post. The block I have is ribbed which I took to be an ital, do you know if marinas had A+ blocks?

Eight years late with the reply:-
There was a transitional period.
My engine came out of a Marina Mk3, it has the ribbed block, single bolt U clamp distributor fixing, twin branch exhaust manifold, points ignition I think A+ was electronic, rear crank scroll seal (see question below) and a blue 'A' without the plus sign on the rocker cover. Also this engine's head was painted red then over painted black at the factory.

A question, I was told by the previous owner that the Ital A+ engine had a rear main lip seal factory fitted, is this correct?
Regards John