Morris Minor Owners Club

hi all bad day . can some one help i have been sorting out rebuilding my 1275 as i think the 1098 in my traveller is on its last legs (pushing it too fast again ) the problem is that i have just put all the bottom back together . and got to the head , i have put the push rods in and the tappets on but either teh push rods are too short or teh tappets are to big. i am trying to use 1098 as a temp messure so that i can save up for the stronger ones . now can any one tell me if the 1098 ones will fit on the 1275 are thay the same size and lengh .thanks
mm16

If its a Marina type 1275 without side plates , the cam followers are a totaly different type ( known as mushroom) and are fitted from the sum side before you fit the camshaft.

Oops that should read SUMP side

No - the cam followers are exactly the same ! Been eating mushrooms maybe ??
However - the 1098 (and 948) push rods are a good bit shorter than the 1275 pushrods - it has a longer block and so needs longer pushrods. They are no 'stronger' - just longer.

aren't the valves different lengths too?

I've got a 1275 valve and what i think is a 948 valve on my desk and i'd say there is a good 4-5mm difference in length.

Yes - the valves in the 1275 type 12g940 head are longer too. I assume though that mm16 is NOT trying to use a 1098 head on a 1275 - because that will not work.

well its from a mg its red that is all i know about it . right thanks all for the info .the head is from that engine its a 12 unleaded so that side is fine just need to get hold of some 1275 push rods can any one help me there
mm16

if it is from an MG are you sure it is an A series engine?? could be a B series, which are quite different...

I assume MG Metro !! Why did your 1275 engine not have push rods ?

well the flywheel has 6 bolts , a breather on the front of timming chain cover ,the head fits the 1098 , rocker cover is the same,exhaulst manifold is the same ,the bottom pully dose not have the starter handle bit on it ,sump is the same ,but i can not tell you if its a b ser but looks like a ser as looks the same as the mini and the morris minor one

If the head fits on the 1098 - it's an A series. You might want to fit the starting handle dog from the 1098. Note also this engine is 3/8" taller - so your exhaust manifold will sit that 3/8" higher. Hope there is clearance.

well it came with the head and rocker cover and that was it ,no tappets nor push rods do not know were thay went

When you say 'tappets' - do you mean rocker gear - or cam followers ? The 1098 rocker gear will not line up with the 1275 valve centres. You can re-aligne them on the shaft - need some washers and a bit of filing - or chase up a set of 1275 rockers. the later sintered rockers that were fitted to Mini engines have big wide rockers which straddle across the valves on 1275 engines. They are not much use for 'competition' - but fine on a road engine.

the later sintered rockers that were fitted to Mini engines have big wide rockers which straddle across the valves on 1275 engines. They are not much use for 'competition' - but fine on a road engine.

They come in vary handy when on a 1098... then you can swap between 12G940 and std heads without worrying about rockers.

right thanks for that so if i get mg 1275 rockers that will be fine and will help in a bit of speed and then get some push rods

if its a rear drive 1275 from an MG chances are its from a Midget

right thanks for that so if i get mg 1275 rockers that will be fine and will help in a bit of speed and then get some push rods

I don't think they will help wih speed, but should remove the alignment problems. If you can find the 'billet' rockers as used on the late Mini 1275 GT etc.. they can be used on any A-series (unless you want a racing engine, as they are heavier and not as strong as competition rockers)