Lund's MG Metro 1275 Engine Build

[Mini_Lund]

Hi all,

I now have an A+ MG 1275, a Metro 1275, and a 998! The MG metro comes with all ancillaries electronic ignition, HiF44 cone filter etc etc, but is without a gearbox. However, the Leyland 1275 has a gearbox but no diff. The 998 has a diff, but the engine isnt in good health! So, I intend to use the box off the 1275 and the 998 diff - will the box mate to a A+ MG block? Also, will the diff suffice and take the power of the MG 1275, which I hear is 72bph @ 6000rpm as standard

The MG metro also has a high lift cam and was rolling roaded before it was removed from a Mini, due to gearbox problems. It has covered approximately 55,000 miles in total. However, the cam is unknown, but I was told that it idled smoothly and ran sweetly.

I'm wanting to spec the engine for acceleration more than top-end speed.

What sort of power output will I be looking at with an MG Metro 1275, electronic ignition, MG alloy inlet, HiF44 carb with K&N, Cooper freeflow exhaust, with straight through Rc40?

One other question: Can I legally use my straight though RC40 exhaust with this engine? Or do I require a CAT?

Many thanks,

Tom

Edited by Mini_Lund on Thursday 15th January 20:48

[Mini_Lund]

PJR said:

I don't see why you'd need to add a cat? And it's really not something you want to have on a Mini anyway.

Depending on what the condition of the engine is like, and how well it's been set up, I guess you could expect 75-85bhp or so. Might not sound like loads, but it will likely be more than double what the 850 donk put out on a good day, and will drive light-years better

Gearboxes were never my bag though! So i'll let someone else advise you there Although you may have problems with the diffless 1275 box if it doesn't include the diff case/casting.

P,

Ah, silly question on my behalf! CAT's wernt introduced until the early 90's. Well thats good news. As for the gearbox, you're right, the 1275 has no diff or diff casing, but the 998 does - I intend to use that. I essentially have 3 engines to make one unit. 4 if you include the 850

Tom

[Mini_Lund]

Hey, I'm currently battling my dad for space in the garage, as his Mk111 is in there.

I have just noticed that the box on the 1275, is an A+ Metro box. Therefore the transfer case will fit the MG block and the CWP's and drop gears will fit! Which I'm more than happy about. I was told that the cam was a high lift cam, but was'nt always hunting. The cam profile is still unknow to me - any easy way of finding out?

[Mini_Lund]

minimatt1967 said:

not with out taking the cam out and checking the serial number!

Ah right, didnt think it was easy...

Thanks...


bad timess bad timesss

[Mini_Lund]

I wont quote the post, but thank you very much Peter, your advice is always clear and definitive!

Well, I haven't aquired any of the engines yet as I'm battling my dad for garage space. I'm losing! I hope I can persuade him somehow or another. I'm sick to my back teeth of the 850. I'd rather spend money on a larger bore unit for more gains and driveability.

[Mini_Lund]

Finally aquired the engines, so I can begin cracking on with the engine build. Will be building up a 1275. It apparently already has a fast road cam in, but we'll see! Watch this space!

[Mini_Lund]

minimadmotorman said:

Are those bronze valve guides I spy? If so it's possible that the cylinder head has had some modification in the past.

Good luck!

I doubt it, but I hope your right! I cannot for the life of me, get the cyldiner head off the MG, I have managed to undo all of the head bolts, but the head will not shift. I have hit it with a rubber mallet several times to no avail. I even resorted to the butane flame, but still to no avail. I have sprayed WD all around the outer edge of the head and block, but it just wont come free! Suggestions?

Its difficult to do anything when the engines sitting on its crank! I don't fancy getting the box off the Metro just yet either!

There is no engine number, the only part numbers I can see are that on the block face and on the crank itself, if I can get the crank number, will it tell you guys anything?

[Mini_Lund]

Cooperman said:

Put the plugs back in and turn it over with a long bar on the crank pulley bolt. The compressions may, just may, free it off. If not, you will have to use brute force!
Once in bits, check the case hardening on the cam lobes. It it's at all pitted, get another cam. Hardening is better these days, but a few years ago it was very poor.

Great idea, however, I'll have to tip the engine its side to do so! I spy bronze valve guides also Stuff like this never happens to me, so I'm made-up! Excuse the poor pic's;

[Mini_Lund]

The head didnt come off with the compression alone I can't think what to try next?

Crank: 12G1433 - CAM 6328













Any Ideas?

Edited by Mini_Lund on Friday 16th January 14:14

[Mini_Lund]

minimadmotorman said:

Take the water pump off and give it a good whack from the underside with a wooden/rubber mallet.

Those deffo look like bronze valve guides to me. any chance of some more pics of the inlet/exhaust ports on the cylinder head. might give a clue to if its been ported.

The head hasnt been ported I don't think, as the castings are still visible on the inlets and the exhaust ports are tiny. I'll get the water pump off asap - I used a scissor jack to pry the head from the block, but to remove the head it must come off flat and not as an angle. It does wiggle about abit, but not enough to get and lift off. Im aching all over, thats me done for today!

[Mini_Lund]

minimadmotorman said:

Head has probably just had a recon then.

Yeah thats most likely. I managed to pry the head from the block on one side with the scissor jack, however it needs to be removed flat otherwise it wont come off. I got the straw on the WD and sprayed all between the block and the head, so that should free things up abit. I think the head studs are snagging the head therefore not pulling off. I've even had the engine upside down, hitting the head with a rubber mallet...no avail! I put the plugs back in and turned the engine over, hoping the compression would blow the head through the roof, but...no avail. I suspect the head has had a recon as the bronze valve guides suggest this. I think I'll be taking a dremel to the ports like I did on the 850.

[Mini_Lund]

GTRMikie said:

Have you tried removing the head studs, then removing the head?

Thats exactly my next step, however Im worried about snapping the studs in the block. I do have spares, but its a case of where and how they snap if they do... worth the risk?

[Mini_Lund]

Managed to get the head off. The central head bolt is actually rusted onto the 'sleeve' if you like , of the cylinder head i.e the stud has been removed from the block but is stuck in the head. I removed all of the head bolts and spun the head round on the bolt to remove it. On inspection, all looks well. Excuse the poor picture quality, I'm using my phone:



Are these chambers standard?



How should I go about cleaning the tops of the pistons, and chambers. I have done it before, but unsure how to approach it this time round - what works best?

Tom

[Mini_Lund]

guru_1071 said:

1275 a plus motors do have a habit of sticking on that centre bolt - i think at some time the hole centres moved a little in the heads. that one is always the worse cuplret.

ive had to resort to various methods before to get them off!

...and those various methods are?

I'm leaving the MG engine alone for a while now, Im going to hack the gearbox off the 1275 and diff off the 998...wish me luck, there's no doubt in my mind that its going to be a struggle!

[Mini_Lund]

guru_1071 said:

Mini_Lund said:

...and those various methods are?

1) heating the head up with oxy bottles and spraying WD40 around the stud - worked ok. - but took ages, about a week of warming it up and leaving it overnight - i didnt want to damage the head by getting it too hot.

2) welding a nut onto the stud and winding it out with a socket - worked the best (this works with thermostat studs as well!)

3) hanging the engine from a decent chain (attached to the head) and jumping up and down on the gearbox. did work, but not recomended!!!!

4) getting the head up about 5mm and sawing the studs through with a hacksaw blade wrapped in tape.......not a exercise i will ever repeat, no matter how stuck the owner of the car is. this was before i owned decent tools, a trailer etc etc!!!!!

interestingly heads sticking to blocks was such a common problem for 1950's bentleys, they actually had a special tool that could be attached which would 'jack' the head off the block in situ!

fortunatley the heads ok on ours (at the expense of body work, but hey ho!)

i have ad an engine in the past that had obviously had this problem, when i removed the head and cleaned it the centre front studhole casting 'lump' was flattened and the casting had a hair line crack about 1" from the top surface downwards, caused by some fool braying at the head with a large hammer.

Edited by guru_1071 on Sunday 18th January 19:44

All of the above I have tried! But I'll keep at it, persistance shall pay off! Why do I not clean the tops of the pistons? I'd like to know what they are, if theyre anything special or not. Guru, would you say, judjing by the pics, has my head been ported?

[Mini_Lund]

I have put the MG 1275 to one side for the moment. Today I took the diff off the 998, and then decided I'll use the box on the 998 as its the same casting as the 1275 box, and the gears engage nicely using the selector. Of course I cannot tell which is the better box without takin the box off, but I'll gamble and try my luck with the 998 box as it has all been sealed with plenty of oil in. The 1275 is missing the diff.

Both castings are D5626. The diff looks clean and in good condition - I have never had a diff off or a box off the block, so I didn't havt a clue what to expect...



I have loosely put the diff back on the 998 box, (just 4 bolts for now). I have managed to loosen most of the bolts fixing the box to the block, however am I right in thinking I need to get the flywheel and housing cover off to do this? I've have undone most of the bolts, but can't get to some as they are behind the fly.

I removed the large bolt in the centre of the fly and the several bolts around the outer edge, but it will not shift - do I require a flywheel puller?

Thanks in advance, Tom

[Mini_Lund]

MHM said:

Lost track of you gearbox/diff combo but if you are swapping diffs keep diff housing with its original box.
When you pull flywheel make sure you remove the washer and wind the big bolt back in leaving a few mm gap. If that flywheel hangs on there they cant half go across the floor or worse if its on a bench and falls on your foot.

Sorry, I have even managed to confuse myself. Bare with me! I will be using both the 998 box and 998 diff as the gearbox is the same as that on the 1275. I've heard about central oil pickup pipes, is that a welcomed modification to my gearbox?

guru_1071 said:

yep

you need a puller to get the flywheel off

then the transfer case can be removed.

then the engine can be lifted of the box.

Thanks for the heads up, I'll put the bolt back in so the fly doesnt scream across the room! Apparently they don't half make a 'crack' when they are removed.

When I removed the diff a small spring popped out, I can see a small ball bearing on the gearbox case itself, (bottom right) with diff removed, im guessing it has popped out from there when I removed it.


ETA: On another note, I managed to knock all the conrods out of order! So where do I stand with the conrods; Do I buy new ones or put these back in and wear the engine in. They all seem in good condition. & & I never noticed how the MG 1275 is a shorter block than a mini 1275. No head bypass hose or tappet chests.

Edited by Mini_Lund on Monday 19th January 18:36

[Mini_Lund]

Skyedriver said:

Have the rods not got little centre punch marks on them indicating 1, 2, 3, 4,? Near the big end and the cap may be similarly marked

I haven't noticed, but I'll have a look, thanks

[Mini_Lund]

guru_1071 said:

all the 1275 blocks are the same height - there may be a few mm differance (to account for the piston heights), but if its more than that you either have serious problems, or something very expensive....

Yeah, I just noticed. I was comparing the 1275 to the 998 and was sitting in the garage like 'hold on a minute!'

minimadmotorman said:

When you say conrods do you actually mean pushrods?

I think so yes, the rods that push the tappets.

Im just embarrasing myself now, you'll all be thinking its a bloody miracle if i get this engine working...

[Mini_Lund]

minimadmotorman said:

Don't worry about mixing the pushrods up.

Okay thanks, Just my old fella had a go at me and I couldn't understand why...

ETA: I need to find my puller before I can make any real progress

&& my 850's running rough, I suspect the carb, it wont idle for long just the ignition light comes on and then it cuts out. Its an absolute nightmare to drive. No revs behind the accelerator pedal > too lean?

Edited by Mini_Lund on Tuesday 20th January 12:57