engine

[stuupnorth]

thanks for all the input with regards to my questions
so if I manage to get a standard 1275 flywheel and a standard 1275 clutch assy
it should be ok with a 1098 box? which clutch fork the 1098 one? and release bearing??
I have a ' Declan' rose jointed clutch linkage set up ready to install when the engine /box goes in
so that should help with 'heavy' feel to the clutch?

[ampwhu]

I took it from phil's advice above that to keep the mechanical clutch arrangement, you would need the following
1275 flywheel
1275 clutch (pressure and friction plates)
1275 clutch thrust bearing
1098 clutch fork.

[philthehill]

For 1275cc Midget/Sprite engine - Correct.

[stuupnorth]

again many thanks guys

[ampwhu]

main bearing crankshaft.JPG (31.34 KiB) Viewed 1245 times

this is one of the crankshaft main bearings. the numbers stamped on it, is it the part number or does that 020 indicate it has been reground to 0.020"

[philthehill]

AEG 158 is the part number.

020 indicates that the bearing fits a main bearing that has been reduced in diameter by 0.020" by regrinding.

[ampwhu]

cheers as always phil. so I think it's best I exchange the crank for another as there are some marks on the surfaces.

ESM must do an exchange 1275 crank for the midget.

[philthehill]

ESM only list the 1275cc Marina/Ital crankshaft.

MOSS Europe have the 1275cc crankshaft on back order.

There are several 1275cc MG Midget/Sprite crankshafts on 'e' bay which may be your quickest route to getting the engine back running.

This one looks to be suitable and much cheaper overall than the usual suppliers:-

https://www.ebay.co.uk/itm/MG-MIDGET-12 ... SwrhFeKx1L

The seller in the link above has several 1275cc crankshafts available at varying prices.

[oliver90owner]

...some marks on the surfaces....

Exchanging/regrinding the crank, for me, would depend on what you mean exactly, and the dimensions of the crank - ovality, size. The marks may be cleaned up with fine abrasive, or maybe not.

I suppose it is better to exchange if you are not sure.

[ampwhu]

...some marks on the surfaces....

Exchanging/regrinding the crank, for me, would depend on what you mean exactly, and the dimensions of the crank - ovality, size. The marks may be cleaned up with fine abrasive, or maybe not.

I suppose it is better to exchange if you are not sure.

i'll get some pictures

[ampwhu]

crank1.JPG (131.53 KiB) Viewed 1226 times

crank2.JPG (104.96 KiB) Viewed 1226 times

if i attempted to polish out the marks, how would I go about it? I have nothing to loose. the marks aren't deep.

[paul 300358]

The best and cheapest option is to get the mains reground to -30.

[philthehill]

Having looked closely at the photos the best option would be to regrind but that may not be possible under the current circumstances as your local engineering firm may have closed its customer counter or have closed for the duration.

If you run your finger nail across the journal does the radial (around the journal) grooving stop you doing so?

If there is little resistance to running your finger nail across the journal you can always use some very fine (7000 grade) wet and dry paper
on the journal. Soak the wet and dry in WD40 or similar before running the paper around the journal. Do not let the wet and dry paper dry out and do not concentrate your efforts in one place but spread your efforts all around the journal.
7000 grade wet and dry is available on 'e' bay.

Make sure that you clean every morsel of wet and dry paste off the journal before reassembly.

[ampwhu]

if I run my finger mail over the area there is virtually no resistance/markings. I think the pictures make it look worse than it is.

ok Phil, I think I can manage this.

[philthehill]

ampwhu
Thanks for the reply
If the case is no resistance to the finger nail then it is possible to make the journal usable again without resorting to a regrind.

Phil

[oliver90owner]

There is always a tolerance on regrinds. If yours cleans up (possibly only ‘polishing’) within those tolerances it should be as good as a freshly reground crank.

Accurate measurements are the secret, as well as the physical attention given to the bearing surface, as the final clearances between crank and bearings needs to be within the design spec.

You can buy a lot of abrasives for £150. But first make those measurements.

[stuupnorth]

hi
manged to get a 1275 flywheel and clutch (owner of engine had one!)
any idea of the bolt threads for the flywheel
had a look on 'Moss Europe' and they list this
https://www.moss-europe.co.uk/bolt-flyw ... k1029.html
or this one
https://www.moss-europe.co.uk/bolt-flywheel-6k630.html
cheers
Stu

[IslipMinor]

From the 'Thread Sizes' post at the beginning of this 'Mechanical' section they are 3/8" UNF.

[philthehill]

The high tensile bolts are special to use and normal bolts should not be used.
Every effort should be made to obtain the correct items or suitable alternatives.
These bolts
https://www.ebay.co.uk/itm/ARP-competit ... 0752.m1982
are competitively priced and if standard items are unobtainable from the normal suppliers they are a very good substitute.
With the ARP bolts the lock washer https://www.moss-europe.co.uk/lock-tab- ... soc=143940 is not required but I would advise that the bolts are Loctited in place at the manual specified torque.

[IslipMinor]

From the same 'Thread Sizes' source the torque setting is 40 lbf. ft.

I use HT socket head cap screws, with Loctite on the threads and tightened to the recommended torque setting.