Morris Minor Owners Club

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New engine definitely, large ends and mains 0.003" oval. pistons US. Keep it as a spare engine and do it up when you have some spare money. smithskids. There is an 803cc engine in the next village to me and a ribbed gear box for sale £50.

I think the price quoted will be for an 'exchange' engine... That deal next village is effectively a 'free' 803 -which miserable as it is - would be a handy emergency spare !

Googled and emailed around, but cannot get a complete engine for a reasonable price.
Now I go for the second best (but far more challenging) solution: new block, new crankshaft, new (unleaded) head, and rebuild myself. One big advantage: i'm sure what i'm getting without taking the new engine apart. And i will have some fun this winter.

Two questions:

The guy who did the measuring mentioned something about aligning the con rod (right word?). How can I know this is really necessary? From the pattern as seen on the pistons, I can't believe the damage of the pistons is caused by this (damage should be on top of one side and at the bottom of the anther side).

Someone told me the damage of the pistons could be caused by bad cooling: the pistons tend to get oval shape when heated up, with the longer size in the direction of the piston pin. All pistons showed similar pattern: damaged in this direction. See pictures below. Possible?

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I think your conrods will be straight enough... To check you would need a tight fitting (and dead straight) bar through the eye - and another through the big-end - and measure either side. It's highly unlikely they will be bent - compare them to each other! It's most unlikely ALL will be bent.... If I was buying a head - I would be looking for an upgraded head - not just 'unleaded' - probably won't cost any more. I would also fit the Mini timing chain with tensioner for quiet running. If the camshaft needs replacing - then that too could usefully be upgraded. (MG Metro or Kent 246) and of course a crankshaft damper would be handy.

Collected my new parts (block, head and crankshaft) last week, unpacked it today

The block is a + 0.02" and the pistons are delivered with it. Measured the piston in the cylinder bore at top, and a feeler 0,3 mm could be inserted. I assume that is OK.

Put the top piston ring on the lowest expected position in the cylinder bore and measured the gap: 0,5 mm (0,02"). According the the workshop manual it should be less than 0,28 mm (0,011").

Below the label of the package. It says: G1349 020. Does the code say it is suitable for a +0,02 bore?

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Yes - that will be 20 thou overbore. Are the pistons themselves not marked 020 on the top?

Is the gap of 0,5 mm in the top ring not a problem? I did not check the other ones. Are these the same size?

Yes, pistons are marked 020

Don't worry about it..... Just concentrate on NOT breaking the rings -and getting them on right way up!

According to the wksp man the fitted gap for a 1098cc piston ring is 0.178mm - 0.305mm.
I would suggest that your piston rings are ok for ring gap as the 0.195mm can be lost in translation i.e. the feel of the feeler gauge drawn through the gap.
Did you press the piston ring down the bore with a upside down ring-less piston so as to keep the ring square to the bore? If you did not that can add to the gap.
As bmc says make sure that you get the rings the right way up. They are usually marked 'T' ('TOP'). Also make sure that the gaps are at least 45 degrees away from the one above and the one below and are well oiled when piston and ring are inserted into the bore.
The pistons are usually marked 'F' ('FRONT') as well.

Did you press the piston ring down the bore with a upside down ring-less piston so as to keep the ring square to the bore? If you did not that can add to the gap.
As bmc says make sure that you get the rings the right way up. They are usually marked 'T' ('TOP').

Yes, measured after pushing it down with the piston. Yes, the rings are marked 'top'.

Any advise for the best way to put the rings on the piston?

Thanks,

Purchase a piston ring fitment tool and you will not have any problems.

http://www.frost.co.uk/piston-ring-installer.html

http://www.frost.co.uk/pro-piston-ring-tool.html

You can wind the rings on but better to spend a little and do the job properly and without the fear of breaking a ring.

I use a similar tool and never had any problems.

I use my fingers - quite painful - but no problems with the rings to date.. I guess the tool will be a good investment for you.

Suggest that you check all the rings for end gap before installing them.

This is the tool I use for adjusting the gaps on piston rings:-

http://www.cylinderheadsupply.com/4288.html

If the ring gaps are tight it is difficult to adjust without the proper tool.

Phil, That's exactly the same one that I have but I only paid 45USD on US Fleabay at the time.
http://www.ebay.com/itm/Piston-Ring-Fil ... 6f&vxp=mtr
Never used it as when I replaced the rings and pistons on the MG the gap was spot on. I know that if I sell it I will need it in the future.
Regards
Declan

Theo... you measured one and it was fine - I bet the others are all the same... Keep your money in your pocket...

Declan
I bought my ring gapping tool years ago from 'Eastwood Restorations' and if I remember I paid about £20 for it.
When I fitted the rings into the Minor 1380cc bore I did find that I had to take a little off the rings to get the specified gap correct and the grinder came into its own.
Whilst I agree with bmc in that the rings are most likely to be correctly gapped it is always better to check them all before fitting and personally I would feel much happier having done so.

Phil,
Couldn't agree more-that's the reason why I bought that tool in advance and watched the U-Tube videos on how to use it. I did check every new ring and they were all spot on right out of the box so never needed the tool. The old ring were way off!
Regards
Declan

If even one ring is slightly long it can cause trouble, that's why I always check all rings for gap. Over the years I've found lots of rings that were too long. I don't use a special tool as Phil posted, just put the ring in a vice and file a wee bit off the end.
YMMV