13 replies to this topic

[whooshee1380]

Can you people help me as ive brought some main bearing for my a series and all 6 of them are the same and my old one have 3 different one.Its were the cut out is 3 are in one corner an the other 3 are in the middle on the engine.HAVE i ordered the wrong one as i only noticed when i was about to fit them.I ordered big end bearing for a series and they were fine.Can YOU HELP PLEASE AS MY NEPHEW WAS CUTTED WE COULDNT REBUILD THE ENGINE TODAY. MANY THANKS

Edited by whooshee1380, 15 September 2012 - 07:43 PM.

[MiniElliott]

I think the bearing locating tabs only changed position with the A+ engine. A series engines have the locating tab at the corner. So it could be that you have a mix of A series engine and A+ Main caps.

Do you know if the engine has been rebuilt/ dismantled in the past ?

Elliott

[whooshee1380]

Hi there it looks like it has bin as there is plenty of gasket sealant on it,lol.I did notice that one of the old bearing didnt match up to the holes in the main block i think it was the clutch end were the oil ways didnt match up.What would be the best to do start again with all the same parts or get some A + series bearing .Thanks for your help

[MiniElliott]

The bearing oil hole is correct. That's how they came from the factory. And if it was me I would get hold of some matching main caps. However you may need to get the block and caps line honed to make sure they are perfectly matched. It may be cheaper to buy a A+ set of bearings and mix and match again. The only problem is that since the bearing caps have already been swapped you might already have the same problem as swapping caps again.

Hopefully somebody else will give a second opinion.

[whooshee1380]

HELP PLEASE CAN ANYONE ELSE SHED LIGHT ON MY PROBLEM PLEASE .

[Artful Dodger]

Get pics up of every bit you are having issues with:)

[firefox]

The engines pre 1983 bearings and main caps had all the cut outs on the bearings on the outer edges

engines and main caps 1983 on have 50% edge and 50% centre this apparently was to stop people putting

the bearings in the wrong way around and covering up the oil ways, i had the same problem with the big

end bearings, not sure if it applies to the mains , ring mini sport they are aware of the problem

[MiniElliott]

Firefox when did this end. I have 2 pre 83 engines and 1 A+ 85 engine and none of the bearings are mixed as suggested. Saying that, it was built by BMC/ Leyland so there may never be a difinitive answer.

Elliott

[Cooperman]

If you have bearing shells with the wrong tang position it's possible to file the cap with a small draw file to make a new tang position. I've done it a few times when the correct shells were not in stock. Just make sure everthing lines up correctly.
The A+ caps had different tang positions in the main caps from the pre A+.
I't not a big problem. Alternatively just buy shells witht he tang positions correct. With the A+ the shells in the caps have the different offset, not the ones in the block.

[whooshee1380]

Well thanks everyone i got a bit losted with it all so i rang mini sports ad there sending me some other bearing,i did ask if i could mixs an match the bearing and he said not to.So will see at the weekend if there the right ones.I will but somepictures on when i get some at weekend from the garage.I have 2 words to say F...ing cars lol lol

[firefox]

Firefox when did this end. I have 2 pre 83 engines and 1 A+ 85 engine and none of the bearings are mixed as suggested. Saying that, it was built by BMC/ Leyland so there may never be a difinitive answer.

Elliott

I found out on the internet somewhere that BMC when they were low on stock used differnt parts available, well to hand untill stocks were replenished
so main caps and and big ends could be mixed up this was to carry on production, but the rule of thumb is pre 83 as i have explained

[Cooperman]

Just remember that you can't take a set of caps, big end or main, and use them on a different block, or on different rods.Each main cap is specific to the block and each big-end cap is specific to that rod and can also only be fitted one way round.
With the A+ blocks the main caps had centre-position tangs in the caps and offset tangs in the block. No idea why it was changed, but that was Austin-Rover, nothing had much in the way of logic applied in respect of design changes.

[firefox]

Just remember that you can't take a set of caps, big end or main, and use them on a different block, or on different rods.Each main cap is specific to the block and each big-end cap is specific to that rod and can also only be fitted one way round.
With the A+ blocks the main caps had centre-position tangs in the caps and offset tangs in the block. No idea why it was changed, but that was Austin-Rover, nothing had much in the way of logic applied in respect of design changes.

As i said peter something to do with pre 1983 not all A+ blocks have the same tangs this is what i was told off minisport no pre 83 engines had centre tangs
well that is what i was told , they were changed in 83 to stop people blocking the oilways, please correct me if it is wrong

[Cooperman]

Just remember that you can't take a set of caps, big end or main, and use them on a different block, or on different rods.Each main cap is specific to the block and each big-end cap is specific to that rod and can also only be fitted one way round.
With the A+ blocks the main caps had centre-position tangs in the caps and offset tangs in the block. No idea why it was changed, but that was Austin-Rover, nothing had much in the way of logic applied in respect of design changes.

As i said peter something to do with pre 1983 not all A+ blocks have the same tangs this is what i was told off minisport no pre 83 engines had centre tangs
well that is what i was told , they were changed in 83 to stop people blocking the oilways, please correct me if it is wrong

It is hard to believe that they produced the A-series from about 1955 until 1983 and then decided that the main bearing cap tangs needed to be moved. Who knows what went through the design department's mind when it was Austin-Rover. For example, they mixed Imperial and Metric threads on the braking system and how crazy is that. The oilways never blocked in the earlier engines. Anyway, the oil holes are in the block where the shells have the tang in the same position.
I had some A-series shells in my stock of bits and was building an A+. I was told that A+ mains were out of stock, so I filed a second slot in each cap so that the shell sat right mid way in the cap. It was really no problem and ran fine.