5 replies to this topic

[MiniLuke]

Right all you clever knowledgeable Mini people, can anyone identify what this engine number means, 28G-274-998

The block has a casting number or 12A 497 with 247 cast into the front.

The number 28G-274-998 is attached to a block I have bought, which is supposed to be a new block. however I think it has been linered, see second picture.

Could anyone let me know if a linered block is any good? Is it reliable?

Should I complain as the block has the impression of being new in every other way. Can anyone see any major problems using a block with liners in the cylinders? were they ever used from new?

Any advise would be welcome

[Dan]

It's a factory replacement / Unipart type of engine number but not one specific to a Mini I believe.

Complain? You should take this so quickly you risk pulling the guy's arm off! There is absolutely nothing wrong with a linered block, in fact they are better than a plain block in many ways. The liners will last forever more or less. This engine will see very little wear if you build it right and run it in properly. The steel liners are far harder than the cast iron block. Liners were never part of the spec but were sometimes fitted to brand new engines and replacement engines and blocks. If an engine was damaged on the machining line then liners would be pressed in to save it, especially if there was a strike going on in the foundry that day. Often these made their way into the replacement engines but sometimes the blocks were used for original equipment engines. The only drawback you may have is that it isn't a seasoned block so might not be so good for making a high spec engine (many builders prefer using an old block that's been heated up a few times over a brand new block). Having said that, it doesn't really matter. Because of the liners you pretty much can't use it for a large overbore now but as a standard build it will be perfect. You can go to +30 in a liner I think, or press in new liners if it gets damaged.

[Guess-Works.com]

I suspect 28G274 is the part number, eg 28G252 is the p/n for a bare 850 block, this is the reason the tag is not riveted to the block, it hasn't got an "engine" number yet as it's not been built.

Should be an A series small bore ( intended to be used as a 998 )

The liners could well be a factory fit, it's not uncommon for engine after casting having issues so would have had liners fitted ( possibly the reason why it is on the parts shelf rather than having been built into a production engine )

[MiniLuke]

Hi, thanks for the replies.

I had a suspicion it may be good to use, glad I checked on here before moaning/complaining etc.

Hopefully it will be the basis of a very nice standard 998 engine to replace the smokey unit in my 1972 mini.

Is it ok to put the engine number from the original 998 onto the new built engine then? I guess so if the block has never been used as it is just replacing

Thanks again, TMF really is a fountain of knowledge.......

[Jools33]

Thanks for that, so I take it's a 998.

[62S]

Right all you clever knowledgeable Mini people, can anyone identify what this engine number means, 28G-274-998

The block has a casting number or 12A 497 with 247 cast into the front.

The number 28G-274-998 is attached to a block I have bought, which is supposed to be a new block. however I think it has been linered, see second picture.

Could anyone let me know if a linered block is any good? Is it reliable?

Should I complain as the block has the impression of being new in every other way. Can anyone see any major problems using a block with liners in the cylinders? were they ever used from new?

Any advise would be welcome

As Guessworks says the number is a part number not an engine number or at least 28G 274 is the part number. The 12A497 became a commonised casting so the 998 was added to the tag to aid identification.

This is a 998cc block, specifically for a car with a mechanical fuel pump so it should have the relevant machining to suit.

Yes, liners were used from new by BMC. Many A series blocks came linered from the factory.

Edited by 62S, 20 September 2015 - 08:39 AM.