Engine identification.

[BOC]

Please could anyone help me to identify the origins of this engine?
Unfortunately the engine number is missing. It has a 1000 tag on it, a 12G295 head with double valve springs. On the block Mowog 3, 804 and 12a 497.
On the box, Mowog sm 22g68 6120 R
Thanks in advance.

[ricardo]

Probably an early 998 Cooper engine.

[Toby]

It's thin flange so it would mean fairly early. However it already has an oil catcher on the tappet chest cover, they got introduced in 64. Would there be any markings on the rib on the top of the flywheel housing?

[mk1]

Looks like a 998 Cooper to me too. It has a fairly early flywheel housing too.

Are you sure that this engine is intact or has it been assembled from bits some time in its distant past?

[BOC]

I’ve cleaned the paint off the rib and again no numbers. It was passed to me as a 997 cooper, but I’m just trying to confirm this. I didn’t really want to start pulling it apart as it was rebuilt.
I’ve no way of knowing if it built up from various engines.
Thanks for the input.

[mk1]

I would suggest that judging by the amount of rust on & around the rocker gear that it will almost certainly need a rebuild before it will run again therefore whipping the head off will not be to great detrement to the rest of the unit, you will instantly know whether its a 997 or 998 once you can see the bores.

The early clutch housing point to it being early (997), but the cannister on the back & 295 head imply its later (998).

[ace01]

Only by taking off the cylinder head will you find out for sure. A 997 overbored 20thou will accept a 295 head. The 1000 badge on the back of the block was fitted to later 997s and early 998s. Like wise there may be a number stamped into the block above the waterpump. This was common to 997s, early 998s and some of the S lumps.

[BOC]

Thanks for the replies. I’ve pulled the head off .The pistons have M2039W46 stamped on them.
Using a ruler the bore is close to 65mm and stroke 80mm. The valves are very shiny almost like stainless, is that possible?

[InimiaD]

Sounds more likely to be a 997 cooper.
The standard bore for a 997 is 62.43 mm and the stroke is 81.28 mm.
Hope this helps.

[ricardo]

12A497 are 998 blocks (STD = 64.58mm x 76.20mm) or 1098 blocks (STD = 64.58mm x 83.72mm).
You have to have an accurate measure of the stroke or check the part number of the crank.
A 998/1098 block at +0.20 has a bore of 65.09 if it helps.

The valves and pistons are that clean because the engine wasn't run after the rebuild...

[12g295]

998 coopers had "D top" flat pistons. So if it is a 998 cooper then they have been replaced in the rebuild. This engine has dished pistons, the 12G295 head has a large chamber volume so it would have been skimmed a lot to restore the compression ratio.

[mk1]

Those valves look VERY recessed into the head!

All engine valves are stainless.

[BOC]

Thanks for the replys.It looks like its a mix of parts.
The question now is , should I use it or hang out for a 1275.
What might it be worth ?

[mk1]

Looking at this engine, it may well have been rebuilt & not run since, but it is certainly NOT in a condition that I would attempt to run it in. It really needs a full strip & rebuild to make sure its right.

With this in view I would strongly suggest that you hold out for a better option either another small bore or a 1300. Always better to buy s/h engines when you can see them running or in bits buying a lump like this one is a totally unknown quantity.

[BOC]

Ive got the block off the box and found the numbers 2A596 and JGSB14 on the crank.Does this mean anything to anyone ?

[ricardo]

12A595 - 998cc - Early EN16T spec