1275 engine identification

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Sleeper
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1275 engine identification

Post by Sleeper »

Dear All

Just picked up a A+1275 engine with no identification plate fixed , I'm not really worried that I'm receiving stolen goods as I believe when the blocks are skimmed they tend to get lost , Identification marks as follows.

Numbers .. Head 12G940 157.

Block .. X 16L WFM 2 12 BL ( feint ) , A and cast in , the Austin-Rover logo ?

Anyone?

Photos if needed...

Thanks
John
philthehill
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Re: 1275 engine identification

Post by philthehill »

1275cc Marina 'A' Plus.

Sleeper
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Re: 1275 engine identification

Post by Sleeper »

Phil
Many thanks, just waiting for my copy " Tuning BL's A-Series Engine by Dave Vizard "

John ;-)
philthehill
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Re: 1275 engine identification

Post by philthehill »

Just seen your photos of the 1275cc 'A' Plus engine on the Morris Minor Owners site.
Marina engine 3.jpg
Marina engine 3.jpg (294.93 KiB) Viewed 1771 times
The block has WFM1120 cast into the top o/s of the block. The Marina/Ital 1275cc block does not have those numbers. Therefore I have to reassess my opinion as to what vehicle the block came from. I now of the opinion that the block came from a 1275cc Maestro. It also has the Maestro engine mount bolt holes at the front o/s of the block.
You seem to have bought a hybrid engine as the crankshaft rear end looks to be 1275cc Midget as there appears to be a register on the end of the crankshaft.
If it has the 1275cc Midget crankshaft fitted you are in luck as the 1275cc Midget crankshaft is a much better item and is more useful when tuning the engine. Also if the crankshaft is 1275cc Midget that means the Midget conrods have to be used as the size of the big end journals are different. The 1275cc Midget conrods are again better than the Marina and gives you the opportunity to use 1275cc Cooper S conrods in EN24 steel (the best factory/production rods available).
Replacing the Marina crankshaft with a 1275cc Midget crankshaft is a well trod route to get more reliability and improve its tuning capability.
My own 1380cc engine is based on a Marina 'A' Plus block with a 1275cc Midget crankshaft fitted.
Below is a Marina crankshaft, note the parallel outer face of the flywheel mount flange.
The 1275cc Midget crankshaft flywheel mount flange is not parallel. It has a angled face which is the register.
Marina crankshaft 1.jpg
Marina crankshaft 1.jpg (60.42 KiB) Viewed 1784 times
Below is the rear of the 1275cc Midget crankshaft. Note the angled register. Ignore the central roller bearing and carrier. That was installed to carry the first motion shaft of the Quaife SC/CR gearbox.
Midget rankshaft tail.jpg
Midget rankshaft tail.jpg (44.56 KiB) Viewed 1783 times
The head is secured by 11 fixings and which could have come from a 1275cc Cooper S, 1275GT or 1275cc Wolseley/Riley.
So again a real hybrid and has all the positive things that you require for tuning a 1275cc engine.

The engine also appears to have been converted from the Maestro crankshaft lip seal to the oil thrower/scroll set up for the rear main.

All I can say is that are a lucky chappy.

Phil

Sleeper
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Re: 1275 engine identification

Post by Sleeper »

Phil,

Thank you , I don't want to, but looks like I may have to split it to be sure... or at least drop the sump..

The more I look at it the more I am thinking that it could be too much work.

John ;-)
philthehill
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Re: 1275 engine identification

Post by philthehill »

What is behind your thinking of too much work?
You do not have to drop the sump to identify what crankshaft and con rods are fitted - just look at the rear of the crankshaft. If as described and shown above and has a register the crank is 1275cc Midget and therefore the conrods must be 1275cc Midget. You cannot use Marina/Ital or Maestro rods with a Midget crankshaft.
The Marina/Ital and Maestro big ends are 1.75" dia. The MG Midget big ends are 1.625" dia. All main bearings are 2" dia.

Phil

Sleeper
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Re: 1275 engine identification

Post by Sleeper »

Thanks again, yes it has the " taper" on the flywheel , will have to think about things , due to lockdown and the bitter winter I don't think I could justify another moggie build ,

Are there any variations of valve sizes?
Maybe I should have a look at the cam timing/lift ?

On the other side someone asked for a photo of the front cover ? posted...

Thanks
John
philthehill
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Re: 1275 engine identification

Post by philthehill »

There are variations in valve sizes fitted to the 940 head. If standard sized valves are fitted to the head in question they are a good size and will not require changing.
The full spec of the engine will not become apparent until the engine has been stripped.
Here is a Maestro engine for sale on 'e' bay. Note the engine mount at the o/s front of the block. The engine is suspended not mounted as per the Minor.
https://www.ebay.co.uk/itm/a-series-127 ... SwlThdrvpY

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