Need help IDing A-series engines

[Darel]

I bought my '61 Bugeye last fall in pieces. It came with 2 engines, both out of the car. One had been rebuilt a few years ago, never installed, 0 miles. The other engine is simply used - covered in grease. I had always assumed these were 948 motors.

I got a bug (no pun intended) in me today to clean off the tags and had a nice surprise. The filthy old motor is a 12CJ7DA/H, a 1275 out of a later Sprite. Nice!

Unfortunately, the rebuilt motor is missing its' ID tag. How can I tell what engine this is? A lot of bits are not correct to a BE, so I really can't even guess. It came with a generator, but the gen has no provision for a tach drive. The fan is steel four-blade and it has a canister oil filter. The 1275 has a plastic fan and spin-on oil filter.

How do I go about figuring out what motor this is? Geez, I wish it was the 1275 they rebuilt. I'm afraid now due to the fan, generator and oil filter this may actually be an older engine than a 948, perhaps even an 803 or something. I'm too new to BMCs to know by sight - what do I look for?

Thanks,
Darel

 

[Sarastro]

The 948 and 1098 have removable covers on the left (driver) side of the engine; the 1275 doesn't.

Not sure if there is any simple way to distinguish between the 948 and 1098 just from external characteristics, but I'm sure someone will tell you if there is.

 

[Darel]

I've got a removable cover.

 

[spritenut]

On the front carb side, a tag will read 1100 if it is a 1098.
On the carb side near the rear of the block it will be embossed with 950 if it is a 948.

 

[Darel]

I've got a 950.

So now it's decision time - run the rebuilt 948 and sell the 1275 to finance bodywork, or sell the rebuilt 948 to finance building the 1275.

It doesn't have to look pretty, right?

 

[jlaird]

Run the rebuilt 948 and stash the 1275 for another year or so. Meanwhile enjoy your ride.

 

[drooartz]

I'm with Jack on this one. Run the 948 you have for now, and save up to build the 1275 some day. Driving is good!

 

[JPSmit]

FWIW you won't likely get enough out of either engine to make selling it worthwhile.

 

[Sarastro]

I agree with Jack, and also John-Peter. I've seen a couple 948s on ebay, even one complete with carbs, distributor, the works. The latter sold for less than the external parts would cost. Others haven't sold at all. Used 1275s go for only a few hundred bucks, if you're lucky.

Once you have the 948 in and going, you'll have a better idea whether you want to invest the time and money to rebuild the 1275. I had a 1275 here, which I rebuilt, but when it was done, I decided not to use it. The 948 was running so well that I hated to start over, just for a little more power. In the end I sold the 1275 for about what I put into it.