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What year and model number is this 1275?
- Thread starter smaceng
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Distributor and carb numbers might give you a clue, but of course these could have been replaced. Then, check...
https://www.spridget-tech.com/page3.html
https://www.teglerizer.com/mgstuff/advance_curves.htm
The Brooklands book, "SU Carbs Tuning Tips and Techniques" has a table of carb numbers.
Seems clearly an early engine, whatever it is. Note also the connection for a mechanical tach.
https://www.spridget-tech.com/page3.html
https://www.teglerizer.com/mgstuff/advance_curves.htm
The Brooklands book, "SU Carbs Tuning Tips and Techniques" has a table of carb numbers.
Seems clearly an early engine, whatever it is. Note also the connection for a mechanical tach.
dklawson
Yoda
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The head is a 1275 for sure as the heater valve take-off is at 45 degrees to the rockershaft centerline. The dizzy looks to be a 25 series. Steve, where's the tach connection you mentioned? Are you talking about the head on the back of the generator?
The following is as much a question as an observation. Did the 1275 inline A-series (from the 1960s) NOT have removable tappet chest covers? The picture above looks like the "back" of the block has no removable covers. I also don't see a place on the back of the block for the mechanical fuel pump.
The following is as much a question as an observation. Did the 1275 inline A-series (from the 1960s) NOT have removable tappet chest covers? The picture above looks like the "back" of the block has no removable covers. I also don't see a place on the back of the block for the mechanical fuel pump.
aeronca65t
Great Pumpkin
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No tappet covers or mech fuel pump area on 1275.
I was wondering about the breather "can" on the timing chair cover?
I'm not home right now so can't go and look at my engines (two 1275s, a 948 and a dissassembled 1098) to see which ones had this....I dont'think they all did (I can't recall).
The tach drive is at the back of the generator....that's an early generator for sure.
I was wondering about the breather "can" on the timing chair cover?
I'm not home right now so can't go and look at my engines (two 1275s, a 948 and a dissassembled 1098) to see which ones had this....I dont'think they all did (I can't recall).
The tach drive is at the back of the generator....that's an early generator for sure.
OP
smaceng
Jedi Knight
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Here are some additional pictures. The generator has the tach drive, so it was from a 948. The block does not have tappet covers and it has a tag which says "1275" Terry Horler's book said that the 1275 did NOT have the vent tube on the top of the rockers. The rocker cover may be from an earlier model. The block is embossed with a "12G 949" in the left-rear corner, has a number "03G" embossed at the left front and the number "088" or "880" depending if you are right side up or not. Just to help out, the carbs do not have tags, but are 1 1/4".
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jlaird
Great Pumpkin
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Obviously the generator is early mechanical tac drive, the valve cover is also early so the breather can go to the front carb air cleaner. Looks like an early fan set up as well.
The breather on the timeing chain cover is correct for a 1275 and of course the cast block for the manual fuel pump and the lack of tappet chest covers make it a 1098 or a 1275.
I am going to guess at a 1098.
Hay where are the experts on engines today?
The breather on the timeing chain cover is correct for a 1275 and of course the cast block for the manual fuel pump and the lack of tappet chest covers make it a 1098 or a 1275.
I am going to guess at a 1098.
Hay where are the experts on engines today?
Dug
Jedi Trainee
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1275 block and head, looks like a thick flange 1275, kinda of hard to see with the "blue goop" spread between it and the pan to say.
If so it's an early 1275.
With the engine tag gone it’s a fair bet it's been reworked and over bored once but strange it still carries the alumn tag listing 1275(hot tanks eat both). Given that none of the 1098's cc or cg were without tappet areas and their covers, we know it’s a 1275 with some 948 bits thrown in for good measure.
"dug"
And yes it's true 1275's didn't have tappet covers when configured as inline engines from the factory but not true when transverse fitted, i.e. Cooper S
If so it's an early 1275.
With the engine tag gone it’s a fair bet it's been reworked and over bored once but strange it still carries the alumn tag listing 1275(hot tanks eat both). Given that none of the 1098's cc or cg were without tappet areas and their covers, we know it’s a 1275 with some 948 bits thrown in for good measure.
"dug"
And yes it's true 1275's didn't have tappet covers when configured as inline engines from the factory but not true when transverse fitted, i.e. Cooper S
Hap Waldrop
Yoda
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It a 1275 for sure, and that a smog area head, which makes it a 12G1316, so the mystery is pretty much over, as mentioned earlier, no A-series except the 1275 was ever produced void lifter cover on the block. From there basicly all inline 1275 engines are the same, in the early 1275s the was a block is solid under the center main webbing in the block, and these block most often had the coveted EN40B crank, but the other block only have a small pie shaped opening in the center main webbing, and had the EN16T crank, the same crank, just tuffrited intead of nitrited and made of EN16 sreel rather than EN40 steel.
Side note: Some 1275 engines do in fact have mechanical fuel pump blanking plate, Ray's engine, that I'm building right now is a late 72-73 block and it has mech. fuel pump blanking plate, on Rays motor I will be using the earlier pre smog head, 12G940 so we keep the "earlier feel" to the entire 1963 "project Spridget".
Some of the early 1275s were higher compression from the factory, but that's no big deal if you are rebuilding, you can use the AE21253 pistons with it's higher compression height and make it a higher compression engine for the cost of a set of pistons, cheap horsepower. With just the addition of the AE21253 pistons you can get a 1275's comprtession ratio to around 9.5 to 1 with a virgin block and head deck.
The great thing about a 1275 is you have so many choices in aftermarket goodies, you can go hog wild like we are doing with Ray's motor or you can pick and choose the best bang for the buck, and get good improvement rather cheaply.
Side note: Some 1275 engines do in fact have mechanical fuel pump blanking plate, Ray's engine, that I'm building right now is a late 72-73 block and it has mech. fuel pump blanking plate, on Rays motor I will be using the earlier pre smog head, 12G940 so we keep the "earlier feel" to the entire 1963 "project Spridget".
Some of the early 1275s were higher compression from the factory, but that's no big deal if you are rebuilding, you can use the AE21253 pistons with it's higher compression height and make it a higher compression engine for the cost of a set of pistons, cheap horsepower. With just the addition of the AE21253 pistons you can get a 1275's comprtession ratio to around 9.5 to 1 with a virgin block and head deck.
The great thing about a 1275 is you have so many choices in aftermarket goodies, you can go hog wild like we are doing with Ray's motor or you can pick and choose the best bang for the buck, and get good improvement rather cheaply.