18 replies to this topic

[Staddon]

Apologies if this is in the wrong topic, couldn't find one relating to this type of question. 

 

Just wondering fi any one could identify the engine for me as i believe it to be a 998 but one of the guys at the garage i bought it from says it is a 1275 engine, yet it has a engine number which says its the 998... 

 

Any help would be great, thanks in advance! 

 

 

[Spider]

It's not a 1275.

 

It is a small bore block but has a 1275 head, so could be anything from 850 to 1100.

Edited by Moke Spider, 16 June 2015 - 09:38 AM.

[Mini Manannán]

If you can read the engine number put it in here: http://www.guess-wor...Tech/engine.htm

[Staddon]

Ahhh, okay, engine number states a 998, so must be that with the 1275 head! thanks guys!! 

[gazza82]

It's not a 1275.

 

It is a small bore block but has a 1275 head, so could be anything from 850 to 1100.

 

What makes it a 1275 head Spider?

[Spider]

 

It's not a 1275.

 

It is a small bore block but has a 1275 head, so could be anything from 850 to 1100.

 

What makes it a 1275 head Spider?

 

 

 

Ah, well,,, only a Spider knows

[Spider]

but, to spill the beans,,,

 

I can tell buy the Thermostat Housing angle and while somewhat hidden behind the coil bracket, the angle of the heater take off

Edited by Moke Spider, 16 June 2015 - 11:06 AM.

[gazza82]

Housing could have been replaced?

 

I would have thought the best way is to look at the numbers in the casting? Rocker box will have to come off.

[Icey]

Housing could have been replaced?

 

I would have thought the best way is to look at the numbers in the casting? Rocker box will have to come off.

Housing could have but the angle of the heater outlet couldn't. Usually the 998 outlets are parallel to the rockers, 1275 at an angle. BUT! I don't know if there are any variants that break that rule so I'd agree that the casting number is the best indicator.

[nicklouse]

Housing could have been replaced?
 
I would have thought the best way is to look at the numbers in the casting? Rocker box will have to come off.

Housing could have but the angle of the heater outlet couldn't. Usually the 998 outlets are parallel to the rockers, 1275 at an angle. BUT! I don't know if there are any variants that break that rule so I'd agree that the casting number is the best indicator.

1275 (and the S) heads have a different stud patten for the thermostat. and the heater take off. that is how you tell the thermostat outlet points away fron the rad on a big bore head and to the rad on a small bore head.

there is also as larger gap (and different angel) between the heater take off on the big bore than the small bore.

[69k1100]

http://www.theminifo...arage-clearout/

The thermostat almost touches the rocker cover on a small bore head.

[gazza82]

OK .. I defer to the experts! Wonder if that means the block has been pocketed?

 

I've only got two 12G940's I can look at (one flat surface, one A+ sculptured) until my old A35 returns to it's rightful home ... then I can look at a small bore head (948cc) although that has a 998cc Riley Elf thermostat housing with temp sender take-off now too.

 

Suppose I could have trawled fleabay or google for pics ..

Edited by gazza82, 16 June 2015 - 02:51 PM.

[Spitz]

Obviously a 1275 head.

...And having twin HS4 carbs, I hope that bottom end is really built up, or that's way too much carb on a small bore

[Staddon]

Obviously a 1275 head.

...And having twin HS4 carbs, I hope that bottom end is really built up, or that's way too much carb on a small bore

doubt it, gonna take it out, strip it all down and figure out what needs doing.. 

[Staddon]

okay, so if the 1275 head hasn't been pocketed, what would be the best thing? source a 998 head, as i won't be able to pocket it and to have it done professionally can cost quite a bit? would a non-pocketed head be bad? 

 

and say if it was over-carbed, which parts of the bottom end would need upgrading if the engine was stock, or replacing if they are just old parts and likely to fail?

 

sorry if these are dumb questions - not really experienced with this stuff yet! ;) getting there though. 

Edited by Staddon, 22 June 2015 - 07:26 AM.