Technical Help Identifying 100 Series Engine

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Technical Help Identifying 100 Series Engine

Ottocentocinquanta

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Hello, have a 100 series engine that is most likely not in the chassis that it started in.

It is a 100GL stamp block.
Spin on oil filter, under the dipstick, on the exhaust side of the engine.
The water pump does not power a mechanical cooling fan for the radiator.
Did some searching and got a few leads saying this is a Fiat 127 engine, but not sure of this.
The engine is currently in a 850 Spider...
What do we have here? Need a few replacement parts and it would help knowing what this engine is.
 
100GL.000 was the original 903cc ohv 127 engine. Have you got the full engine code rather than just 100GL to try to find the exact version?

Many 127 engines were put into the 850. They have to be made to run backwards of course for the 850. (y)
 
Thanks for the reply Palio.
"100GL FIAT" is in raised letters next to the dip-stick, that is the only markings noticed.
Unless there is another stamping that I didn't see, could look in the morning when there is light.

There are some custom things done to this engine;
Custom 4-1 header, Mallory Distributor, lightweight crank pulley, two piece & finned oil pan, and bigger carb with a JOEL adapter.
The guy that sold me the car used to be a Fiat nut and told me about getting some engines to run backwards for the 850 Spider chassis. The Spider runs the opposite direction from the 850 Sedans and Coupes.
However we talked about so much and so long ago that it slips my memory now.
 
Took a look at the engine

On the waterpump side of the engine there are three freeze plugs. Between them are the letters A & R

So looks a bit like this:
(O) [A] (O) [R] (O)

And on the same side of the engine, close to the head, in raised characters on the block, close to the timing chain cover... are the numbers 4388294
 
The no. cast into the side of the cyl. block (4388294) is a casting no. and might also be the part no. of the block.

The engine no. (iirc) is on the machined surface of the cyl. block just above/beside the timing chain cover and below the head gasket surface.

Afaik, all the 850 (817, 843 & 903cc) engines regardless of capacity and model fitment ran counter-clockwise. The 600 (633 & 767cc) and 127 (903cc) while similar in appearance and design to the 850, ran clockwise. I've heard of 127 engines being modified to run counter-clockwise using parts from the 850 engine.

The 850 Coupe and possibly Spider engines were fitted with a very good design of alloy one-piece finned oil pan - it incorporated an anti-surge collector box with a hinged door. These models were also fitted with a 4-1 header as stock.

AL.
(Fiat dealership Mechanic here 'back in the day')
 
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There was more numbers on the machined surface, same side as the timing chain cover, crank pulley, etc.
Much finer engraving so wasn't able to see it before shining a LED flashlight on it.

It says:

A112 A2 000
0045000
 
The numbers A112 A2 000 refer afaik to an Auto Bianchi /Lancia engine, of 1059cc capacity, power output 51kW (66bhp). But I vaguely remember that all Fiat type 1059cc engines were OHC (overhead cam)?

Are you sure the number isn't A112 A 000 or A112 A 500, both of these are 903cc, OHV engines producing c.40 bhp.?

As 'Palio' said above, 100GL on the cylinder block is a 903cc Fiat 127 engine. The 127 had a mechanical fuel pump mounted on the timing cover and did not have the hole in the cylinder block below the exhaust (close to the timing chain cover) to mount a camshaft driven fuel pump as on the 850 original engine. It's possible that the 127 timing cover was swapped for one from the 850 Spider to allow for fitting the 850 engine mounting bracket. So, where is your fuel pump? Or is an electric pump now fitted?
Your water pump and fitment of an oil filter suggests a 127 engine. The 850 Spider/Coupe had no oil filter canister, it had a centrifugal filter incorporated into the crank pulley.

AL.
 
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This 850 Spider now has an electric fuel pump.
Instead of the centrifugal oil filter (not needed) there is a lightweight crank pulley.

The timing cover does look just like the 850 timing cover seen on a sport spider.
Instead of there being a fuel pump on the block, there is a spin on oil filter in it's place.

The block is stamped A112 A2 000

Looked that up online and pointed to the Autobianchi A112 Abarth. A sister car of the 127.
A112 engines are listed as OHV

A112 A1 engines produced from '71-'75 - 58 HP
A112 A2 engines produced from '76 on - 70 HP
Also read that both engines were sold at the same time until the A1 was phased out.
Also read about the A5 being an economy model making 42 HP.

This car is a '68 850 Spider.

Have another one being restored at the same time that is a '71 850 Sport Spider.
All looks very similar minus the oil filter differences, spin on vs centrifugal. And the fuel pump, electric vs mechanical.
 
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