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Themadmob
3rd June 2014, 08:20 AM
Hi All

Can someone tell me the main differences when ordering parts for my series 2 engine vs the series 3 engine.

Besides the carburettor and 5 bearing engine almost all the parts seem interchangeable ?

Thanks

Craig

JDNSW
3rd June 2014, 05:21 PM
There is no difference between Series 2 and Series 3 engines - but there were continuous changes from the introduction of the engine (1957 for the diesel, 1958 for the petrol) until it was superseded by the 2.5 in about 1984 in the 90/110.

For this reason you need not the Series (2 or 3) but the engine number, particularly the letter suffix, when ordering parts. Also, since the engines are interchangeable, the engine you have may not be original.

The only really major change is the change from 2 to 2.25l for the diesel in 1961, and the change for both engines to five bearing right at the end of Series 3 production (but very few of these came to this country). There were changes, for example to the exhaust manifold, the water pump, and the cylinder head, as well as many other detail changes, but mostly the parts interchange as assemblies if not individual components, and the engine you have may have parts that are different from when it was made.

Accessory changes are more noticeable, especially carburettor (Solex -> Zenith -> Weber) and generator -> alternator (This was with Series 2 ->3) and all sorts of emissions equipment that varied frequently but also with the market.

John

Themadmob
3rd June 2014, 08:34 PM
Whst a great response John ... much appreciated

reachjatt
3rd June 2014, 09:24 PM
Correct me if i am wrong. But one noticeable difference among II,IIA&III 2.25l engines being compression ratio 8:1 vs 7:1

JDNSW
4th June 2014, 06:26 AM
Correct me if i am wrong. But one noticeable difference among II,IIA&III 2.25l engines being compression ratio 8:1 vs 7:1

As I said, not a difference between Series. The petrol engine was available either 7:1 or 8:1 from very early in production (probably even in 1958). In Australia 7:1 remained standard at least until late Series 3. The difference in compression ratio does not change parts ordering except for spark plugs (and of course the head).

Note that the cylinder head may have been modified in service, so the engine number and the stamp on top of the head do not necessarily tell you the ratio!

John

Themadmob
4th June 2014, 07:57 PM
Thanks guys

incisor
4th June 2014, 08:35 PM
As I said, not a difference between Series. The petrol engine was available either 7:1 or 8:1 from very early in production (probably even in 1958).

pretty sure the early petrol 2.25l head can not be skimmed enough to get you the extra compression. dam sure i have read that in several manuals over the years.

JDNSW
5th June 2014, 05:41 AM
pretty sure the early petrol 2.25l head can not be skimmed enough to get you the extra compression. dam sure i have read that in several manuals over the years.

Correct, in a sense. Early 7:1 heads are a different casting that does not reliably have enough metal that it can be safely planed (but undoubtedly some have been!). My understanding is that the 8:1 head was available pretty much from the start - later heads used this same casting for both ratios, with less machined off for 7:1. Since standard production in Australia was 7:1 (I don't think 'Super' was sold then) almost all Series 2 and early 2a seen in Australia will be the original 'early' 7:1 head. Assuming they have the original engine and head!

John