I would appreciate if anyone could advise if the following part numers for the cylinder head for a 1953 B33 (plunger) are interchangeable:
Part numbers 65-1226 and 65-1704. I understand that sometimes the castings are different by 1 number so could be part numbers could be 65-1226/1227 or 65-1704/1705.
In particular, are the cylinder head components directly interchangeable between these two cylinder head part numbers, eg: valves and guides, rocker assemblies, etc ?
Cheers
Bruce
The head 65 1704 was the new for 1953 season one with larger fins than the previous 65 1226 head and 1704 goes with a barrel with larger fins. The numbers in the parts book are usually the number for the head with guides or "fixed fittings".
Julien, thanks for your feedback and that back-story about the 65-1704 vs 65-1226 cylinder heads makes sense, understood and cheers.
I guess that's a similar back-story to the original cylinder barrel part number 65-1229 (listed for years 1949 to 1952) which had smaller fins and was subsequently updated to cylinder barrel part number 65-1707 (listed for years 1954 to 1957) which had larger fins........if I understand correctly ?
So presumably the 65-1704 cylinder head with the larger fins would be best matched with the 65-1707 cylinder barrel with the larger fins..................but are you aware if the cylinder head 65-1226 with the smaller fins could be mounted on the cylinder barrel 65-1707 with larger fins, ie: are the two cylinder head versions dimensionally compatible........ and/or visa versa ?
Reason for my questions is that my existing 65-1705 cylinder head (ie: with the larger fins) has a small internal crack at the carb inlet housing and I have the opportunity to buy a 2nd hand 65-1226 cylinder head (ie: with smaller fins). I believe the 2nd hand cylinder head is ok but has some fin damage in 3 discrete locations, which although not ideal should be ok. Might be worth noting that I am located in South East Asia when the climate is hot so the larger fins may be a small benefit although I am not expecting to work the old girl that hard.
And for clarity would you be aware if the internal "fittings" (valves, valve guides, rockers etc) in the parts book are fully dimensionally interchangeable between the 65-1704 and 65-1229 cylinder heads ?
Cheers for your help, much appreciated.
Bruce
Certainly the valves and guides and rocker spindles are the same part small and big fin. I dont know the answer to small fin head on large fin barrel.
I am very sure that a small fin head will fit on a big fin barrel although it would look a bit odd. All the component parts are the same; piston, valves, rockers etc. The only potential difference could be the spigot joint of the barrel to head but I think this is extremely unlikely.
Agree with Derek.
Heads and barrels are interchangeable, it is just the aesthetics
Same with B31s (I had one with mixed!)
I believe all the valve gear except the valves is interchangeable between the 350 and 500
Not sure if 500 pre 53 valves are same size as post (I only have 54/55 B31/33 parts book)
Thanks everyone for you feedback and knowledge sharing, much appreciated.
I have the two parts books for the 1949 to 1953-3 and the 1954-1955 models and it appears that all the cylinder head interhals/"fixings" have the same part numbers but I will continue my research.
Cheers for your help.
Bruce