Long Stroke Crankshaft Interchangeability Question

[citroenthusiast]

I am considering rebuilding another long stroke engine. This time it is for a friend who does not want the car sitting without an engine for 6-12 months while the engine is being rebuilt so I offered the possibility that I would rebuild a core I have on hand then swap the rebuilt engine for the worn out engine. The car is from 1964 with the long-nose crankshaft and harmonic balancer. Unfortunately, the cores I have both have the short-nose crankshaft with the closed timing cover and no harmonic balancer. Looking at parts manual (No. 466) I found that there were no fewer than 5 different crankshafts before 1961, the last being the one with the long nose for the harmonic balancer. My question is, can a long-nose (Post-March 1961) crankshaft be fitted to an earlier block? Has anyone here successfully done so? If so, then it may be feasible to source a crankshaft, rebuild the engine and simply install the timing cover as part of the engine swapping process.

 

[David S]

Did the block and bearings change? The conrods changed around 1960-ish and you might want to check if that also affected the crank journals. Have a look at the thrust washer and thrower setup as they were changed. You might revisit Shane's thread on the broken crankshaft.

 

[DoubleChevron]

Did the block and bearings change? The conrods changed around 1960-ish and you might want to check if that also affected the crank journals. Have a look at the thrust washer and thrower setup as they were changed. You might revisit Shane's thread on the broken crankshaft.

I was just thinking about that thread too. It all sounded like it gets complex quickly if you try to mix and match parts.

I think Gerry and possibly Buttercup bob will know the differences off the top of there heads! We will just need ot wait for them to read this

 

[gerrypro]

I have not had much to do with later long-stroke cranks. I drove a 1911cc DS19 Pallas but never had the motor out. I had an early DS19 block and crankshaft which I gave to Roger Brundle before he passed! So I cannot answer this question.

 

[citroenthusiast]

Thanks guys. I have been studying manual 465 and it shows four possible combinations, old crankcase with 35.99mm rear bearing saddle; new crankcase with 37.7mm rear bearing saddle; old crankshaft with 44.1mm long rear journal; and new crankshaft with 42.3mm long rear journal. In each case it seems to be a matter of selecting either a thick bronze thrust washer or a thin white metal thrust washer and possibly shortening the locating pin for the thrust washer. I think the "new" crankshaft is the long nose one with the harmonic balancer but I can't tell for sure, since the manual talks about crankshafts after January 1961 but the balancer was not introduced until March 1961, so hoping someone could confirm I am not going to get halfway done and realize it is impossible....