Silver century plus

[Dat999]

Hi Just a quick question. Is it possible to fit change the gearing ratio of a silver century plus from 4/1 to the 3\1 standard century. Basically I am looking to run the five blade hydro prob at higher gearing for a project this winter. Thanks in advance Dave.

[geofflena]

Seems not to me - to run the large prop you would need the large crankcase - as it would not fit the silver century.
I doubt one could mount a 35 crown in the large box - as the pinion would not line up - but if you dropped the pinion bush It might be possible ? You would need a longer reach on the driveshaft as well - if it could be done.

[Charles uk]

The most cost effective way of doing this would be to buy the entire bottom end of a silver century, water feed pipe, drive shaft, drive shaft tube, exhaust, water pump housing & lower unit, & swap the whole lot, your in Kent why not try Seagull Restorer?

[Oyster 49]

Not sure that the power head will generate the power to turn the larger prop at a higher speed?

[Charles uk]

I think you'll find it's exactly the same power head in every respect when you compare a century with a century plus that were manufactured at the same time.

Sorry Oyster I've just re read the question & it's not very clear, does he wants to run the 13" hydro fan on a 3.5:1 ratio box or the 9" 100 only hydro fan.

No ones racing in Kent are they?