1vj engine assembly...gearbox goes tight when mating side casings

[charliext1vj]

Help please..
Trying to assemble split casings...have replaced.. sprocket shaft and 3rd and 5th gear.....all bits were from another 1vj engine....engine goes together as it should with gear box working before adding other case. When adding other case loosely bolted together...gear box working...but as soon as torqued the gearbox drive shaft and selector goes stiff. Ideas please?.... happy new year

[donnybach]

Are the bearings fitted all the way home?

[motorang]

Best to assemle bearings in hot casing (100 °C), then let heat crawl into the bearings and put cold shafts in, the temp difference helps with seating.

Andy

[charliext1vj]

The bearings were not removed...just pulled out shafts and selectors...and replaced the gearbox shaft like for like....I will try and measure them up...but it is only torque that affects it...so close so far..will let you know!

[charliext1vj]

Result..... split the casings again...removed the gear box etc, tapped all the bearings to hear if they were solid against the casing, did a thinner smear of assembly lube, paired casing dry and all worked fine, wellsealed casing halves and all appears fine! Thanks for the advice and support.

[donnybach]

Cool. You can post is a video when she’s running.