Datsun B310 (New Sunny) Gearbox stuck in reverse (Read 164 times)

[garyfrogeye]

Hello from me.
Please note that no UK Datsuns were hurt in the fitting of my gearbox.
Many years ago I imported a Datsun Gearbox New Sunny (B310) from the USA and it has been happily working well in my Sprint 1958 Frogeye Sprite (boo-hiss) for ten years. During that time it has been fantastic traveled many thousands of touring and competitive miles.
But yesterday on a track day, it let me down.
It has stuck in reverse. in 1st and 2nd it seems to be fighting itself and will just stall if the clutch is lifted, in third (it wants to reverse) it will disengage but only with the clutch down. In fourth fifth and reverse, the car will move backwards even with the clutch pressed fully down. I know the clutch is ok though.
Can anyone help?
If you feel that I have no right to be here as I don't have a Datsun (though I used to have a Datsun 1600 and a 2600c estate) the moderator can remove my membership.
Thanks in advance

Gary

[Al Ramone]

Obviously a selector problem. your gonna need to strip it to find out whats fallen off or jammed up.

I think someone may be able to offer you a good 4 speed in exchange for your box thou....

[datman]

I;ve got a brand new still in the wrapper gearbpox but its 4 speed. 5 speeds are hard to get but Im sure a gearbox specialist could find out whats wrong with it and the replacement parts SHOULD still be available.

[garyfrogeye]

Hi alramone and datman,
Many thanks for your replies and the offer of a four speed. I'd hate to lose the the fifth gear so I will do all I can to get this one fixed. To get to the gearbox on a Sprite is an engine out job which I won't be able to do for at least 3 weeks! but I'll feedback when I've had a chance to look at it.
Many thanks
Gary

[garyfrogeye]

Just an update (and not much one of one at that). Finally managed to get the gearbox out, which is also an engine out job for me. Nothing external damaged, but I didn't imagine that there would be. As there seems to be no way of inpecting the internals without taking it apart, I still can't tell if something's broken or just come loose. On a positive note, the oil was relatively clear of swarf when emptied and thankfully no lumps of metal at the bottom.
Does anyone know of someone experienced with Datsun gearboxes anywhere near London/the South East?
Once again, it's a B310 box.
Many thanks in advance

Gary

[RatDat]

They're pretty simple little gearboxes. I have a service manual that covers the five speed which I can scan if you fancy having a go yourself. It sounds like one of the selector forks has come adrift.