Gearbox Trouble

evilally · Post by **evilally** » 08 May 2009, 21:26

Hi guys, I posted this on another forum but appreciate any input from here.

Well, my old beast has finally given me some trouble after 20,000 miles of good motoring. Tonight it got stuck in 3rd, and won't change. I can move the leaver backwards and forwards between 3rd and 4th, but it stays in 3rd. It's always had synchro issues with 3rd as it crunches gear changes, is this related?

I've also got a working box from a 1.9td 306 in the garage, is it time to fit this?

Post by **CitroJim** » 08 May 2009, 21:50

Well, about the only thing that will cause that is if either a selector fork has broken, something has gone wrong with the selector mechanism or the 3rd/4th synchro hub has failed spectacularly. It's unusual but you can tell definitely if it is stuck in third as if you try to select any other gear, the 'box should lock up solid as two gears try to engage at once. This may not happen if you try to engage 4th but should if you try to go to 5th, 1st or second as different selector forks are used.

I assume you've checked all the external linkages are in place and OK as a broken rod can give rise to this feeling.

The sleclection mechanism is very robust and the mechanism from the selector shaft is double roll-pinned and the 5th gear selector is also roll-pinned to its shaft.

Have a look here for some pictures of the selector mechanisms.

One thought is that it might actually be stuck in 5th as it's conceivable that the roll pin holding the 5th selector fork could have let go. If it is, that can be fixed in-situ.

Another possibility is that the detent spring on the 3rd/4th selector fork may have broken and yet another one is a broken synchro spring on the 3rd/4th syncro hub that may have gone walkabout and caused the hub to jam in 3rd. That spring breaking normally only causes a crunchy third, which it looks as if you've had for a while so it's possible.

Upshot is, its repairable but if you have a good spare, time to pop it in. Not sure if the 306 ratios sufficiently close but it'll do until you fix the broken 'box.

It will be interesting, in due course, to know what failed.

evilally · Post by **evilally** » 08 May 2009, 22:50

Thanks (again) Jim. I'm not too handy with the spanners but trying to learn. I've opened a couple of tins and am looking over the section of Haynes that deals with checking the linkages, will do this tomorrow. The only thing I can say for sure is that it's definitely stuck in 3rd, not 5th. Thanks again, I will report back when I know more.

evilally · Post by **evilally** » 10 May 2009, 14:32

Hi Jim, had a look at the car today. A linkeage had popped off (I feel like such a newbie). I put it back and the gears were changing again, but there's a lot of play in the ball joint. I'm going to order a new linkeage/rod thingy from the stealers tomorrow, they're only £13. Thanks again.