Renault UN1 gearbox help

Hi Chaps,
Went to go out in my MDA a couple of days ago .... started it up and reversed it out of the garage. Ten minutes later jumped in and fired it up and it wouldn't select any gears including reverse which I had just used.
The whole mechanism seemed to be jammed.
Today I undid the last universal joint alongside the engine to free up the gear lever end of the shafting and that was all ok. The gearbox end (supplied by Southern GT) was still solid and after a lot of faffing around it seems as though something has happened with the selector inside the rear of the gearbox. I'm going to call Chris Cole on Monday for expert opinion but in the meantime if anyone has any knowledge as to what has gone wrong I would welcome some input.
Hi Steve,
Chris is the man for info and to sort your problem for you, he has done my gear box twice now!
I have had to take the box out & back in about 5 times now, if you like to give me a call could help with a couple of pointers?
01892 664803


Strange.....Mine has just done the exact same thing. Had it out for a blast, running great with no issues. Parked it in the garage then came out 2 days later and it's all jammed up. I spoke with Chris this morning and he said that you and I had both called him on the same day with the same issue!

It'll be interesting to see what it is.....I'm taking the rear end off the gearbox now (with a little bit of phone help from Chris!) If I make any progress then I'll let you know.
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Hi Mark ..... unbelievable, I bet Chris thought he was having some sort of strange dream!
I would be very interested to hear what you find when you get it apart as Chris couldn't really understand what has come adrift. My phone number is in the Club member listing if you fancy giving me a call. I'm not going to attack mine just yet as I've busy doing other stuff (getting ready for a house move).
Hi Steve,

I tried to find your number, but if you drop me a pm with it then I can give you a call. I've taken a pic, so hopefully this makes sense and might shed some light on your issue, as it sounds identical.


Time to complete the saga ....... with loads of input from Chris Cole and on the back of a similar experience from Mark (see above in this thread) and also a chat with Mick at Southern GT it was time to fix the problem. Here comes the twist ...... when I set about pulling the back off the gearbox it was necessary to remove the linkage and this revealed that two of the rod end bearings that support the final part of the gear shaft were seized solid. With the shaft on the bench it took a lot of effort to get the bearings off the shaft. However they were not rusty, they just seemed to be locked on as if they were a press fit. As we also know they need to be a nice sliding fit. Having cleaned all the parts the bearings were still not a clear sliding fit. I don't understand how this has happened - how can something have changed dimensionally.
I've now fitted new bearings and spent a long time with the shaft in my lathe with various grades of wet 'n dry getting the surface of the shaft silky smooth. It has taken over 2 days to completely resolve the problem.
Given that I've always kept the shaft clean and greased by the bearings I still don't understand why this happened.
I would like to put on record that Chris Cole has been fantastic in offering help and input. Thank you Sir.
Scary... Now I have one of these brutes, its something else to wory about! Excuse my ignorance of the gearbox, but is the oil used in the box critical? Does it lubricate the selector mechanism? If yes to these, might regular oil changes be an advisable preventative? In passing, ay recommendations as to oil grade, brand etc?