UN1 selection problem - rod change - no 5th.

[RichardH]

Hi again folks.

Sudden loss of 5th gear today. Selection of all other gears is fine, but gear selection will not move past 3/4th position.
It is as if 5th gear selection is out of alignment .
I have seen mentioned the removal of the rear cover. Is this easy to do, to check the selection mechanism, or is there a different procedure I can do?

The car is driveable, but I dont fancy taking it far with only 4 gears.

Any help/ideas welcome.

 

[Graeme Stebbing]

hi Richard, you have a PM
regards
Graeme

 

[RichardH]

Thanks Lambo.

I think I might be ok there, but will near it in mind.


Can anyone tell me what I need to do?
I have no problems working on gearboxes, but not having touched a UN2 before, would rather not go in blind .

 

[Stephane Goria]

Hello Richard,

The only way is to remove the rear cover. Nothing tricky over this as it is clearly only a cover (ie not holding any bearing or so).

You will then need to use a new paper seal or directly a bend of loctite 518 when you will do the reassembly.

You need to remove all bolts and to not forget to remove the bolt maintaining the 5th gear fork + ball + spring.

Then you will have access to 5th gear assembly and all forks. Then it will be possible to know what is going wrong.

Post a pic and we will help.

As long as it only 5th gear fork, normally whatver the problem it should be fixable just removing the rear cover, no need to open the full gearbox.

Best

Stephane

 

[Malcolm]

My suggestion is to disconnect the gear linkage and determine if the non selction is due to causes within the box or outside the box. With gear rods off, can you now select all gears (mole grips on selector bar)? If yes then your rod system is out of aligment. If not then you need to go into the box. Whose solid rod sytem do you have? If the guides have become loose deep inside the car then that can cause misalignment.

 

[Mick Ridley]

Richard

This may help if you have to dismantle the rear housing

http://www.renaultalpineownersclub.com/Gearbox%20Manual/MRBVUN.pdf

mick

 

[RichardH]

thanks for the links and offers of manuals, but I do have copy.
It seems simple enough (famous last words). Its just attempting something new.

will keep you informed.

 

[Keith Stafford]

Richard, as Malcolm suggests, although without removing the linkage, firstly you could try using a second pair of hands to push (or pull) the selection bar to the fifth position, then see if when the selection bar is 'forced' in can the gear lever move to the fifth position. As I'm sure you know, all you need is a small amount of play to develop in the linkage and she's out-of-whack. Then disconnect and try as Malcolm suggests. My gear selection is a based on a tombola. Keith

 

[Phil]

Richard:
I too would echo what Malcolm and Keith mentioned....I have seen linkages that would select reverse, but not 5th, and when "adjusted" would get 5th but not reverse.
A small amount of "slop" in the rotational aspect of the linkage rod can make a 1" side to side movement in the shifter and usually the culprit is a loose connection, worn u-joint, or the rod is not properly supported on its run to the gearbox.
Its the cheapest thing before going inside.
Most of the time I find the sloppiness to be where a thru-bolt connects two parts of the linkage, and that is easily fixed.
Cheers
Phil

 

[Malcolm]

Any helicopter joint knuckle thingy needs to have a decent size bolt through it and also be glued. If not over time they will play up. I can remember a long time back at an event at Bovington Tank test circuit when I was having gear selection issues (now all solved with Southern GT setup hasten to add) and was so thrilled to have hit the right gear at long bloody last, that I missed my breaking point and screwed up big time. Spun off the track fortunately went in between various tank traps (cubic metres of concrete and steel girder contraptions) and went on for miles rotating around and around. Was so far from the track I needed a marshal to walk in front of me to show me the way back to the track. Bounced around so much I triggered my 10G fuel cut off for the one and only time in 21 years of having the car on the road and track! Would have been way more than 10G if I had hit a tank trap thorugh.... So I like my gear selection to be spot on now as one less thing to worry over.

 

[RichardH]

I have had a problem with gear selection and have found a loose bolt where the machanism pivots outside the gearbox. I have now fixed this and adjusted some of the pivots, so that wear is not so critical. I think the problem that I now have is in the gearbox as the selector shaft will not move across to 5th.
Most of the selector mechanism uses rose joints, but the bolts going through the rose joints are not as good a fit as they could be ( a 7.8mm bolt going through an 8mm rose joint. The slack seems to be an accumulation of lots of "negligable" wear/ tolerances being compounded by the lever system, exaccurbating this wear to cause a sloppy selection system.

I have had the mechanism looked at by Southern GT, but this failure has happened within 300 miles.

 

[RichardH]

reet - took rear cover off today...

must remember to drain oil in future .

here are a couple of pics. cant see anything wrong with selector mechanism, but it could have moved when the cover came off.

is the fifth gear supposed to look like that - the teeth look a bit chewed to me?

 

[Stephane Goria]

Hi Richard,

From the pic, it doesn't seem there is a trouble from the links. The locations for the gear selector are well aligned. Even , if it is not the subject, specific attention to these locations that are clearly eaten on their sides, respect your H pattern and don't shift diagonnaly. Next time, your gearbox is on the bench, I would recommend to change them.

Anyway, back to your gearbox, all seems normal.

The only thing to test right now, is to pull the 5th gear hub to see if it engages. If it doesn't, most of the time it is because the inside spring is broken and then a part of it, is blocking any move.

If the hub moves freely, then your problem is elsewhere. Not inside the gearbox, but have a look at the rear cover :

Gear selector has to slide fully from letft to right (spring fully compressed),
nothing should be inside the hole where the 5th gear links stands.

Cheers

Stephane

 

[RichardH]

Does anyone know if Chris Cole has an e-mail address?

 

[Ian Anderson]

I believe he does not use e mail.

He also had a multiple bypass earlier this year but was looking well at the club AGM at Stoneleigh

Best way is to give him a ring

Ian

 

[RichardH]

thanks Ian.

I found his membership email, so have tried that for starters.

Good he is recovering.

 

[Malcolm]

Dave Parker at Bordon Tyre and Exhaust has done a huge amount of Renault box work for GTD40 competition guys in the past if you can't get hold of Chris. He knows a lot about them having used them himself in his car. He also knows every trick and mod going.

 

[Chris Co]

reet - took rear cover off today...

must remember to drain oil in future .

here are a couple of pics. cant see anything wrong with selector mechanism, but it could have moved when the cover came off.

is the fifth gear supposed to look like that - the teeth look a bit chewed to me?

Wrong Chris Cole, However, it would seem to me the whole 5th gear synchro is "shot" and it looks like from only 1/2 engaging. Top photo, (TIP) the 5th gear is the gear (bevelled / large) on the right. the synchro engage(straight cut) gear, is on the left and this is the one you describe as "a bit Chewed" to put it mildly. Compare similar gears,synchro rings, synchro hubs and baulk ring on another gear and you will soon see the marked difference. Did you miss a gear change going into 5th under load?
Synchro hub looks "rounded" it should have the inverse of the gear profile and instead of teeth there sems to be only bumps.
Lucky, it is the easiest gear/synchro to change.
PS. buy a workshop manual and have a red hot go at it yourself.
Cheers
Chris ( I haven't had the triple by-pass yet but its coming)
PS, I have a ticket for a ride in P1018 and I can't wait.

 

[RichardH]

5th gear and selector now removed and will be on its way to Chris Cole (the correct one, not the guy in NZ!!!!! - Sorry ) for him to check prior to refitting.

I have a workshop manual, so that helps

Oh- and apparently Chris had a quadruple!! bypass, but says he is now fine .

 

[RichardH]

Rebuilt (at last), but what oil do you recommend for use in the Renault box? I see that Castrol TAF- X is what is OEM spec, but I have seen Syntrans mentioned as well as "standard" EP75w90 GL4 & GL5.
It is a road car, so not abused.