Over maybe the past month my gearbox has started occasionally jumping out of first gear. I've tried holding the lever foward into first gear and can sometimes feeling the kind of pulsing of the force pushing the lever back. My knowledge of gearboxes is aero so I'm kind of resigned to getting some sort of exchange replacement sorted after the summer. Most likely a clutch replacment at the same time. so step one I guess is finding out what I've got fitted. Is there any specific place to look on the gearbox and housing to find out what it is ? Thanks
As usual, start with adjustments, check the shift coupler etc. Then take the nose cone off the gearbox , look for broken guide bracket for the shift relay arm, its a strip of metal bolted to the casting that has two "ears" that guide the relay arm. They crack. Also check the "donut" that goes on the end of the "hockeystick" where it goes into the eye on the end of the relay lever that actually pulls and pushes the gearchange rods coming out of the gearbox itself. They were originally made of hard plastic and they wear so that gearchange becomes more and more vague in general. The hole in the middle gets bigger until you are changing gear by pushing metal to metal ..(I had to deburr the relay lever to get the new donut in as the metal to metal contact had bashed grooves in the casting of the lever). Probably worth changing the donut now you have the nosecone off anyway. It could be accumulated wear in the linkage that means you are only just engaging first and its popping back out. This picture was because the main bearing on mine was loose (4th gear issues, clunking) ..but it shows the bracket and the relay lever and where the donut sits. I was able to crack the gearbox open and the gasket stayed together. Bears Motorsport who fixed mine later doesnt use gaskets just a bead of appropriate silicone, which doesnt leak, so if the gasket fails, its up to you how to seal it up again. Gasket or sealant. On later "091" gearboxes that big bearing is locked in place with a flat steel key engaging in a pocket in the bearing that stops it spinning and also stops it going forward. On my gearbox that bearing was spinning and had chewed its way up to about 2mm forwards.. it should be flush with the casting. Even in that picture it looks like its a bit higher. .
This ^^^ (Not everything) But adjustment is key ... My gearbox isn't the best and started jumping out of first recently , cured instantly by tightening the cable a couple of turns . This may or may not be your problem but worth try and cheaper than a recon box .I'm not saying it cured the problem as the box badly needs a rebuild... Sent from my SM-G960F using Tapatalk
Years ago I was looking to buy a van, the guy selling it said you had to keep pushing the gear stick forward, to keep it in first, otherwise it jumped out. I took it for a test drive, and he was right, but not a great sales pitch. His sales technique got worse when he said he'd have it fixed, if we paid for the work. We didn't buy it. Our van started to something similar a while back, sort of 'fell' out of first rather than jumped, and difficult to find and engage second. Replacing the gear shift coupling solved both problems. Worth checking before going the full hog on the gearbox. The replacement coupling had virtually no play in it, whilst the old one was very worn and sloppy.
Just to add I did some of the basic stuff to improve the linkage, changed the front plastic guide bush and a new coupling at the back. I’ll be moving guide plate under the gearstick mounting around a bit to see if that helps next…
Maybe you " missed" the middle of the dimple in the gearchange shaft coming out of the gearbox with the point of the screw and now its able to move around in the hole as the middle of the dimple is deeper than near the edges of the dimple.
Could Maybe… I recall it was one of the places that had wire retainer same as the coupling at the back…seems ok… Which does seem a whole lot more oilier than when I replaced it … i replaced nylon bushings on 2 places at the same time last year…
If you have the gearbox out , change the bushing and the lip seal that goes on the gearchange shaft where it goes into the gearbox nose cone. That will help with the gearbox oil getting onto the shift coupler. Also that does look like the stock style coupler- they can get wobbly very rapidly though usually its the collar that comes loose from the cage or the roll pin gets battered- that makes it harder hitting 1-2 or 3-4 as the twist in the gear change rod gets taken up as slop in the coupler. Fore and aft less change with coupler wear, but if the gearbox needs 100% movement to go into gear and you can only give it 90% maybe still a problem.
Still in the van I've afraid, might look into doing something after TE...the coupler is actually the best I could find ... i got a kit including CSP coupoler. From memory the one I took off didnt seem like stock either, had red rubber inset blocks. Still messing around and checking full movement of stick transfers back.
We've all done it. I found my best mole grips lying in the road. And a perfect new huge non-stick frying pan.
Aye they are indeed mole grips. I was re-adjusting my clutch while underneath and checking all the gear linkage stuff. They are now on the table behind me... Been feeling a touch of clutch slippage past couple of days as well as the other things. This is mostly the reason I'm not averse just just changing to a recon unit.
The clutch isn't the gearbox, but if it jumps out of a gear best start making plans sooner rather than later.
In the event, a quick feel under Ian's bus showed the square headed screw in the dimple of the gearbox selector rod was loose. Some more time with an adjustable spanner, tightening by about a quarter of a turn, and a rewiring of the locking wire and the gearchange was a lot better. Its possible that because of the angle of the hole through the screw, as the locking wire was originally tightened up, it loosened the screw.
