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View Full Version : Picked up the '72...already need help w/gearbox



GreatWhiteNorth
07-27-2009, 02:37 PM
Hello all,

I picked up the first of my two newly acquired Rovers on Saturday night, a '72 Series III 88. It's in fantastic shape, and I'll get extensive pictures up of it soon. The prior owner told me that he thought the shifter needed a little "adjusting", since it had gotten a little tight going into second gear. Luckily the trans has never popped out of gear, and there is no crunching or grinding noise coming from the gearbox, so I think all that is OK and there's not an issue with the syncros or gears. Anyways, I went through the entire ordeal of unplating the floor pans and removing the seat to take the top cover off the gear box, and inspected the selector rods. I couldn't really find anything out of sorts with them, so I loosened the bolt holding the fork to the 1st/2nd shaft, and slid the shaft back a little, and then tightened it back up. I put everything back together, and now it's stuck in a forward gear, although I'm not certain which one. I do know that I put the springs back in the wrong locations, so I'll fix that this time.

If anyone could give me some advice on what the selector rods should look like when lined up in neutral, as well as any info or links on how the selector rods and forks should be adjusted, I would greatly appreciate it. It's back apart and I have everything laid back in the way I think it should be, but something just doesn't seem to be right. First and second gear seemed to be engaging fine before, but third/fourth rod didn't seem to move much at all. Can't tell if there's an issue with the detents or springs or check balls, etc. But something's just not right. Hopefully someone can point me in the right direction.

Thanks guys.

GreatWhiteNorth
07-28-2009, 01:27 AM
OK, got the gearbox to shift again, but something still doesn't seem right. The 1-2 shift is ok, a little notchy into 2nd but not too bad. The 3-4 shift feels really good, and the shift into reverse feels good as well. The problem I'm having now is the 2-3 shift. I cannot go from 2 to 3 without finding neutral and then shifting to 3rd, and finding neutral can be a bit of a pain at times. Is it supposed to shift like this? Is there a synchro between 2nd and 3rd gear? Would it make things any better if I adjust the fork back farther on the selector shaft? It just seems like it shouldn't be this hard to shift...

LaneRover
07-28-2009, 07:02 AM
Not sure about the innards of a trannie but there is definitely a synchro going from 2nd to 3rd.

Mine shift pretty easy - even the older trannies with no synchro on 1st or 2nd.

Brent

GreatWhiteNorth
07-28-2009, 11:08 AM
I think I'm going to take the top plate off the gearbox one more time and slide the 1/2 shaft back. I don't believe the gates are lining up like they should in neutral...I think the 1/2 is way too far forward, making a very small space for the shifter to slide over to the 3/4 shaft. Hopefully that will help...

LaneRover
07-28-2009, 12:08 PM
Not sure if this helps but on my Rovers the range of motion between 1st and neutral is much greater than it is between 2nd and neutral.

GreatWhiteNorth
07-28-2009, 12:19 PM
Not sure if this helps but on my Rovers the range of motion between 1st and neutral is much greater than it is between 2nd and neutral.

I will keep that in mind. I think what is happening is that the 1-2 shaft is slid forward in the fork's collar, and it is not lining the neutral detent up with the detents on the other two shafts. Hopefully if I slide it back a little and get the detents lined up perfectly, that will take care of the problem. Plus I think sliding it back a little will help align the selector cups on the ends of the shafts better.

GreatWhiteNorth
07-29-2009, 11:25 AM
Well damn. I pulled the top plate back off last night after I was sure the trans was in neutral, and everything was lined up perfectly. I made the slightest of adjustments to the 1-2 shaft, but that was all. Cleaned everything up, applied some oil to the detents and balls, and put it back together, making sure the springs were in the right way. No luck. Still very tight going into and out of 2nd.

LaneRover
07-29-2009, 11:48 AM
Forgive the stupid/obvious question, I have no idea if you are familiar with old vehicles or if this is your first.

Have you checked the oil level in the transmission? I remember reading about some guy in England who was complaining about how horrid his transmission was in his 90, that it had gotten progressively worse over time. The shop went to drain the oil and there wasn't any!! They filled it up, crossed their fingers and suddenly everything worked fine! Afterwords the guy was a mazed at how great his transmission was and how smoothly it shifted.

I would first check the level of the 90wt gear oil (Square head bolt on the side) and if it is low add some oil and see if that helps. Put your finger in the hole and see if there is any oil on it when you pull it out to check the level. If your finger comes out red that means someone put transmission fluid in it and you need to drain all of it out!

After adding oil I would spin the transmission a bit by putting the transfer case in neutral and then running the Rover with it in gear. After a bit of time 30 sec? 1 minute? start to shift between 1st and 2nd.

If the 90 wt oil had been REALLY low and adding oil helps I would run it for a week or two and then change it to get rid of any gunked up crap that new oil might dislodge.

Unfortunately the seemingly stupid or obvious questions sometimes remind me what I forgot to check in the first place!

GreatWhiteNorth
07-29-2009, 12:01 PM
That's a good point, but the fluids in the truck had all been changed before I got it. Plus, I could see the fluid level was up to the sight plug when I had the top plate off. Wish it were that easy.

greenmeanie
07-29-2009, 01:48 PM
From the series III manual you want to assemble the 1st/2nd fork with the pinch bolt in the groove closest to the front of the shaft. You want to center the fork on the groove. On reassembly make sure the fork slipper is riding in the groove on the gear.

Set the clearance on the reverse stop to .005 although I would really expect this to affect selecting all gears.

Look at the ball in the base of your gear lever assembly and make sure it is not sloppy or missing the plastic ball that is on the end. The IIA has a steel end with a groove for an o-ring but IIRC the III is a plastic end. Make sure the reverse shift gate/flap device is not getting in the way too.

Finally, drain the oil and look for yellow metal that would indicate a knackered synchro ring.

GreatWhiteNorth
07-29-2009, 02:24 PM
From the series III manual you want to assemble the 1st/2nd fork with the pinch bolt in the groove closest to the front of the shaft. You want to center the fork on the groove. On reassembly make sure the fork slipper is riding in the groove on the gear.

Set the clearance on the reverse stop to .005 although I would really expect this to affect selecting all gears.

Look at the ball in the base of your gear lever assembly and make sure it is not sloppy or missing the plastic ball that is on the end. The IIA has a steel end with a groove for an o-ring but IIRC the III is a plastic end. Make sure the reverse shift gate/flap device is not getting in the way too.

Finally, drain the oil and look for yellow metal that would indicate a knackered synchro ring.

Thanks for this. I think someone installed a Series II shifter, as mine has a steel ball on the end. Though it is missing the O-ring. I've had the fluid out and everything looked good.

GreatWhiteNorth
07-30-2009, 11:21 AM
Took it on a test drive last night, and I must say it shifts much better while driving than it does while sitting in my garage. Feels pretty good and smooth in all gears now.