T.Watts Posted June 10, 2012 Share Posted June 10, 2012 Right then, spurred on by the fact that Howard has borrowed the floor out of the gmc I have decided to drop the gearbox out and sort out 5th gear as have been running about to the past couple of shows minus 5th good job they weren't far away, all linkages etc have been disconnected and it is ready drop out bar the bolts holding it in Also is it worth dropping the pto box off of the gearbox? any ideas? Quote Link to comment Share on other sites More sharing options...
deadline Posted June 10, 2012 Share Posted June 10, 2012 The proper procedure for dropping the transmission is on TM9-801 page 288. The rebuild is in TM9-1801. A free copy of the TM9-801 is available at: http://www.tm9-801.com/tm9-801/index.php Unless you have a transmission lift, I would lessen the load by removing the PTO (you will at least need to remove the linkages and shafts, anyway). I haven't weighed the trannys, but I would say they are easily 100-150kg and not very easy to grab on to. Quote Link to comment Share on other sites More sharing options...
Pete Ashby Posted June 10, 2012 Share Posted June 10, 2012 The proper procedure for dropping the transmission is on TM9-801 page 288. The rebuild is in TM9-1801. A free copy of the TM9-801 is available at: http://www.tm9-801.com/tm9-801/index.php Unless you have a transmission lift, I would lessen the load by removing the PTO (you will at least need to remove the linkages and shafts, anyway). I haven't weighed the trannys, but I would say they are easily 100-150kg and not very easy to grab on to. Deadline is absolutely right this isn't a rope around the shoulders job :shocked: you'll end up being pulled through the floor plate the weight distribution is not even. I've done it with a trolley jack, ratchet strap and small engine hoist it gives you the ability to move the box back out of the clutch hub while taking the weight on the hoist then lower away and pull out from underneath Pete Quote Link to comment Share on other sites More sharing options...
T.Watts Posted June 11, 2012 Author Share Posted June 11, 2012 Thanks for the pointers :-D was planning on dropping it out with forklift and a set of chains, just wondered if would be any easier to get the gearbox out from under the truck without the pto box attatched. Won't get a chance to do any more to it until weekend as in nottingham on a course at the mo. Quote Link to comment Share on other sites More sharing options...
shopnut Posted June 11, 2012 Share Posted June 11, 2012 If you have a jib for your fork truck, it could be used with a good lifting strop, also would be easier to remove the PTO prior removing gearbox. I do have a good used gearbox and clutch assembly, if you are interested, and a complete engine, that might be going a little to far. Regards Quote Link to comment Share on other sites More sharing options...
Degsy Posted June 11, 2012 Share Posted June 11, 2012 Before you remove the box it might be a good idea to remove the top of the box to see what is causing the problem. If you do remove it and lower it down, drop it onto a pallet, much easier to then move it around. Quote Link to comment Share on other sites More sharing options...
shopnut Posted June 12, 2012 Share Posted June 12, 2012 And its easier to remove and refit with the lid off and fill with oil, but don't drop any thing in there................... Quote Link to comment Share on other sites More sharing options...
deadline Posted June 12, 2012 Share Posted June 12, 2012 When you mean 'sort out 5th gear' what exactly is going on? Pops out of 5th? (Bent/worn shift fork/rail,poppet balls/springs missing) Cannot engage 5th? (worn gears, bend shafts/rails missing poppet balls/springs) Excessive noise? (worn gears, bad bearings/bushings) As long and the shift lever and the guide plate are working you cannot do much to the transmission with it still installed. Quote Link to comment Share on other sites More sharing options...
T.Watts Posted June 12, 2012 Author Share Posted June 12, 2012 well you can engage 5th but it keeps throwing it out of gear whether it is under load or not, you can hold it in gear but you can tell when it tries to throw it out as is quite violent about it! A couple of people have told me about a washer that can break up and also a collar of sorts that gets worn and allows it to ride out of gear. Think i may remove top cover and pto box to aid removal, will have another session on it at weekend Quote Link to comment Share on other sites More sharing options...
deadline Posted June 13, 2012 Share Posted June 13, 2012 TM9-801 page page 153 para 63c c. Slips Out of Gear. This condition is usually caused by weak or broken shift rod poppet springs, a bent shifting fork, or the gears in the transmission are worn excessively and the transmission assembly must be replaced (pars. 154 and 155) I assume by washer they mean a thrust washer? No matter what, you are taking out the entire unit. For a free copy of TM9-801 go to: http://www.tm9-801.com/tm9-801/index.php Quote Link to comment Share on other sites More sharing options...
T.Watts Posted June 16, 2012 Author Share Posted June 16, 2012 Progress on the gearbox today, think I have found the problem as well! Removed the top cover to have a peek inside and from what I can see it looks like the selector dog for 4/5th gear is very worn and so are the teeth inside 4th and 5th which the sliding dog drives. some of the other gears also look worn but will look at it harder when the box is right out. Also removed the pto box in the end to ease getting the gearbox out. Quote Link to comment Share on other sites More sharing options...
deadline Posted June 17, 2012 Share Posted June 17, 2012 (edited) My jeeps hi/lo selector fork was worn (common jeep transfer case issue) and I welded up the fork pad (GMAW - MIG), filed and fit the fork back in place. There was a few thousandths clearance when I was done. Hopefully that will last another 60 years. Those gears do not look to worn. A little chamfer on the leading edges is just bad double clutching. What you are really concerned about is the mesh of the teeth. You can dress the gear with a file to clean up the burrs. But most of the time the gears proper are not the cause of popping out... the forks/rails/poppets are. but if you have the £ to put in new gears, go for it... a how to would be great! Edited June 17, 2012 by deadline Quote Link to comment Share on other sites More sharing options...
Pete Ashby Posted June 17, 2012 Share Posted June 17, 2012 It would be worth checking thrust washers and bearings while the the box is out as end float either in the main shaft lay shaft or both can be a cause of gear jumping Pete Quote Link to comment Share on other sites More sharing options...
Vulture Posted June 18, 2012 Share Posted June 18, 2012 Tom Best of luck with this, I'm watching your adventures with great interest (as I'm sure many are). Please keep up us updated with lots of pictures. Kind regards Vulture Quote Link to comment Share on other sites More sharing options...
T.Watts Posted June 27, 2012 Author Share Posted June 27, 2012 Thanks for the advice people, dropped the gearbox out this evening with the forklift, a pallet and a block of wood in the end. Some of you may notice the forklift is getting close to the wing mirror, yes I did smash it and here is the critter that is causing the problems!! sorry if not very clear The gearbox isn't going to be rebuilt for now as want to use the truck in a couple of weeks so another gearbox has been acquired and is going to be fitted, all going well hopefully I will have 5th gear back! plus I have bought another truck and want to get on with restoring that Quote Link to comment Share on other sites More sharing options...
Vulture Posted June 28, 2012 Share Posted June 28, 2012 For the self confessed novices :n00b: like myself, which cog in the picture is causing the problem, and although your using a different box would it be easy to sort out if you wanted to ? Kind regards Vulture Quote Link to comment Share on other sites More sharing options...
T.Watts Posted July 4, 2012 Author Share Posted July 4, 2012 Hi Vulture The picture is a little blurry but the teeth around the inside of the gear have gotten rather rounded, plus had a proper look at the old box and found that 5th gear has some play in it allowing it to come out of mesh with the selector/synchro. I don't really know how difficult it would have been to repair, but would have had a go had a blitz on the truck tonight and the gearbox is now ready bar putting on the top cover and bolting in the floor, realised that I want to use the truck Saturday afternoon!!! Quote Link to comment Share on other sites More sharing options...
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