mazfg Posted March 19, 2017 Share Posted March 19, 2017 I've spent the weekend refitting my gearbox...which was a struggle but it's all in and I ran it without the propshaft attached. All is good apart from I've noticed the rear oil seal seem to be leaking a tiny bit . The guy who refurbed forgot to do this and prior to refitting I tried to get the castellated nut off to remove the flange..but no go and with the MOT next Fridqay (and bad whether in the week) it was do or die this weekend. Now I did think about doing in situ. My only problem is the gearbox tunnel won't allow me to get a socket in..less access as I also have OverDrive. I though I may grind some of it off to allow this.The nut seems to be on pretty tight...is it ok to lock eveythingby putting it in gear and then undoing? I had no hope before when it was on the bench as It wouldn't lock with my mole grips...Any advice appreciated. Quote Link to comment Share on other sites More sharing options...
iggy Posted March 19, 2017 Share Posted March 19, 2017 from what ive read you need to make flange bar, a suitable length of tube or angle iron with 2 bolts welded on the end to fit the flange once this is fitted it will jam on the concrete under your car when the flange is turned,to get better access can you not undo the rear gearbox mounts and lower the rear end of the gearbox on a trolly jack, to udo the nut you will need an impact wrench or a long half inch drive bar for the socket Quote Link to comment Share on other sites More sharing options...
glang Posted March 19, 2017 Share Posted March 19, 2017 What iggy says is the right way to do it but as a quicker bodge it can be done by putting bolts through two of the flange hole, doing them up tight and then wedging a correct size spanner on one nut against the other. Then spanner can then be locked against the floor of the vehicle to allow the nut to be undone be warned though that the recommended torque does say 90 - 100 lb.ft..... Quote Link to comment Share on other sites More sharing options...
mazfg Posted March 19, 2017 Author Share Posted March 19, 2017 I just got some info about using a screwdriver to lock the gears by selecting 2 at the same time.:Take the selector mechanism off the top of the gearbox and look in you will see where the selectors slot into the gearbox. Move one in one direction and the other one in the opposite direction so two gears are selected. This will prevent the flange from turning. Once you have finished changing the seal and replaced the flange and tightened up the nut move those parts back before you replace the selector mechanism. Quote Link to comment Share on other sites More sharing options...
glang Posted March 20, 2017 Share Posted March 20, 2017 although Im not averse to a bit of bodging I would try to avoid putting the torque of undoing/doing up the nut through the gear train. One thing is that the nut will probably become 'spongy' to torque as you take up the slack so making it difficult to get positive force on it.....If its already filled dont forget the oil in the gearbox when you take out the seal Quote Link to comment Share on other sites More sharing options...
mazfg Posted March 20, 2017 Author Share Posted March 20, 2017 I think I prefer the steel bar method attached to the flange. Not sure why it needs nuts welding to it. Surely a couple of holes and and then bolted to the flange will work and then jammed on against the floor Quote Link to comment Share on other sites More sharing options...
Jonny-Jimbo Posted March 20, 2017 Share Posted March 20, 2017 Could it work in the same way as undoing the crank front bolt and turning over the engine on the starter to knock it loose? So tool on the flange and another one on the nut? Quote Link to comment Share on other sites More sharing options...
Pete Lewis Posted March 20, 2017 Share Posted March 20, 2017 There are interlock pins and balls that prevent selecting two gears at once situated between the 3 shaftsthe tunnel should be cut back a good few inches to allow access to overdrive coouplings has a simple screw down tin plate made to cover the prop tunnel gap a pair of bolts thru the coupling and lock it with a pry bar should be easy to hold the coupljng from rotating its not gorilla tight pete Quote Link to comment Share on other sites More sharing options...
mazfg Posted March 20, 2017 Author Share Posted March 20, 2017 If I remove the OD mount bottom screwas....could I jack it up enough to pass the prop tunnel..thereby giving me access without cutting more metal out? Quote Link to comment Share on other sites More sharing options...
Pete Lewis Posted March 21, 2017 Share Posted March 21, 2017 if sure that will get it close, watch out for hose stretch etc. tip if you remove the mount to the base plate , tack weld the bolts into the mount as spanner access to hold the hex is more than a challenge, if tacked you can fit the nuts underside .........,one handedPete Quote Link to comment Share on other sites More sharing options...
mazfg Posted March 21, 2017 Author Share Posted March 21, 2017 Quoted from Pete Lewis tip if you remove the mount to the base plate , tack weld the bolts into the mount as spanner access to hold the hex is more than a challenge, if tacked you can fit the nuts underside .........,one handedPete I found that out at the weekend..much toing and froing.. Will the output flange come out easily or will I need a hub puller on hand? Or easily tapped out? Quote Link to comment Share on other sites More sharing options...
Pete Lewis Posted March 22, 2017 Share Posted March 22, 2017 Od couplings normally just pulls off or may be a tap with a malletits not a gorilla fitpete Quote Link to comment Share on other sites More sharing options...
mazfg Posted March 28, 2017 Author Share Posted March 28, 2017 Ive made a bar up fitted to the flange. .unfortunately every time I try to undo the nut, the gearbox rises up when the bar is hard against the floor. .ahh. Seems like I need to find away of keeping the gearbox down. Problem is..it's already raised up to get the socket in for the castellated nut. ... Quote Link to comment Share on other sites More sharing options...
Dogsbody47uk Posted March 28, 2017 Share Posted March 28, 2017 Quoted from mazfg Ive made a bar up fitted to the flange. .unfortunately every time I try to undo the nut, the gearbox rises up when the bar is hard against the floor. .ahh. Seems like I need to find away of keeping the gearbox down. Problem is..it's already raised up to get the socket in for the castellated nut. ... Can you reposition your bar so that it lodges against the chassis rather than the floor? Quote Link to comment Share on other sites More sharing options...
mazfg Posted March 28, 2017 Author Share Posted March 28, 2017 Quoted from Dogsbody47uk Can you reposition your bar so that it lodges against the chassis rather than the floor? I think it will still rise up even if against the chassis rail as as soon as it hits anything it'll lever up the gearbox. Quote Link to comment Share on other sites More sharing options...
Dogsbody47uk Posted March 29, 2017 Share Posted March 29, 2017 If you can position your lever against the underside of the chassis right hand main rail, then as you try to undo the nut it will force the gearbox downwards against whatever you are using to prop the gearbox up. ( right hand looking from front to rear ). That should do it. Cheers, Dave. Quote Link to comment Share on other sites More sharing options...
Pete Lewis Posted March 29, 2017 Share Posted March 29, 2017 I have a 1/2" Mac 19.5 volt 330 lbft impact gun which shifts just about anything triumphI have 3 makita drills but dont know about their impact wrench ,, not to be confused with a impact driver which is normally aimed at screws not 32mm nutspete Quote Link to comment Share on other sites More sharing options...
mazfg Posted March 29, 2017 Author Share Posted March 29, 2017 Quoted from Pete Lewis I have a 1/2" Mac 19.5 volt 330 lbft impact gun which shifts just about anything triumphI have 3 makita drills but dont know about their impact wrench ,, not to be confused with a impact driver which is normally aimed at screws not 32mm nutspete Mmmm..yep..I mean impact driver. ..I've a hex to 1/2" adapter on it...I'll give it a go anyway. .but mIghtfield not be man enough. I've just made up a new triangulated bar to use....going to try it all tomorrow morning. Quote Link to comment Share on other sites More sharing options...
mazfg Posted March 30, 2017 Author Share Posted March 30, 2017 Well, here's the tool I made. It made very light work of it in the end. Popped the old seal out really easily too. New one went in square and used a piece of pipe to carefully knock it in. Took it out for a spin..to check...came back and the bloody thing is slightly weeping oil out.... I'd cleaned up the flange ok..could see where the old seal was sitting on the flange and it looked smooth without nicks in it....not sure what's gone wrong..it's a fairly simple procedure.. Quote Link to comment Share on other sites More sharing options...
RobPearce Posted March 30, 2017 Share Posted March 30, 2017 I had a similar experience with Toby, many years back, when he belonged to my brother. The O/D rear seal was leaking so we replaced it... and it still leaked. Some months later, my brother declared that it no longer leaked but given his mechanical skills I suspect that was because it ran out of oil (the O/D had never worked so the obvious symptom wouldn't apply). When I rebuilt the whole shebang some years later to go in Felix (the other brother's Mk2 Spit) I managed to get a good seal. Quote Link to comment Share on other sites More sharing options...
mazfg Posted March 30, 2017 Author Share Posted March 30, 2017 I'm hoping it may settle down..bed in... When the oil is hot and thinner that's when it weeps. The seals seem to be a standard universal part 513231. I did have a simialr thing when I did my crank front seal that sits in the timing chain cover. Went through about 5 and it still leaked..until I bought a full metal jacket type one from Barnwell. been good ever since.I shall monitor and potentially buy another and try again..bit of a pain but I now know it's only an hour or so job Quote Link to comment Share on other sites More sharing options...
Pete Lewis Posted March 30, 2017 Share Posted March 30, 2017 glad its off...on off think weve all been there from time to timei would burnish the coupling with some 1200 grit it may show a wear line, skf and others make wear sleeves , this is a very tin tap on tube to repair worn journals and uses same seal .on production in the 80s we fitted them a std to all our axles so its not a bodge .so repairs could be done in later life. do check the OD breather and the small hole in the gearbox top cover ( under the selector rod casting are open and working)Pete Quote Link to comment Share on other sites More sharing options...
mazfg Posted March 30, 2017 Author Share Posted March 30, 2017 Quoted from Pete Lewis do check the OD breather and the small hole in the gearbox top cover ( under the selector rod casting are open and working)Pete I'll have a look, it's that black thing on top of the OD. Wish I'd burnished it now before putting it all back...too keen. It looked perfectly smooth, with a mirror like finish. I did wonder though if the new seal lip was in a different place to the old and may sit further out..in which case it was more cruddy further out? Quote Link to comment Share on other sites More sharing options...
nang Posted March 31, 2017 Share Posted March 31, 2017 I'd try to find a double lipped seal. Also fit a speedi sleeve as already mentioned.Tony. Quote Link to comment Share on other sites More sharing options...
mazfg Posted March 31, 2017 Author Share Posted March 31, 2017 I've just taken it out for another spin and it seems to be good now. Any recommendations on where to buy sleeves? Quote Link to comment Share on other sites More sharing options...
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