rcreweread Posted June 10, 2016 Report Share Posted June 10, 2016 Am really struggling trying to fit my newly rebuilt ( & TR converted ) Stag gearbox and J type overdrive - I have simply removed my old A type unit, leaving the clutch in situ - it's a 4A diaphram clutch - so there should be no alignment issues re the clutch. I have replaced the old A type gearbox crossmember with one of the proprietary modified ones, but the problems are that I just cannot get the gearbox to mate up I have jacked the back of the engine up as far as it will realistically go, have removed the propshaft to create more room, and selected a gear so we can rotate the main shaft, but then I'm stuck I can't even manoeuvre the clutch arm to below the floor because I cant get the gearbox far enough forward for the arm to go into the indent in the floor plan to allow for this - I cant revolve the gearbox clockwise to allow the arm to clear the floor because the underneath of the J type OD ( it's like a rectangular block) is fouling on the crossmember and thus preventing the whole unit from revolving in this direction. It also appears to stop the back end of the unit being low enough to line up with the overall angle of the engine/flywheel/clutch - it seems to me the only way round this is to remove the crossmember totally, try not to drop the whole lot into my pit, and then fit the crossmember if the unit mates together - it looks like this should be possible but very tight , Is this how it's supposed to be done? Getting very frustrated! FWIW, there is a previous post from me describing the problems I was having with the original set up whereby the crossmember was fouling the underneath of the overdrive unit and gouging into it - well it certainly did that and once removed and cleaned up, it was apparent that it had just cut through the casing, but it is repairable. The reason appears to be that it was the wrong crossmember ( possibly the botom plate of a TR3 set up), not aided by the fact that rubber gearbox mounting had split totally in half - although 3/4 years old, I had done less than 2000 miles on it. Another **** part! Anyway, if anyone has any advice/tips, I would be very grateful PS How important is the fibre washer between the gearbox and speedo angledrive (I don't have one to hand!), and can I make do with one home made from a piece of inner tube ie rubber or is this likely to disintegrate in no time at all and cause a whole host of other problems Quote Link to post Share on other sites
ctc77965o Posted June 11, 2016 Report Share Posted June 11, 2016 Is it an input shaft problem ( splines not going together ) or a crosmember mechanical fit problem? Quote Link to post Share on other sites
rcreweread Posted June 11, 2016 Author Report Share Posted June 11, 2016 Dave I'm fairly sure it's not a spline issue as I've tried an old clutch plate on both the new gearbox and the old one and it fits fine - although I haven't disturbed the clutch, my alignment tool slides in fine as well. The new crossmember installs fine on it's own, it just seems to get in the way of twisting the gearbox to get the cross shaft clutch arm to clear the floor. As I said in my original post, it looks like I will need to remove the crossmember to allow sufficient access to align the gearbox and engine so the splines engage properly - this means the gearbox is taking up a position with the gearlever pointing at 2 to 3 oclock, as it were. Then the gearbox can move forward and allow clearance for the cross shaft arm when you then twist the whole gearbox anticlockwise to allow it to rotate into the gap in the floorpan - it's difficult to describe easily but hopefully you can understand what I mean. I'm presuming this is the way forward, and hopefully I can then fit the crossmember afterwards - I'm fortunate to have a pit underneath the car, but I don't have a transmission jack so it makes supporting the gearbox whilst maintaining access difficult, but hopefully with advice from all the learned cognoscenti on here, I will learn the answer! Cheers Rich Quote Link to post Share on other sites
graeme Posted June 11, 2016 Report Share Posted June 11, 2016 (edited) Has the input shaft been changed as the Stag input shaft is longer than a TR one. Another possibility, if I remember correctly you had a saloon A type fitted? The saloon has a 1" input so possibly you have a clutch to suit 1" and not the 1.25" required for a TR input. OK , you posted while I was typing. I have a J type in my TR4A and I usually fit it with cross member out. Re-install the cross member after the box is in position. Cheers Graeme Edited June 11, 2016 by graeme Quote Link to post Share on other sites
rcreweread Posted June 11, 2016 Author Report Share Posted June 11, 2016 Graeme The stag input shaft has been changed for a TR one and it was a TR A type which I removed, so all the relevant inputs are 1.25" - the saloon unit you are thinking of is for a different project! Cheers Rich Quote Link to post Share on other sites
TR NIALL Posted June 11, 2016 Report Share Posted June 11, 2016 Take the Crossmember out and drop the angle of the Engine if Working from below. Put a few lengths of Timber on top of each other and across the Pit to support the Box,you'll be able to manoeuvre them to suit your needs,have Fun. Quote Link to post Share on other sites
Stevecross Posted June 11, 2016 Report Share Posted June 11, 2016 Rich If you lay a short length of steel bar across the floors an inch or two ahead of the propshaft (or where it would be if fitted) you have something to support the rear of the box while you are huffing & puffing. Alternatively, see you Sunday! Steve Quote Link to post Share on other sites
TR NIALL Posted June 11, 2016 Report Share Posted June 11, 2016 Second Thoughts,I done as Steve above,a Length of 1/2inch Pipe at the back of the Box between the Flange(the lowest part) and reduce the angle of the Engine. Quote Link to post Share on other sites
rcreweread Posted June 11, 2016 Author Report Share Posted June 11, 2016 Thanks guys - I'll follow your suggestions - out with the crossmember! I have plenty of thick timber planks which normally cover the pit but they are quite wide and hence hinder access when used, so I'll try and find a shortish scaffold pole or similar. Fingers crossed, Steve, so you can have an uninterrupted sunday! cheers Rich Quote Link to post Share on other sites
Stevecross Posted June 11, 2016 Report Share Posted June 11, 2016 Rich You will probably find a couple of long 1/2" socket extension bars are enough. Steve Quote Link to post Share on other sites
BlueTR3A-5EKT Posted June 11, 2016 Report Share Posted June 11, 2016 1. Cross member out. 2. Get an assistant. Brother and I made a 'skateboard with scissor jack and cradle' assy. to support the gearbox/o.d unit in 1973 to do his TR3 gearbox. Subsequently we found having me under the car lifting while he guided and arranged from above, plus a bar across the floors to support the tail made life simple. I have improved on that and have fitted a couple of very long studs to align the gearbox before the clutch shaft engages. You can see what's happening then, and do not risk snagging the gearbox input shaft on the clutch diaphragm fingers. Peter W Quote Link to post Share on other sites
rcreweread Posted June 11, 2016 Author Report Share Posted June 11, 2016 Well it's in! For future info, as suggested, I took the crossmember out and supported the back of the unit with a long socket extension bar - however the back was still too high and I couldn't raise the back of the engine any more, so had to remove the bar and lower the back end even more - with help from my son above and me underneath, we managed to get the splines engaged a little way, then with more jiggling about managed to get it almost home. Fitting the adapter crossmember was ok, but I had previously dry fitted it and had to modify the mounting holes to match my chassis mountings, not a lot, but enough! It then became obvious that the elongated central mounting hole in the bracket needed to be extended even further backwards ( fortunately the bracket has plenty of meat to do this without a problem) and the cut out in the side of the bracket for the solenoid needed to be enlarged and extended as clearance was minimal even with 3 washer spacers under the central rubber mounting - can't really use any more as there wouldn't be enough stud showing underneath to fix a nut to properly. So removed the crossmember, modified it and then painted it - will reinstall tomorrow and connect up everything else ( mustn't forget my GB40!) and hope for the best. Have to say a little surprised that the mounting needed to be modified as much as it did - I can't be sure but I think it was a Moss item - it looks exactly like the one in their catalogue. Will update tomorrow cheers Rich Quote Link to post Share on other sites
peejay4A Posted June 11, 2016 Report Share Posted June 11, 2016 I seem to remember that there are two holes for the front engine mounts. Are yours in the rearmost ones I wonder? (Can't remember which is correct). Quote Link to post Share on other sites
stuart Posted June 12, 2016 Report Share Posted June 12, 2016 If its an older bracket then they were notorious for needing a fair bit of "fettling" to get them to fit. Stuart. Quote Link to post Share on other sites
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