Gearbox Refurb
Discussion
Thanks, is this the sort of bearing puller i will require? http://www.ebay.co.uk/itm/Upgraded-14pcs-Gear-Bear...
Or is it something a bit more sophisticated than this required?
Or is it something a bit more sophisticated than this required?
A tool like that will prob do it. Yo umay need a 3 leg puller, you won't know until you get in.
Re bearings, we all know Honda don't make their own. They buy in Timken, SKF, GKN, whoever. Any bearing has a unique ID number, go to any bearing supplier in a big city and ask for a SKF 123-ABC and they'll have a replacement available. Bearings don't care whether they are in a Honda gearbox or a JCB hydraulic pump, after all, as long as they are lubricated and used within the spec. Mr Honda Engineer knew his stuff when he specified what he did, so replace it like-for-like and you'll get the same service.
Re bearings, we all know Honda don't make their own. They buy in Timken, SKF, GKN, whoever. Any bearing has a unique ID number, go to any bearing supplier in a big city and ask for a SKF 123-ABC and they'll have a replacement available. Bearings don't care whether they are in a Honda gearbox or a JCB hydraulic pump, after all, as long as they are lubricated and used within the spec. Mr Honda Engineer knew his stuff when he specified what he did, so replace it like-for-like and you'll get the same service.
Argh! Starting to regret this now!
Out of the 6 bolts that hold the prop shaft to the box, 4 are completely rounded!
Obviously this has been off before.
On the plus side after drenching in pen fluid, the 2 that are not rounded came out relatively easy.
But not sure how I'm going to get the other 4 out
They are 6mm Allen bolts, and there is only around 2mm clearance, so can't get a socket over the top etc.
Tried turning it with stillsons but they just slip off!
Anyone got any good tips to get these buggers out?
Out of the 6 bolts that hold the prop shaft to the box, 4 are completely rounded!
Obviously this has been off before.
On the plus side after drenching in pen fluid, the 2 that are not rounded came out relatively easy.
But not sure how I'm going to get the other 4 out
They are 6mm Allen bolts, and there is only around 2mm clearance, so can't get a socket over the top etc.
Tried turning it with stillsons but they just slip off!
Anyone got any good tips to get these buggers out?
R1 Indy said:
Argh! Starting to regret this now!
Out of the 6 bolts that hold the prop shaft to the box, 4 are completely rounded!
Obviously this has been off before.
On the plus side after drenching in pen fluid, the 2 that are not rounded came out relatively easy.
But not sure how I'm going to get the other 4 out
They are 6mm Allen bolts, and there is only around 2mm clearance, so can't get a socket over the top etc.
Tried turning it with stillsons but they just slip off!
Anyone got any good tips to get these buggers out?
Either weld a bar onto each one in turn (I've never tried that) or use Mr Angle Grinder Out of the 6 bolts that hold the prop shaft to the box, 4 are completely rounded!
Obviously this has been off before.
On the plus side after drenching in pen fluid, the 2 that are not rounded came out relatively easy.
But not sure how I'm going to get the other 4 out
They are 6mm Allen bolts, and there is only around 2mm clearance, so can't get a socket over the top etc.
Tried turning it with stillsons but they just slip off!
Anyone got any good tips to get these buggers out?
I have tried that and as long as you can get new bolts you're OK.It's slow and laborious, but it works. A hammer and chisel at an angle will start to turn them, tap it round until you can get in with pliers etc. Or Dremel a slot in the head and get a screwdriver in. If not, then it's grinder time. No, I don't mean a gay dating site, but then again that might cheer you up if all else fails and you still have a car that won't go and won't come apart either.
A good tip for getting rounded off cap head bolts out is to tap a torx head socket into the bolt it needs to be a big bigger than the 6mm hex. Then put your wrech or breaker bar on and hopefully it will come out. The six teeth bite into hex. Looking at some sizes charts a T40 should be ideal.
R1 Indy said:
This is the parts diagram, looks like 3 main bearings. 
You do know that is only the tail shaft of the gearbox, not the bit where the actual changing of gears goes on, don't you.Edited by R1 Indy on Thursday 4th February 20:00
Edited by R1 Indy on Thursday 4th February 20:05
bern said:
A good tip for getting rounded off cap head bolts out is to tap a torx head socket into the bolt it needs to be a big bigger than the 6mm hex. Then put your wrech or breaker bar on and hopefully it will come out. The six teeth bite into hex. Looking at some sizes charts a T40 should be ideal.
That.If not, grind/dremel the heads off; once the porpshaft flange is out of the way you'll have 6mm stubs (now not under tension) to heat and a clear run with the molegrips to un-wind from the 'box output flange at leisure Much, much easier, and you'd be replacing the knack'd cap screws anyway.
OP, if you get really stuck, speak to Phil Stewart at Road & Race Transmissions near Sevenoaks in Kent. They have a superb reputation in the Caterham 7 community but do all makes of gearbox. I have personally used them to refresh my Caterham's 6 speed box, they pulled it apart, replaced 2 synchos and all the bearings and the cost was £360. I dropped the box off myself so saw first hand the work they do and I can't speak highly enough about them. I know it's a long way from you but they are quite happy to organise postage so you don't have to go there yourself.
grenpayne said:
OP, if you get really stuck, speak to Phil Stewart at Road & Race Transmissions near Sevenoaks in Kent. They have a superb reputation in the Caterham 7 community but do all makes of gearbox. I have personally used them to refresh my Caterham's 6 speed box, they pulled it apart, replaced 2 synchos and all the bearings and the cost was £360. I dropped the box off myself so saw first hand the work they do and I can't speak highly enough about them. I know it's a long way from you but they are quite happy to organise postage so you don't have to go there yourself.
This. These guys have a great reputation. Alternatively take the car to TGM in Fleet. A great Honda specialist who looked after my DC2 for years.Thanks guys, I've managed to now get the prop off.
I ended up drilling a 6mm hole through the side of the bolt head, inserting a long screwdriver, and after a couple of snapped screwdrivers they came out
However I'm now in another world of pain....
I needed to lower the subframe a few inches in order to get to the top tranny bolts.
Only on one of the bolts, it appears the welded nut inside the chassis seems to have come loose!
So when I either tighten or loose the bolt, the nut just spins inside
Looks like I may have to make a hole in the chassis to access this bolt?
I ended up drilling a 6mm hole through the side of the bolt head, inserting a long screwdriver, and after a couple of snapped screwdrivers they came out
However I'm now in another world of pain....
I needed to lower the subframe a few inches in order to get to the top tranny bolts.
Only on one of the bolts, it appears the welded nut inside the chassis seems to have come loose!
So when I either tighten or loose the bolt, the nut just spins inside
Looks like I may have to make a hole in the chassis to access this bolt?
You need to source the workshop manual applicable to your gearbox before attempting to dismantle it.
An exploded parts list is not a substitute.
You cannot possibly do the job without it.
You should then read it throughly before starting the job and familiarise yourself with the process. You will need bearings and shims and replacement lock nuts for the shafts you replace the bearings on. If you're going to strip the box I would refurbish the synchro hubs at the same time.
You need to check on availability and price of parts. Sometimes folks in the trade can source parts that are not available to the retail customer!
Remove any suspect bearing's from their shafts and clean using a suitable degreasing fluid in a plastic bowl.
Don't spin bearings using compressed air. Make sure everything is clean before reassembly.
The bearings should feel smooth and tight without lots of play between the inner and outer races, not gritty when you spin the outer race with your fingers and no whine!
If one of the shafts is damaged, bar possibly the output shaft in your parts list, a secondhand box is possibly the better bet.
An exploded parts list is not a substitute.
You cannot possibly do the job without it.
You should then read it throughly before starting the job and familiarise yourself with the process. You will need bearings and shims and replacement lock nuts for the shafts you replace the bearings on. If you're going to strip the box I would refurbish the synchro hubs at the same time.
You need to check on availability and price of parts. Sometimes folks in the trade can source parts that are not available to the retail customer!
Remove any suspect bearing's from their shafts and clean using a suitable degreasing fluid in a plastic bowl.
Don't spin bearings using compressed air. Make sure everything is clean before reassembly.
The bearings should feel smooth and tight without lots of play between the inner and outer races, not gritty when you spin the outer race with your fingers and no whine!
If one of the shafts is damaged, bar possibly the output shaft in your parts list, a secondhand box is possibly the better bet.
Well the box is finally out!!
Ive cracked the rear open, the top bearing does not look too bad? It looks like to completely remove the rear, i need to get the main shaft bolt off which will be difficult as the shaft will just spin!
Im pretty sure its been opened before, as the instant gasket is a bit messy, also is it me or does the rear look like its been repaired?
Im in 2 minds now weather to get it fixed or just get another box? As i will need a new rear mount (was damaged) and cant find one. Plus if this box has been repaired before??
Ive cracked the rear open, the top bearing does not look too bad? It looks like to completely remove the rear, i need to get the main shaft bolt off which will be difficult as the shaft will just spin!
Im pretty sure its been opened before, as the instant gasket is a bit messy, also is it me or does the rear look like its been repaired?
Im in 2 minds now weather to get it fixed or just get another box? As i will need a new rear mount (was damaged) and cant find one. Plus if this box has been repaired before??
Thanks, the more i look at it, the more it looks like its been welded and grinded back.
Im pretty sure this would not be how it will have come from Honda?
But i cant get my head around how it would have been damaged up there?
I wonder if this is why my gear selections have always been a bit rough?
If this is the case i think i will go for another box.
Im pretty sure this would not be how it will have come from Honda?
But i cant get my head around how it would have been damaged up there?
I wonder if this is why my gear selections have always been a bit rough?
If this is the case i think i will go for another box.
Yeah, looks like a weld repair to me. Mine is very smooth there (sorry not a great pic)
Having dismantled a gearbox once which I didn't need to put back together, I wouldn't even consider trying to recondition one myself, I reckon you'll spend as much in specialist tools as it'd cost to get it done. Maybe I'm just soft though
ETA though I doubt that misalignment on the repaired bit would matter too much - it's only the end of the control rod which has to move around anyway, so I doubt if a few mm here and there would make a lot of difference.
Having dismantled a gearbox once which I didn't need to put back together, I wouldn't even consider trying to recondition one myself, I reckon you'll spend as much in specialist tools as it'd cost to get it done. Maybe I'm just soft though
ETA though I doubt that misalignment on the repaired bit would matter too much - it's only the end of the control rod which has to move around anyway, so I doubt if a few mm here and there would make a lot of difference.
Edited by CrutyRammers on Saturday 27th February 14:00
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