BW65 - No reverse gear (or top!)

M

Madalicesdad

New Member
Since I rebuilt and refitted my BW65 box and tuned the V8 in January, it's been running beautifully. Bags of torque, kickdown working, smooth changes.
But today...

On the way to work this morning I noticed it was reluctant to change into top unless the throttle was fully released. Then it wouldn't change into top at all. Then it changed from 1-2 very early but had no acceleration in 2. When I got home, no reverse either. And all this in the space of 15 miles.

I've added ATF just to make sure it's not that, but no difference at all (I'll do a proper check when it's cold).

Any help/suggestions very very welcome.

Mike
:(
 
Finally got around to removing the box. I suspected the rear clutch (I had failed to get it apart for inspection when I threw the box back together last time) and was not wrong.
Having separated the front and rear clutches with a bolster chisel and lump hammer, it was obvious where the fault was. The rear clutch piston seal had failed, stopping the rear clutch from disengaging and burning it out. The chisel was needed because the plates had distorted and clamped the clutches together.

However cannibalising the two boxes i had gave me everything I needed apart from new friction plates. All local gearbox specialists refused to supply individual parts and refused to tel me who they got bits from. However I trawled t'internet and found JPAT (www.jpat.co.uk).

If you are after BW gearbox bits, the JPAT website has a full breakdown of parts for all BW boxes (and many other makes). They can supply just about any bits you need and the cost is very reasonable. Friction plates were £1.98 each and the gasket set was less than £15 (last time I bought a gasket set alone from a classic car parts supplier it cost £25). Although I called in to collect the bits I needed (they are near Bristol airport), they do mail order as well. If you need any bits I would highly recommend getting in touch with them (website/email or tel 01934 852772)

Note that I have no connection with them other than being a very satisfied customer.

I've since rebuilt and fitted the box and 30 miles on, all seems well!


Mike
 
I'd be very interested to know how you managed to re-fit the piston and seal back into the rear clutch drum
 
Probably with a hammer and chisel! :p if it works!! use it!!
you dont always need that specialist tool when you can use one of your own design that works :D
I wonder how many weird and wonderful "tools" all we amateur improvising!! home mechanics have come up with, to save trying to, find,borrow,even buy!! the proper item. :laugh:
 
Thanks for the tip off on where to buy auto gearbox parts :D

I've got to have a go at rebuilding Erik's BW65 at some point. I've never played with an auto box before, so if you see an atomic mushroom cloud over Derbyshire.............That'll be me, losing my temper with it!! :laugh:
 
A hammer? Please give me some credit! I lubed the seal with ATF and used two G clamps to slowly press the piston into place. The hammer was on standby though.

As for homemade tools, I had to make one to release the rear clutch piston assembly in the first place. I used a 10" piece of M10 threaded bar and a 2" length of 2" dia tube with a cutout to access the circlip, a few washers and nuts. Probably not as efficient as the proper Rover tool, but did the job and cost nothing. (If anyone wants a photo of the tool I made so they can fashion their own, let me know).

Regarding stripping/rebuilding auto boxes, just be patient and use a detailed manual (I used the BL workshop manual). Photocopy the pages and as you complete each step, bag each part, number it against the step in the book and cross it off on the photocopy. That way you know you've done everything, and also know which bits go where when it comes to reassembly.

Access to a compressed air line is essential for clearing blockages and removing pistons. Tip - cover the box with a towel when pressurising any fluid pipe as it sprays everywhere.

Oh, and never underestimate how much ATF will p155 out of the box even when drained. :)

Good luck.

Mike
 
mike,
I am loosing rev on mine,I am going to fit the 35 back in pro tem when it goes completely,or b4 if i get a chance to, while I,um!!!!err!!! we!! fix the 65. I think its maybe just the rear band. will pop in for a natter when I can.
QAS in bristol did a questionable rebuild on it!!£450!! and only done 9k!! but nearly 4 yrs ago.
dave
 
The only used box I would even consider is one that's still in the car and can be test driven. Once they get removed there's no telling how good they are, and sitting with no oil in them just makes the seals deteriorate.Absolute maximum from my viewpoint would be £50
 
hi beaser,
the 35 is rod driven and the 65 is cable driven. YES it can be swapped straight over, the only thing you will need to do is fasten a bracket to the top of the transmission tunnel between where the gear lever comes up and the handbrake lever to hold the cable ( cable is threaded for adjustment ) and a couple of pop rivets on the drivers side to hold the cable from rubbing on the propshaft.

ian
 
Hi ian,??.??
Ive got to pop a 35 in while I remove and fix the 65,i've got the oil pipes.
The only problem I forsee is the gear change linkage. ???
How do I temorarilly adapt the 65's cable to the rods on the 35? ??? :D
dave
 
Changing the 65 cable linkage to the 35 rod linkage when you change the box is dead easy, as the rod linkage all mounts on the bellhousing. If you haven't got the rod type linkage to go with the box, go out and get one, as I that will be easier than making the 35 box cable operated.
 
thanks harvey,
I have both rods and the transfer link on the box, but is the bottom link of the gearlever any different ???,
I cant remember :( ,and I cannot find the gearlever assembly I originally had on it,that is, if I did change it back then? or did I leave it on coz it was ok? ??? doh!!!!!!
 
harvey,
Ive just looked in the book,and ive got the tie rod missing! that will explain the broken bit off the "compensator" or plastic transfer hinged link bolted onto the box.
Looking at the diagram, ITS Real over engineering!! I presume that it is to take up any movement from the eng/box to keep the link adjustments ok,
Can I presume it will work without it ??? as its a bit stiff on its mount so it wont move under selecting gear in car, but might be a little difficult to engage gears sometimes,if it moves a bit
I only do low mileage cruising and not normally fast unless on the M way. It should get me by for a good week or 3 at least, till I fix the 65 :p
dave
 
You must log in or register to reply here.
Back
Top