Borg Warner Model 35

nigefoxx · Post by **nigefoxx** » Thu Dec 14, 2006 9:44 pm

Hey all

First off, got my bearings back after the forum swap..

Just fitted up to the tired old 3.5 a new(ish) carb to replace the wonky/blocked/worn SU's, and now I've got sufficient grunt under my right foot I've noticed that the box, under kickdown changes 1-2 at about 20mph (circa 3000 rpm, my gauge is a Vauxhall one which wobbles everywhere undamped) and from 2-3 at about 3500 rpm, at about 40 mph.

Reading up in the Haynes pamphlet for the BW65 out of the SD1- it says the gears should change at significantly higher speed than they do right now.. is that a difference of the two gearboxes, or alternatively is there any way beyond a complete rebuild of the thing to alter the speed at which it changes?

I don't have a pressure gauge to check what the pump pressure is, but it changes nice and smooth and positive, no slurring- the kickdown is adjusted just fine, the band tension is correct as much as I can get it.. I don't know enough about the 'box to figure what to do

toughy V8 · Post by **toughy V8** » Fri Dec 15, 2006 11:55 am

i had a problem where it wouldnt change unless i caned it and that turned out to be the regulator jammed at full pressure, so maybe you dont have enough pressure to hold the gears.

Post by **katanaman** » Fri Dec 15, 2006 12:29 pm

is this on normal change or kick down change?

nigefoxx · Post by **nigefoxx** » Fri Dec 15, 2006 6:39 pm

Kickdown it changes (in my opinion) too early.

Under gentle light throttle it's in top gear by about 15 mph, medium throttle about 15 mph, heavy throttle top by about 35 mph and kickdown top is about 40-50.

Note that this vid is with the SU's... hence the epic sluggish acceleration.

ozrover · Post by **ozrover** » Sat Dec 16, 2006 12:45 am

Sounds like the kickdown cable is a little loose in adjustment,you should have just a tiny bit of slack in it before it starts moving the valve in the valve body.
Doug

nigefoxx · Post by **nigefoxx** » Sun Dec 17, 2006 10:55 am

That was my immediate thought. I gave it a little more wind-out (on stock Rover/SU kickdown bracket linkage, so the travel is correct) to no avail. It had a fair bit of travel in the "kickdown" area- where you feel the kickdown cable tension up a little as it closes off the valve for kickdown. Still a little stumped.