BW 35

[fortnum1977]

Hello,

My auto box is going wrong on P5B coupe '72.

It's started making a shuddering noise almost like you're spinning the wheels and then engaging.

Sometimes it takes ages to engage... just seems to spin up.

Also it sounds like the noise is coming from the diff behind me sometimes.

All very worrying. There is a leak but the level is fine. I also noticed white streaks mixed in with the oil, which suggests a water leak.

So this is my first trouble with the bw 35 which has served me pretty well for 6 years.

I was wondering if anyone knows of a quick and cheap way out of this or am I looking at a new box? If so I'd like to put something in it with a taller gear, an overdrive for cruising, because the bw35 revs too high at high speed.

Thanks

[harvey]

Do you get these symptoms in both forward drive and reverse?

If you've got water in the box (most likely from a faulty cooler in the radiator) then eventually the fiction plates and bands will delaminate. (And tbh it doesn't take very long because the friction material is bonded on with a water based adhesive.....)

[fortnum1977]

reverse seems ok although it does take a moment to engage

[harvey]

Slow engagement is normally low fluid level, and that will affect forward and reverse drive equally, so if you've only got the juddering and occasional complete loss of movement in forward drive then I'd say that the seal on the front clutch piston has failed. To get at that the box needs to be removed and dismantled.

This may give you an idea of what is involved.

roverp5.proboards.com/thread/6931/bw35-strip-rebuild-pictures

[fortnum1977]

thanks so much

looks like a big job, I dont think i'll be doing it

a new box is really expensive i've noticed

[harvey]

Jun 14, 2013 14:01:10 GMT fortnum1977 said:

looks like a big job, I dont think i'll be doing it

^^^^^THAT^^^^^ is the reason for vvvvvTHATvvvvv

Jun 14, 2013 14:01:10 GMT fortnum1977 said:

a new box is really expensive i've noticed

The problem is that you have no way of telling the standard that it's been done to.

[johnwp5bcoupe]

Harvey is the man if you need a box rebuilding

[fortnum1977]

well i was so confused by the level reading that I threw caution to the wind and puts loads of the comma stuff in. It has improved hugely and now slips no more. The only thing that does remain is after you start it and drive a grawnching noise comes from the diff of rear end of prop shaft. But disappears after a short time.

I have a huge leak i think.

[harvey]

Aug 12, 2013 15:42:34 GMT fortnum1977 said:

well i was so confused by the level reading

check the fluid level as follows:

With the transmission at normal working temperature, the engine idling, and the car on level ground, run through the entire selector range allowing a few seconds in each position to allow it to engage, starting and finishing in PARK, then, with the engine still running walk round remove and wipe clean the dipstick and re-insert to take a level. You will have time for a few quick dips to try and get an accurate level. If you add fluid repeat the whole procedure before taking another level. Use only ATF-G or fluid that meets Ford spec. M2C-33G. DON'T use any of the DEXRON type fluids. A small amount of white blackboard chalk rubbed on the bottom of the dipstick, and then wiped off, dries it and makes seeing the level easier.