total loss of drive :(

[jonnyboy]

Hi all.
Got the ok to drive yesterday from my consultant. Great news after the best part of three months. Took advantage yesterday and today!
After some telephone help from a certain member (cheers Ian!) I sorted out the last few vacuum pipes on the SL. It all looked good tonight so when MRs JB went out for an hour I thought I'd put the air filter and what have you, and take the car for a blast up and down our street (private road).
Looking good, drove nice, smooth and very powerful. But,

On returning up the street, 5 or 6 doors away I totally lost drive. I mean completely. No bangs/whirrs/noises or anything. Just zilch. I checked the fluid which appeared to show the gearbox was overfilled (possible as it was an engine swap), fluid showed about 3inches above the max mark on the dipstick. imagine the furore, blagging some "car time" while the mrs is out, car stranded, her back in half an hour , and me on doctors orders to take it easy.

Eventually managed to get it on the (gravel grrr) drive using the Q7, a tow pole, a recalcitrant daughter, then eased it into the garage.

There was no warning and it was very sudden. It's an old-style 4 speed 'box.

Any thoughts?

 

[EDZ649]

Not sure about the car John but you had a lucky escape from the Mrs! Glad you're mobile again

 

[davidjpowell]

Something tells me that it is not plain sailing yet...

 

[trapperjohn]

Blimey John. Frying pan, fire. Whats your next trick. Nailing down four nuclear reactors in Japan!!

Take it easy.

 

[jonnyboy]

So the plot thickens.
Popped the bonnet and found loads of strands of copper wire mangled (no insulation to be seen) around the viscous fan assembly. I'm reasonably **** about ensuring everything is connected back up before I start a replaced engine, weird.
Now wondering if a cable could have come off the gearbox = loss of signal/drive.
Axle stands at the ready, kettle on, just gonna check there's no drive with a cold gearbox first.

 

[camerafodder]

For goodness sake Jonny take it easy mate. You're supposed to be convalescing!

 

[jonnyboy]

For goodness sake Jonny take it easy mate. You're supposed to be convalescing!

I am, don't worry. But then again I'm better off in the garage driving myself mad than in the house driving everyone mad!!!

Thanks.

 

[Dieselman]

I am, don't worry. But then again I'm better off in the garage driving myself mad than in the house driving everyone mad!!!

Thanks.

The Doctor has probably told you to start doing things as you normally would anyway...but at your own pace, which means you can stop when you need to.

 

[Dieselman]

So the plot thickens.
Popped the bonnet and found loads of strands of copper wire mangled (no insulation to be seen) around the viscous fan assembly. I'm reasonably **** about ensuring everything is connected back up before I start a replaced engine, weird.
Now wondering if a cable could have come off the gearbox = loss of signal/drive.
Axle stands at the ready, kettle on, just gonna check there's no drive with a cold gearbox first.

Isn't it a hydraulic 722.4 box, if so no electronics in play there.

 

[jonnyboy]

I think its a 722.353
The wire wrapped around the viscous is a red herring, total. Have had the car up and nothing is missing, gearlever linkage is still there. Lots of signs of oil leakage BUT the level is too high on the dipstick. Park and neutral "work" when the rear wheel is lifted so it is not a driveline issue, it can't be. Therefore it looks narrowed down to the gearbox or torque converter. What I cannot understand is that it was a total instant loss of drive, no big puddle/trail of oil up/down the street, and there is still far too much oil in the box according to the dipstick. I would have thought there would have been some warning signs/noises/etc. Only did about a mile and a half. Oil is clean, pink, and unburnt.
Car was cold this morning, no drive still. Idle speed is higher when cold, around 1100/1200 rpm, which drops to about 900 in drive/reverse.
Bonkers.

 

[NW_Merc]

Are you sure the box hasnt gone? When mine went there wasnt any real warning, just it wouldnt engage any forward gears but would engage reverse.

 

[jonnyboy]

Not sure at all to be honest. I don't know much about them but it would be an expensive swapover if it's an "easy fix". It just seems weird.

 

[NW_Merc]

My gearbox was hesitating before it went and then I lost drive altogether, Ian Walker opened up the sump to find lots of metal in there. Dont want to scare you but it might be a possibility the box has had it....

Is it a four speed?

 

[jonnyboy]

Actually mine is a 722.352

 

[jonnyboy]

Yes 4 speed. So no electronics.

 

[jonnyboy]

Does anyone know definitively how to tell the differences between different transmission codes? For example, whats different between a 722.352 and 722.358 ?

Cheers

 

[kth286]

might be a vacuum pipe slipped off the gearbox unit.

 

[219]

I wonder if the excess fluid has blown a valve or a seal somewhere (internally) ?

PITA though .

 

[kth286]

does reverse work ?

 

[jonnyboy]

No reverse. No drive.
Just spoken to Derek (druk) who has spoken with an autobox "god" who reckons chances are that the gearbox oil pump has gone. Caused by my ham-fistedness when I bolted up the box to the t/converter instead of the box and t/c to the engine - that 1/2" of play will damage the oil pump drive lugs. Am off outside in a bit to see if when it's running it p*sses atf out of a atf cooler line undone. If not then there is no gearbox oil pressure.

Still need to find out the difference between 'boxes, have found a 722.358 which is closer to a 352.