722.9 Auto box problem. No drive at all. Any help appreciated.

[Jobsworth]

The splines are engaged, the inside of the gearbox will be turning. You however need oil pressure to operate the clutches that select the gears. You have no oil pressure because the two tiny lugs no longer spin the oil pump. Worse things happen mate. Could trailer it down to the south coast... bit of sun on yer skin, do you some good
Ps. I am Welsh, so it’s not an insult!

 

[Wolfie1]

So sorry to hear of the op woes but very interesting to read your info on it jobsworth

 

[Brian220CDI]

So sorry to hear of the op woes but very interesting to read your info on it jobsworth

It is fascinating even if I have just had to tell my misses this is gonna run to about £1500! I would rather document it lots on this thread so people can learn from my mistakes.

 

[Brian220CDI]

The splines are engaged, the inside of the gearbox will be turning. You however need oil pressure to operate the clutches that select the gears. You have no oil pressure because the two tiny lugs no longer spin the oil pump. Worse things happen mate. Could trailer it down to the south coast... bit of sun on yer skin, do you some good
Ps. I am Welsh, so it’s not an insult!

So that is why the error codes were leaning towards low oil level in the box as it had no pressure and if I had a Merc specific code reader that would have show up as low/no oil pressure probably.

 

[merc estate]

Blimey, i would get it trailered to Jobsworth he sounds like he really knows what he's doing, then relax till you pick it up. Number one rule never tell the wife how much things cost if you like them, it gives them ammo for another day. Good luck with it wow what a job.

 

[Brian220CDI]

Blimey, i would get it trailered to Jobsworth he sounds like he really knows what he's doing, then relax till you pick it up. Number one rule never tell the wife how much things cost if you like them, it gives them ammo for another day. Good luck with it wow what a job.

I think your right but at 225 miles I think I will find someone local. It would be a good trip to go and pick my fully working car up though.

 

[Petrol Pete]

OP Jobsworth has given you masses of advice that you can pass on to whoever you choose to do the work. At least the guys doing the work will know that you know (pretty much 100% now) what the fault is and you can have a sensible discussion with them of how to move forward.

I would still look into the cost of getting the car down to him, It might not be too bad £.

 

[Brian220CDI]

Ok so the car is getting picked up this week sometime by a local Autobox repair centre. Spoke to the boss as he's on call this weekend and he said he feels my pain. Told me he will get the box off to inspect it and then let me know my options but I think we all know which way this is going. One thing was nice to find out though was they have all the tech to rebuild the TCU's and reprogram Mercs etc as they have done a fair few so looks like its going into good hands! I think .

 

[jasonh]

I do feel for you. This almost happened to me with a BMW. I had the gearbox off to have the TC reconditioned. The BMW instructions had an explicit warning to make sure the lugs were engaged and there was a measurement to check. Mine seemed to be engaged, the measurement seemed to be correct.

Only when trying to get the gearbox back on was there a clunk as the TC slid back about 20mm and into place....If the jiggling to align the bell housing hadn't nudged the TC the same would have happened to me.

 

[Brian220CDI]

Update!

Jobsworth was right. I've absolutely smashed the lugs off the pump but he has given the all clear for a rebuild of my box after a check over, so he is going to sort the parts out tonight and get on with it.

Maybe get my car back on the road early next week.

Probably looking at a bill of around £1100 all in. Expensive oil leak repair

 

[geoffus]

Result then, thanks for the update.
Great diagnosis Jobsworth.

 

[Jobsworth]

Major lesson to anyone reading this, NEVER pull the engine out with the torque converter attached. You MUST unbolt the TC from the flex plate and leave it with the gearbox.

 

[Brian220CDI]

Major lesson to anyone reading this, NEVER pull the engine out with the torque converter attached. You MUST unbolt the TC from the flex plate and leave it with the gearbox.

Diagnosed 225 miles away. Well done I owe you a virtual beer you saved me £200 by me not sending the valve body off and a weeks wasted time waiting and fitting.

 

[Jobsworth]

Diagnosed 225 miles away. Well done I owe you a virtual beer you saved me £200 by me not sending the valve body off and a weeks wasted time waiting and fitting.

You are most welcome pal. Sorry I couldn’t bring you good news.

 

[Brian220CDI]

Just been to drop some parts off at the gearbox repairs and here it is

Should be ready Monday or Tuesday depending on when the oil pump turns up.

 

[CarFan79]

Major lesson to anyone reading this, NEVER pull the engine out with the torque converter attached. You MUST unbolt the TC from the flex plate and leave it with the gearbox.

Or if the torque converter sticks to the plate (as it can sometimes) make sure you fit it to the gearbox properly. It should drop down 3 clunks when fitting to a gearbox stood on end.

 

[Brian220CDI]

Car fixed and returned. £1150 in total. Big mistake I will never make again I just hope anyone planning the same or similar job that they learn from my mistake. Thanks everyone joining my painful journey.

 

[Brian220CDI]

Going into business making clocks! Does anyone want to refurbish their gearbox oil pump to a clock? I will only charge £1150 each?

This will be on my shed wall to remind me to be more cautious.

 

[Justintyme]

Major lesson to anyone reading this, NEVER pull the engine out with the torque converter attached. You MUST unbolt the TC from the flex plate and leave it with the gearbox.

And how difficult is to access the flex plate to unbolt it from the TC?

 

[Brian220CDI]

And how difficult is to access the flex plate to unbolt it from the TC?

Very easy. Black cover on the bottom of the gearbox about 20mm by 50mm. Spin the engine on the front pully and undo the 4 bolts 14mm if I remember correctly. I know now as I've learnt my lesson.