Thread: ZF replacement/overhaul options

Originally Posted by Blknight.aus

STOP....

have you got all the bolts out of the TC yet?

I get to the top bell housing bolts one of 3 ways.

if the underside of the vehicle is easy to get under and clean I use a wobble drive on a socket and an air ratchet.

IF its a filthy mess I send the owner under with instructions.

If the owners not available I do it from the top with a ratcheting ring open end spanner.


put a couple of long bolts in the bottom of the bell housing and slide it back about half an inch or so. then from the top secure a rope through the top bell housing bolt holes. have an off sider standing by to hold the weight of the front end of the box while your under it. IF you have a second off sider then lace a rope over the chassis rails and under hand brake.

assuming you dont have a proper transmission jack you can do it with just a trolly jack and a single off sider but I find 3 is better and safer.

Thanks Dave.
Yup - its a filthy mess and I'm the owner. Thankfully you've provided the instructions so under I go !!

The rope idea around the chassis rails is a ripper idea - unfortunately I didn't see your post until after the event.
I got it sitting on the floor with one helper, a small trolley jack, and a lot of "OK, its half out and I've run out of travel on my jack and blocks of wood to support stuff - what next!! ' type of thoughts.

Lunchtime today was spent at Total Tools looking at decent trolley jacks with more than 8" of travel.....

The worst part (apart from how I'm going to get it all back together again) is the thought that if its more than just the TC clutch its all gotta come out again for a rebuild

Steve

Well, the torque converter is off to Autoflite in Thomastown to get rebuilt.

Is there anything special that I should be asking for during the rebuild?
Any tweaks or bearing upgrades or anything?

Is it likely that they will be able to confirm when its apart that the lockup clutch was definitely worn out - and thereby confirm the cause of my lack of lockup on the road.

Steve

Ask them to seperate your exisiting TC and report on ti before they goto work.

you can get TC's with varying stall speeds and torque multiplication values. Speak to the guys there about your driving technique and what youd like it to do better.

The TC can also be rebuilt with a heavier duty lockup clutch.

The TC traps some crud from the box so can give a limited indication of whats happening inside your box. occasionaly the wear patterns of the vanes in there will tell a tale as well.

Thanks Dave - exactly the sort of info I was after.

Its behind a 300tdi, so not like it has to cope with big power/high revs etc, but I do use it for a bit of towing, so a heavier lockup clutch might be worthwhile.
I'll have a chat with them tomorrow and see what they suggest.

Steve

if you've had any tweaking work done it may pay to find out about getting the stall point shifted to where the engine is making peak torque. Thats not the best setup for ultimate performance but it will result in excelent towing and slow speed offroad work.

While youve got it out take the time to make up some guide dowels to help getting it all back together.

I also use a strong zip tie poked in through the flex plat-TC mounting hole thats at the bottom so that when you put it all together the little bit that you invariably miss the line up by will self correct enough for you to center it with a center punch/scribe.

The longer you make the lower guide dowels the easier it will be to get it all in and lined up.

Originally Posted by Blknight.aus

if you've had any tweaking work done it may pay to find out about getting the stall point shifted to where the engine is making peak torque. Thats not the best setup for ultimate performance but it will result in excelent towing and slow speed offroad work.

While youve got it out take the time to make up some guide dowels to help getting it all back together.

I also use a strong zip tie poked in through the flex plat-TC mounting hole thats at the bottom so that when you put it all together the little bit that you invariably miss the line up by will self correct enough for you to center it with a center punch/scribe.

The longer you make the lower guide dowels the easier it will be to get it all in and lined up.

No tweaking done yet unfortunately - it was next on the list before the TC started playing up. Just got my EGT guage in a few weeks back so I could start to do some tweaking.
Would it be reasonable to assume I'd end up with a similar torque curve shape/peak as the other pump only tweaks that have had dyno graphs posted here?

Just bolts with the heads cut off for guide dowels?

With the zip tie trick, I'm assuming you poke it through the flex plate and TC holes, then pull it out between the bellhousing and engine at the last minute before you start tightening the bellhousing bolts?

Steve

playing with the pump can give you nearly any torque curve and overall power you like (but it depends on if you want a nice fat big number or a nice long engine life)

if you follow their tune then in theory yes you get the same power as their graphs would indicate. If you havent had any work done yet, dont worry about it you may find that with repairing the TC you get back what you were missing and you may well be happy with that, If you suspect that its not going to be enough and you want to up the engine later talk to the guys who are going to rebuild the TC, they do this for a living, I know the theory of how it all works and what the mods do But I dont do them (its like I know the theory of brain surgery but I wouldnt want to be the poor sap who winds up with me slicin and dicing for their brain anurism)

I usually use something like 100mm bolts with the heads cut off . ground round and then with a slot hacksawed in the top so a screwdriver can be used to get them out. wind them all the way in as they can wind up supporting a lot of weight, if you dont get them in all the way you can damage the threads of your adaptor plate.

I leave the zip tie in all the way up it pokes out under the sump and if youve got it all close enough it will push its way out as you mate up the box. (the flex plate has a through hole and the TC has a stud hole)

Its a great visual aid, you can line up the holes of the TC and flex plate while the front of the box is supported and sitting back on the dowels if you use the strong white ones that are about 3mm thick and 10 or so mm wide 90% of the time they will line the holes up for you and the first bolt will wind straight in.

Just got off the phone to the guys at Autoflite Engineering. Very pleasant people to deal with.

I'm told converter is in quite good condition for having done 220K- the edges of the clutch lining are just starting to burn, but nothing else major.
He found no evidence in the TC to indicate that the ZF itself is unhappy

After a discussion about what I do with the vehicle, its going to get a full overhaul, with the addition of a heavy duty kevlar lockup clutch, replace the factory spline (which apparently are known for being soft) with a better one, and braze the stator?? Apparently the impellor is factory brazed but not the stator (I might have that wrong - could be other way round).
They also build up and re-machine the spigot that locates in the flywheel.
Normal overhaul I think was about $230, and with the better clutch etc its $275 +GST.

I'll have it back early next week.

Steve