CitroJim's AX, C3 Picasso, Cycling and Running Tales

MikeT · Unread post by **MikeT** » 03 Nov 2009, 13:32

I would just like to say thanks for taking the time to take and display all these clear photos for the rest of us interested forum members that have never delved into the depths - I, for one, can certainly appreciate the extra work involved!

Unread post by **CitroJim** » 04 Nov 2009, 17:46

Thanks Mike

There follows some more pictures...

Grrr

not enough progress today and little tomorrow as I've been called back to work to attend to something urgent

Still, there has been progress.. Hopefully, I'll be free again on Friday and I've negotiated replacement days off next week..

First up [on vehicle work] was to attend to the LHM leak on my V6. It was not bad but just bad enough to cause a drip from the bottom of the rear hydractive sphere and occasionally drip a little onto the drive. You all know how I absolutely hate leaks

The source was the hydractive electrovalve. Replaced and all is now LHM-tight again

Onto the gearbox...

I started by having a look at the hidden swarf collection magnets behind the diff. This is what I found

I thought two startled cats had got in there...

That is a LOT of swarf. More than I could account for. I cleaned the magnets and went in search of the source. Before I reveal from where, here's some nice clean magnets...

I began by disassembling the F Brake and then, on removal of the piston, I found this:

The output gear bearing has broken up and shed a lot of swarf. The bearing is black and it's surrounding blued. It has damaged the phosphor bronze bush within the shaft which supports the input shaft. The bearing, as expected, is noisy and has huge play.

Here is a close-up of the bearing:

I now have a good idea of what happened. This bearing started to break up. The swarf collection magnets did a good job of catching a lot but not all. the bearing is in close proximity to the oil pump and a path exits for swarf to enter the pump via the torque converter tail. The bearing on the converter tail is splash lubricated from oil that would be swarf-laden. Bits of swarf got into that bearing and caused it to fail and weld up.

I hate to think of the cost of a new output shaft and bearings as it is part of the output gear assembly. Luckily, I have a good one in my scrap gearbox.

It would be easy to miss this failure as it is hidden behind the F Brake, which needs special tools to disassemble. Failing to notice this may be the reason why some gearboxes that have suffered an apparently similar failure have failed again soon after. It would be easy to miss...

One good thing is that the oil filter has done it's job very well and despite all the carnage found thus far, there is no swarf apparent anywhere in the sensitive parts of the gearbox.

Off now to start stripping my scrap 'box to retrieve the good output gear from it...

superloopy · Unread post by **superloopy** » 04 Nov 2009, 17:59

Fascinating

Daveid Attenborough's 'LIFE' or Jim's 'V6 Gearbox Rebuild'?

The latter wins hands down for me even though it's not a job i'll EVER contemplate doing

Those pictures just bring the whole thing to life, keep-em coming Jim

Unread post by **xantia_v6** » 04 Nov 2009, 18:24

I assume that the failed bearing is the cause of the occasional vibration at 90+MPH uphill (on European motorways). If so, it has done at least 2000 miles like that.

How is that bearing lubricated?

The burning of the bearing might explain why the oil is much dirtier than last time I checked it 6 months ago.

Unread post by **CitroJim** » 04 Nov 2009, 18:36

xantia_v6 wrote:I assume that the failed bearing is the cause of the occasional vibration at 90+MPH uphill.

Yes, it could well be the reason as we saw the intermediate driveshaft bearing is in perfect order.

The bearing is lubricated by splash/mist.

Deanxm · Unread post by **Deanxm** » 04 Nov 2009, 20:56

Hi Jim

Exellent work and writeup as usual, seems the cause of this failure was the same thing that can kill any transmission then.

Daveid Attenborough's 'LIFE' or Jim's 'V6 Gearbox Rebuild'?

The latter wins hands down for me

Indeed, ive come back from our new house to the flat where my internet is just to see this threads updates!! although David attenborough is a close second

D

Unread post by **CitroJim** » 05 Nov 2009, 21:59

Not a very exciting one this evening

Despite having to work today and Thursday being my evening with the girls, progress has been made.

I've recovered a serviceable Output gear from my spares 'box and am now ready to start reassembling following the arrival of all the spares. The torque converter would also have arrived today had I been home but TNT are redelivering in the morning. Considering it was picked up for it's trip to Glasgow on Tuesday and back on Thursday, that's not bad. The rebuild was done by Mackie but under the auspices of Automatic Choice who really have proved to be a top company to deal with.

No more damage has been found and no more swarf either

I did, last evening, have a brief foray into my scrap valve block. I tentatively undid a few screws to release a plate covering some valves and thankfully was ready for there being a very big spring underneath. My jury is still out as to whether or not to dismantle the valve block given that I can find no evidence of swarf contamination in the vicinity. One thing I was pleased to find was no contamination appears to have affected the cooler. Good job too as I priced up a new cooler and nearly fell over. It costs over £200

One small error. The output bearing (the failed one) is semi-pressure lubricated from a drilling along the input shaft that jets oil up into the middle of the two taper rollers that comprise the bearing set. I'm not sure of the exact source just yet but I suspect it is a drilling off the gallery that supplies the torque converter. I shall blow all the drillings and galleries with air to ensure they're 100% clear during reassembly.

Tomorrow is a clear day so I hope by the end of it to have the 'box back together.

lexi · Unread post by **lexi** » 06 Nov 2009, 18:53

Last auto I had was a Jatco on a big Patrol. It had a gauze in the sump and a nifty sedimenter filter tray ( £20) that came off after removing sump. At 150k or over however the ATF fluid cooler element in main water rad could block up with swarf and kill the tranny.
Prevention was to fit a couple of aftermarket Mocal type coolers and bypas the original. This took transmission to 250k easily.

Issues above seems to be similar to the Landrover ZF boxes........probably different box to Xantia V6

Where and what type of cooler has the ZF Xantia box Jim?. Is there no way to flush out all the fluid in that box by undoing the in and out to the cooler. Feed it in through a pump from 20litre drum until all the old comes out and the new stuff flows through ie all old fluid is out.
Engine is normally started to do this and therefore fluid in the TC is emptied and replenished in a continuous flow.

Maybe there isn`t the room?

Unread post by **CitroJim** » 06 Nov 2009, 20:36

The 4HP20 has a very fine internal filter Lexi. You can see it in the PictorialI have just created of todays work.

It has a water oil cooler and it's mounted on top of the 'box. It's frightfully expensive to replace but luckily gives little problem as the efficiency of the filter keeps it clean. If you have cooling problems though that can fill the cooling system with sludge that can wreck the cooler.

The method you suggest for a total fluid change is possible and for this there is a convenient (ish) external pipe you can get to. Access is not easy so it's generally not done. A couple of partials at regular intervals seem to be the easiest way.

Today has been good despite being called into work again for an emergency job. Luckily it only took an hour and did not impact too much on my work plans for today.

The 'box is all back together and is documented pictorially here.

Tomorrow, all being well, we'll reunite it with the engine and get ready to reinstall the engine and gearbox in the car.

lexi · Unread post by **lexi** » 06 Nov 2009, 21:41

Ok Jim. Just chewing the fat

Great blog by the way.

vince · Unread post by **vince** » 06 Nov 2009, 22:25

Dont know about anybody else but i was just wondering when NASA are going to call you in to give their aged space shuttle fleet a check over

How did you learn all this stuff

I loved your casual apporach on the LHM leak on your rear electrovalve....almost "oh yeah it was leaking, so i just fixed it"...Most of us would be like "Oh My God, whats wrong!!!"

P.s. On your comment of having a taste of what setting up on your own would be like, I work with garages every day, trust me, they havent got half the knowledge and "thoroughness" (thats not a word i know) that you have / put in on these vehicles

Malcolm if your reading, your exempt from this

Sl4yer · Unread post by **Sl4yer** » 06 Nov 2009, 23:21

vince wrote:Dont know about anybody else but i was just wondering when NASA are going to call you in to give their aged space shuttle fleet a check over

They'll never do that Vince. He likes to do things properly...

James

Unread post by **myglaren** » 06 Nov 2009, 23:32

Bet you'd like to get your hands on this little beauty Jim

Unread post by **CitroJim** » 07 Nov 2009, 06:45

Wow! that's an engine and a half Steve

Vince, I'm entirely self-taught on all of this. Well, not strictly as I learned lots from dad right from being a toddler. He did much the same as I do these days although his specialism was in 1960s Austins.

To reassemble the gearbox alone took all day yesterday, solid work apart from the time I had to go to work. I'm not a slow worker but the time and attention I pay to a job like this would never work out economically in any sort of business environment. At reasonable labour rates, my time on this job has already passed the £1,000 mark and there's still some way to go. Cost of parts alone has come out at around £500. Unless you can do the work yourself, the cost of resurrecting a V6 with a duff gearbox is massive. I reckon if it were done professionally you'd be looking at a cost in excess of £2,000.

I guess this is why the garages have to cut so many corners as to do otherwise it would bankrupt the customers and make a garage business non-profitable.

XantiaMan · Unread post by **XantiaMan** » 07 Nov 2009, 09:26

vince wrote:On your comment of having a taste of what setting up on your own would be like, I work with garages every day, trust me, they havent got half the knowledge and "thoroughness" (thats not a word i know) that you have / put in on these vehicles

Your absolutely right there, i've worked in many garages over the years and very few of them have Jim's laid back and logical approach to problem finding.

Weather is looking ok today for an engine/gearbox refit Jim... Good luck!