Leak Over Rear Axle

[Peter.N.]

Hi all

It's happened to me at last! I have fluid running off the underside of the axle just in front of the o/s wheel. As its accompanied by a cloud of vapour I would guess that its a high pressure pipe. I can't see it of course. I know a number of you have had this problem so could someone point me in the right direction as to which one and what I have to remove to get at it.

Thanks

Peter.N.

[noz]

Hi Peter,

Sorry to hear about your woes. You have two choices:

1) The bellows on the rear struts vent into the central steel tubular crossmember. If the first seal in the struts is passing badly then the second seal has to do all the work. If, like me, the bores of the rear struts have worn oval in shape then the seals can't hold back the pressure. The excess fluid vents up 2 little 6mm nylon tubes and into the inside of the crossmember. It finally appears out tof the crossmember ends just in front of either back wheel. The ends of the crossmember are hidden by the inner wheel arch lining. You need to remove them and shine a torch along the inside of the crossmember. If its wet in there then pull the little vent tubes out of the crossmember and leave them dangling in mid air. Then do a bit of Citroebics and watch to see which one is dribbling. The dribbling one indicates passing seals. Pleiades does repair kits but if the bores are worn oval they do no good. Only solution I've found is to replace the rear struts. I got a couple of second hand ones from the French scrapper. They were like new.

alternatively

2) One of the 6 or so high pressure hydraulic pipes is leaking as they pass over the top of the crossmember and disappear down behind the fuel tank. They are famous for rusting through here because the area doesn't get any through flow of air and is permanently damp. It is nigh on impossible to get to those pipes to either replace them or repair them. That is, unless you drop the rear subframe. Now that's no where near as bad as it sounds. The whole subframe is only kept on by 4 bolts. My good friend DJ taught me that if you remove the two bolts on the nearside completely and undo the two offside bolts by, say, 10 turns but don't remove them then the subframe drops nicely out of the way and access is dead easy. I know you have a flaring tool so just find the leaking pipe and put a joint in it, replacing the rusty section. I've jointed a couple and I've arranged the joints such that they are located to the front of the crossmember at the lowest point just before the bundle of pipes go into the plastic tray which shields them from there to the fornt of the car.

Please let us know what you find.

Cheers

noz

[Peter.N.]

Hi Noz

Thanks for the info. It sounds like option 2, as there is oil mist in the air around the top of the crossmember, and I can see what you mean about not being able to get at them. The only way I could see was by removing the fuel tank, so I'm glad I asked!

I was surprised as the pipes were quite oily, I squirt oil up there when I am underneath as I do inside the chassis members, but when I looked round the back of the crossmember they were quite rusty.

I orderd some pipe and fittings today, so may be here tomorrow.

Peter.N.

[rg]

I've done this twice on my 2.5.

I have photos.

It wasn't as bad as I thought!

It's worth changing the anti-sink sphere whilst you've got the subframe down!

r

[Peter.N.]

Thanks r, but I dont have an anti sink sphere, in fact none of mine have had!

Peter.N.

[Peter.N.]

Hi Noz

Dropping the subframe was simple, thanks for the suggestion. Finding the leak was also simple, what isn't is getting the union undone. The pipe goes into a 'Y' shaped 'T' piece, if you follow, and the union is securely rusted in. I have had a pair of molegrips on it while holding the junction with another pair, but all its doing is wearing the union away. Neither of the other unions will come undone either so I cant take the junction piece off. At this point I would normally weld a larger nut over the fitting so I could get good hold of it, but because of the proximity of the other pipes, some flammable, and the fuel tank I am reluctant to try.

Any suggestions?

Peter.N.

[wirdy]

When mole grips fail I resort to my small monkey wrench, however it will bite into the union and distort it terminally. I find the monkey wrench action of getting tighter with the more force exerted is exactly what brake unions need to crack them.
Good luck.

[noz]

Hi Peter,

The only true solution I've found to rusted pipe unions is heat. Even if you get the best mole grips all you will do is crush the thin-walled unions and then grip the pipe. When you turn the union you will also be turning the pipe. Tha's no good if you only want to remove one of the three unions on the y-piece.

Use a bit of flameproof material, tin sheet or aluminium sheet behind the y-piece and heat the union. Failing that, there's enough slack on all the pipes to cut all three very close to their respective unions and then remake the ends. Once the y-piece is off and in your hands you can heat it with oxy-acetylene and the unions will come out no problem at all.

cheers

noz

[Peter.N.]

Hi Noz

I think part of the problem is that the 'Y' piece is only held in a plastic bracket, so to get a good purchase on the union I have to hold the fitting with another pair of mole grips. I will see if I can disconnect the other end of the pipes and take the junction piece off, the problem being of course that all the unions are rusty. Failing that I will try my usual welding trick. Its probably partly the application of heat that frees it up. If you see the red one disappear from my signature, you will know I set fire to it.


Wirdy - I think that stilson type grips would be a lot better, but unfortunatly there isn't sufficient room to get in there with them.

Peter.N.

[steelcityuk]

A plumbers heat proof mat is useful for this kind of thing if you can get it in place and keep it there. I use a 'Aston Super Wrench' on difficult fittings but as noted before if they are corroded in place then only heat will work I've found.

Good luck with it.

Steve.

[rg]

Draper produce a small blow torch, refuelable with lighter fuel, which is ideal for confined spaces where a plumber's lamp is too big and risks turning you into a safety video victim.

They are an utter bugger to get running smoothly due to sloshing of fuel, but once established, give a powerful, focussed flame.

Oh,and releasing fluid can work wonders. Don't ask me how. Since the demise of Plus Gas, I've been using the Halfrauds stuff.

r

[steelcityuk]

Our local indie still has Plus Gas, still the price is high, could be old stock I suppose? Last tin I had I dropped it on screw and it punctured the can, it was brand new too and cost me £4.85!

Is the freezing spray any good? Anyone tried it yet?

Steve.

[Peter.N.]

[demag]

I see the rubber seal is still in good nick will you be re using it?

Peter are you doing all this on those old scafold planks and oil drums?

Just be careful mate. As valuable as our old cars are, our old club members are even more valuable.

[Peter.N.]

Hi Dave

I was amazed that the seal was still intact, it got quite hot, but I did use a new one. And yes, I did do it on my 'ramp' but they are not scaffold boards they are about 18" x 3" albeit a bit rotten - I am going to get some new ones - I've had those about 35 years - I'm on my third pair of oil drums! Thanks for your concern.

Peter.N.