Hydraflushing?

Post by **user_3150** » 28 Apr 2005, 11:04

Morning everyone, I am going to do a Hydra flush then Lhm change soon I was just wondering is it possible to syphon the old LHM out of the tank before filling with Hydraflush. I'm just being lazy and just wondered how much would come out this way instead of removing the tank twice?

alan s · Post by **alan s** » 28 Apr 2005, 12:30

Well the usual reason for using Hydraflsuh is because the system is full of crap.
The LHM tank has a white plastic disc in the bottom and the crap accumulates under that so if you just syphon it out, you get rid of the old LHM but then leave all the garbage in there which will be stirred up as soon as you fill with the flusher and can possibly block filters or wash some back into the system.
My Xantia had been dealer serviced before I got it and the LHM was supposedly changed withing a few klms prior to my purchase. When I got it the hydraulics just weren't right, so I took the tank out even though the LHM was the right colour and discovered not only was there a nice thick build up of gunk under the tank, but the amount of grit inside the tank was unbelieveable; I doubt it had ever been out of the car for a proper cleaning.
If you're going to do it, do it right and go to the trouble of doing the tank out twice.
If you're going looking for shortcuts, better off not doing it at all.
Alan S

Post by **user_3150** » 28 Apr 2005, 13:22

I wasn't looking shortcuts. I have never done it before, and have only had experiance on this type of suspension since I bought this car last August (so I have never done a fluid change). Now I know It doesn't work that way I will take out the tank and clean it fully before filling with Hydra flush. Should I replace the tank filter's (I belive there are 2) both times or just when I put the fresh LHM in?

Post by **martyhopkirk** » 28 Apr 2005, 14:11

The tank filters should be cleaned (using petrol) and dried off before returing to the tank.
Doint a Hydraflush this weekend on my BX - this is my first one too - used Westeron before now to do the job for me.
Good luck.

macaroni · Post by **macaroni** » 28 Apr 2005, 14:18

Popping my Hydraflush cherry this weekend too, very exciting!

alan s · Post by **alan s** » 28 Apr 2005, 17:15

Alec,
As has been said, the filters pop out and are washed in petrol and refitted. Watch for sharp edges on the lip of the tank and be prepared to prime the pump upon restarting.
I go a bit overboard when washing tanks as I feel the exterior can be a source of contamination for the insides under normal topping ups so I put it back in spotless condition.
If you have access to a compressed air supply, so much the better to blow filters claen and tanks dry.
Alan S

Oscar Too · Post by **Oscar Too** » 28 Apr 2005, 17:33

When Hydraflushing, make sure you keep the high-pressure return pipe off the reservoir until you are certain that what is coming back is Hydraflush and not LHM. I did my first H'flush late in the evening by electric light. What looked like H'flush returning in the light of a 60 watt bulb turned out to be LHM the following day. As a result I had a reservoir full of a pale green fluid with an orangey tinge, and a waste of J15. I had to do it again last weekend. (That was a complete other story by the way: left the car in high, took the reservoir off before I had released the pressure nut, got old fluid everywhere: I was suffering from a complete brain bypass...)

ActivaV6uk · Post by **ActivaV6uk** » 28 Apr 2005, 17:35

a metal flake effect in the bottom of the tank is normal for most cars now and nothing to worry about (as ling as the entire tank isnt like this), make sure the filters and tank are very well cleand out befor filling back up with LHM.
Andy

Post by **user_3150** » 29 Apr 2005, 00:15

Thanks for all your replies. I've only just got in from work. Marty & Macaroni ( until I looked properly I always thought it said Marconi)could you let us all know how you got on and how long it took. Oscar I won't do it at night done that too often on other job's then test drive with spanner's vanishing into the night or finding nut's on the drive in the morning. I'm a bit worried about leaving the high pressure return pipe off it sound's like I'm going to get coated in LHM/Hydraflush what actually happens? Alan S, the tank will be as clean as a whistle I have petrol and a high pressure airline. I'm a bit aprehensive but I am also looking forward to doing it.

paranoid · Post by **paranoid** » 29 Apr 2005, 00:43

Stuck flush in my new xant this afternoon, done flush and changed fluids before a couple of times, and the best advice was given by another member was, syphon off fluid out of tank first with a length of old hosepipe into an old oil container.
Makes the whole job a lot quicker and no mess
40 minutes from fully down to fully up!![:D] But I have done it before.

citronut · Post by **citronut** » 29 Apr 2005, 01:34

HI ALEC hyd/flush flushes the system when reinstaling L H M you clean the tank and filters again car must be on lowest setting throughout entire opperation best of luck malcolm

Post by **user_3150** » 29 Apr 2005, 02:26

Thanks for all the advice guy's feel a bit better about doing it now.

Oscar Too · Post by **Oscar Too** » 29 Apr 2005, 13:28

Don't worry Alec, it only squirts out a couple of inches, but you will need another vessel handy to catch it. Large yoghurt tub, jamjar, that sort of thing. Empty is best.
Let us know how you get on.
O

rg · Post by rg » 29 Apr 2005, 16:33

I did mine recently, and it's not a big deal.
Get hold of some clean ice cream tubs and jam jars to put bits like the filters, and, particularly, the manifold in.
Cleanliness is the key thing. Beware - the fliters have very delicate mesh.
Replace any OEM spring clips with proper jubilee clips where you can, but particularly the HP feed to avoid any air getting drawn in.
rg

adamskibx · Post by **adamskibx** » 29 Apr 2005, 18:46

Does anyone know how long you should leave the Hydraflush in there? I bought my BX with Hydraflush in a few weeks ago and have done about 700 miles- The hyrdaulics work amazingly. Should I change to LHM immediately or will the hydraflush carry on doing some good?