Leaking Pressure Regulator

roscoe · Post by **roscoe** » Wed Apr 18, 2007 12:42 pm

This weekend as I was doing an oil/filter change and installing my oil temp sender, I noticed a bit of LHM under the PR. I cleaned it up and after starting the car, watched carefully to see where it was coming from. Appears to be out the back of the PR where it bolts to the mounting plate - tightened the single bolt up a bit but made no difference. As the PR operates with pressure, I can see the LHM ooze out, then stop until the PR pulses again. My question is - can the PR be overhauled - I know there is an O ring in the back of it behind a plate held in with a large circlip? Are there repair kits available or is it a standard size O ring? I have a spare PR from my parts car but it's a bit of an unknown quantity - only had that one running for a limited period of time so don't know if the PR was good or not.

jeremy · Post by **jeremy** » Wed Apr 18, 2007 1:59 pm

From what I remember the bolts securing the PR to its mounting simply pass through the casting - and have no contact with LHM.

I don't think there are any holes on the plate side to leak. Citroen list part numbers in their manual but do not list an overhaul kit. Most of the bits sealing it are standard - looking like 'O' rings and ball bearings so if you can get it to bits then you can probbaly eventually source bits.

However PR leaks are rare - but other things give the impression its leaking - like input and output pipes - which need to be straight, not tipped - and tightened correctly (ie not very tight.) I've had a leak on my TD from the curved pipe coming from the bottom which was due to the bend on the pipe finishing at the end of the securing nut - and not allowing the pipe to sit straight. It may be that a pipe simply needs nipping up.

Another cause can be a flat accumulator which causes a very severe pulse in the pressure as there is no accumulator to damp it.

roscoe · Post by **roscoe** » Thu Apr 19, 2007 12:29 am

Thanks Jeremy
The leak is from the back of it where the single bolt goes through the large mounting bracket into the PR. I've checked and cleaned all the pipe fittings and they are not the culprits - it is definitely coming from around the piston cover on the back. The accumulator sphere is fairly new - tick time is around 45 seconds or so which likely rules that out as the cause.
I'll remove the mounting bracket this weekend so I can see the back of it better and see if it is pushing LHM - if so will try and source an O-ring locally. Gabor's site tells how to rebuild them but doesn't say anything about where to get the O rings so hopefully they are a standard size..

AlanS · Post by **AlanS** » Thu Apr 19, 2007 12:46 am

Roscoe,

I understand Roger Parker in South Australia has the kits made up for them. Closer to home have you tried Wongy at AutoFrance at Artamon?

I just ordered a pile of mechanical bits from Caravelle in Melbourne but he couldn't help with things like octopus etc. I rand Wong and he had them on the shelf, so he may be worth a call.

Alan S

roscoe · Post by **roscoe** » Thu Apr 19, 2007 10:32 am

Thanks Alan
I have to get hold of Wongy anyway - need a lower engine mount bush and he has them in stock so will see if he has a regulator kit as well.

DLM · Post by **DLM** » Thu Apr 19, 2007 5:59 pm

I have exactly the same happening at present - though less pulsing (better accumulator) has maybe cut down on leakage

roscoe · Post by **roscoe** » Mon Apr 23, 2007 7:02 am

I picked up a new lower engine mount bushing, O-ring for the PR, and some new pipe seals from Wongy at AF today - so my next free day will be spend doing some overdue maintenance

Wongy figures the O-ring will be the culprit so as long as I can get the piston and spring out of the PR without it flying into space...I should be right.

roscoe · Post by **roscoe** » Wed Apr 25, 2007 8:47 am

I replaced the O ring in the PR today - was gong to just swap regulators with the one off my parts car but it was a bit of an unknow quantity so I used my original one from the TZD. Bugger of a job - would have been easier with the rad out but I got it done. Put the PR in my vise with a nut on the cap end to compress it so I could get the circlip out - it is VERY tight!. After I managed to pry it out and get the thing back out of the vise with out bits flying everywhere, gave it a good wash in petrol, blow out with compressed air, put in the new O ring, soaked everything in new LHM and reinstalled it. After cleaning up the mess from the LHM dripping out of all the disconnected pipes, started it up and Presto - one less leak! That sorted the leak problem out, now it's onto the lower engine mount bush - question - to change this do you need to remove the fork bracket off the frame or just lift the engine so the fork clears the bush? I tried to remove the bolt through the crossmember that holds the fork on and it's rusted up pretty good plus is an 18 mm which is one spanner size I don't have

and I can't get an 18mm socket on the nut on top of the crossmember, the front height corrector fouls it.

jeremy · Post by **jeremy** » Wed Apr 25, 2007 10:11 am

The bush in the yolk will probably need changing as well. As its secured with a bolt and nut (as opposed to being threaded) you can always grind the head off and replace the bolt with a new one to the correct spec (I would have thought that reasonable quality one was required rather than sort of fence quality) You would of course have to make sure that there was sufficient room to get the bolt out between the bracket and the floor.

When I did mine it came undone after a bit of persuasion but I was probably using an 18 inch breaker bar (less chance of bashing my knuckles as I don't have to pull too hard) and would have had a tight fitting spanner on the top.

Some plus gas or oil applied a while beforehand may help.

It'll help to deep freeze the new bushes and fit them straight from the fridge. This shrinks the outer ring a little which makes them easier to get in straight.

roscoe · Post by **roscoe** » Wed Apr 25, 2007 1:44 pm

Thanks Jeremy
I hadn't thought about grinding the head off the bolt and driving it out - will measure it next time I'm under there to see if it will clear the floor if I do that. Will buy an 18mm spanner first though and try to get it off that way - have soaked it in WD40 today and will keep that up for a week or so. I already have the large bush in the freezer but haven't got the small one - is it a readily obtainable part or are there aftermarket ones available?

DLM · Post by **DLM** » Thu Apr 26, 2007 1:50 pm

Reading all this with interest, and appreciate your bravery in going straight into the job, roscoe. I'm planning a reg swap, as you were before starting this.

roscoe · Post by **roscoe** » Sun Apr 29, 2007 12:31 pm

The hardest part is getting the lines loosened so you can undo them without rounding off the fittings - my TZD came from the UK and so has the ever-present rust underneath on all the fittings - unlike my old 16V 'Aussie' car that was clean and you could almost take everything apart by hand. Lots of penetrating oil, the correct size pipe spanners (not a normal one or you will round off the fittings!) and it should be OK. Once the regulator is off, it doesn't make much difference whether you swap it or fix it - using a vise and a good strong fine screwdriver to pry out the circlip only took a few minutes - the rest is easy. Putting it back together is easier than taking it apart as well (the PR that is), putting it back in the car is a bit fiddly if you don't have another set of hands to hold things while you start screwing in the lines ( I used new seals on all of them as well). Suggest you get all the lines started by hand before mounting the PR to the engine, once they're in, then bolt it down - and use a pan underneath as lots of LHM keeps dripping out of the lines!