Expert brake compensator

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Wookey
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Expert brake compensator

Post by Wookey »

I have a 1997 expert 1.9D upgraded (with the help of this forum) to 1.9TD circa 2003. That's still going strong, so well done to everyone involved. The van is used as a camper, not a Van.

My brake compensator is a bit sad. The arm is very stiff (although it does still move) and I can't get it off the vehicle for a good fettle without replacing all the brake lines as they are rusted into the unions. I've been wiggling and fiddling to get it through MOTs for years now so it's probably time for a new one (and a load of new brake pipe too).

So I have a couple of questions.
1) If I replace it how hard is it to adjust correctly? My manual tells me that I cannot DIY and it needs expensive high-pressure test kit. Is that really true, or can one get by by setting it by trying heavy braking whilst empty and full (I have a convenient straight, deserted rd less than a mile away for brake-testing). Will my helpful MOT garage be able to do using their rolling brake-test rig?

2) Is there any point getting a scrap one, or is it just as likely to be all rusted up so I'm better off buying new?

3) I understand that brake systems are normally split into two diagonals for safety. Presumably this is also true on the Expert and both circuits go through the compensator independently. Is that right?

4) Should there be any slop in the sprung actuator lever? Mine has always rattled about rather loose until I added a bit of rubber to take up the slack. IIRC there is a nylon nut and very strong spring, so it was impractical to remove all the slop by adjusting the nut. I guess this comes back to point1 - how exactly does one adjust these?

5) The correct part seems to be #486169 for £90-125, but there is also the #486163 used on the Synergie 1.9D. which is only £67. What is the difference? Did the 806 petrol and diesel models really use different compensators? (#486169 fits the 1.8i 806 as well as all the 1.9 Experts). Hmm It really does seem that the diesel 806 1.9 and Ulysse 2.1D used the cheaper 486164 compensator and the petrol 806 1.8 used the more expensive (nearly twice as much) one the vans use. How odd.

6) I also had a rear brake imbalance on last MOT. I understand from other posts that that's nothing to do with the compensator. I tried a good bleed and it only helped a bit, so I guess I should give everything a good servicing? Brakes are always annoying because they are hard to test at home.

thanks for any help you can provide. I'll have a good inspect this weekend.
Wookey
(2003-now:1997 Peugeot Expert stealth camper, 1991-2003:1987 C15)
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Re: Expert brake compensator

Post by jgra1 »

Hi wookey .i have a boxer /relay So a bit bigger .these are just my opinions based on that.

.I think testing with a brake tester is the answer.. but you will need something you can throw in the back to get the mass up to gvw to be sure.. speak to your local garage about that.. the brake stats may be in the driver's door shut. It's a very simple device and adjusting is very easy

A scrap one may be fine. If the piston moves ok.. maybe grab one from eBay where someone has removed it and can tell you it all is freed up ..

I don't know about the split system but as you say they usually split diagonally and therefore the pipes have to go through the compensator

Mine rattles when van has no weight ..I haven't checked now it's a camper

Brake imbalance may well be seized Cally on the back assuming disks.. one of my front ones didn't move at all
John

Disclaimer about kittens brakes PPE health safety etc
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Pug_XUD_KeenAmateur
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Re: Expert brake compensator

Post by Pug_XUD_KeenAmateur »

I've re-sprung the Compensator on my 405 Estate at least twice, which I'm sure is similar, if not the same. I believe its the same axle as a Berlingo, wonder if Berlingo/405 compensators are same part number or different....

....always just done the nut up til the spring seems reasonably 'secure' and then brake-tested it with some concrete slabs blocks in the back, always been fine.

...albeit saying that, my spare spring here, from the fella on eBay who re-makes them kept falling off for some reason, including within 30mins after fitting & brake test; never had that problem with the red car, which had one fitted too; bit of a mystery, I ended up putting a genuine one on. That was the MOT that I had a dozen advisories on, was I pleased?! :rofl2:

Never had cause to replace the Compensator item itself though and IMO surely the faffing is a small price to pay for all the aggravation.

I'm aware that one of these days I'll be having the back axle out to remedy the rot, which isn't too bad considered and I'm controlling as best I can; but y'know how it is, day 'll come to get the welder out, and I see disconnecting the brake pipes as one of the biggest potential challenges.

Is the weight of the fittings in a 'Camper' enough to tip the Brake Bias, I'm guessing not as you're suffering the Brake Bias issue, which I understand is very common and largely due to the rear brakes having a too easy life, but also the adjusters wear. I put new ones on mine, having realised some listed as for a BMW summat were identical; I did post the info here a long time ago, or can find the notes if need be.

Likely a few severe applications of the brakes on that stretch of road you mention with the blocks in the back 'll sort that soon enough (the further back you can get the weight, the less you need, but beware of it flying forward under braking g's and breaking summat) ; I've also been known to pull on the handbrake to about half ish for a half minute or so at 40mph-ish. You'll feel the difference afterwards. I usually manage only a very brief 'lock up' or two of the tyres. Need to do it myself actually, my brakes are sh*te atm

Maybe you can find something heavy that's part of the fittings to 'swap' (second battery maybe?) to put permanently within the extreme rear storage space, if available, so that the compensator rear bias is permanently 'on'.

Don't forget to check the condition of the Brake Pipes while you're under there, I cleaned, Kurusted and Hammerited some small areas just a few days ago.

PS: also check the Exhaust Back Box, I was well chuffed to pick up a new one for my 405 for just £22 in the last week or so, eBay, blooming enormous thing it is too... guess yours might be a cat though
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Wookey
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Re: Expert brake compensator

Post by Wookey »

Thanks for the tips. I've got drums at the back. I plan to take them off and have a good fettle this weekend so at least everything is moving freely and I can see if there are any obvious issues.
Wookey
(2003-now:1997 Peugeot Expert stealth camper, 1991-2003:1987 C15)
Wookey
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Joined: 28 Dec 2004, 08:43
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Re: Expert brake compensator

Post by Wookey »

So, I got a new (well s/h) compensator that's not seized and the unions unscrew. I had to cut the pipes to the old one because everything is too corroded to just unscrew.

Now I made a few brake pipes over the years (and have pipe + nuts+ flaring tool), but I've never joined one in-line. A couple of these lines run the whole length of the van (and are in reasonable condition) so an in-line joint seems sensible.
All the online videos talk about using a union nut with a mating surface and threads for two male nuts. My pipe came with male and female nuts. Is there any reason not to do a double-flare in the female nut and a single flare in the male nut and screw them together to make a joint?

Also lots of online examples talk about 'always use a double flare in brake lines', but everything I've ever disassembled has been a single and I've always done single to replace them, because they are going into things with conical surfaces where a single looks like it seals better. So what's going on here? When does one use a double flare?
Wookey
(2003-now:1997 Peugeot Expert stealth camper, 1991-2003:1987 C15)
Wookey
(Donor 2019)
Posts: 255
Joined: 28 Dec 2004, 08:43
Location: Cambridge, United Kingdom
My Cars: Peugeot Expert 1.9D (Camper conversion) (2003-now)
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Re: Expert brake compensator

Post by Wookey »

OK. New compensator fitted. Turns out to be an all-weekend job. Neither of the larger (M12) nuts would come out (until I got the thing in a bench vice after getting it off). So got to make up one new squiggly pipe and join one in-situ (which is a bit of a game, with fluid dripping out making the pipe slippery so the clamp on my easyflare was barely up to the job).

What I don't really understand is how to set the thing. It has this bizarre arrangement where there is a chunky spring with a spacer inside that is longer than the spring so the spring it normally just jiggling about. This results in the built-in slop to the device being about 1cm, and the range of the valve also being about 1cm. There is also a spring on the valve itself holding it 'up' (piston pushed in). You can push it a bit further in (couple of mm) or pull it out quite a lot more (8mm?). It's not entirely clear how all this is intended to work.

Here's a pic: http://wookware.org/pics/vehicles/exper ... nsator.jpg

The top is just attached with a plastic nut which is presumably never expected to take any significant load - it's just to keep the top end located. That is the only thing which would ever pull the piston out from the position the small spring puts it, so perhaps that long 8mm travel is never used - it's only the 2mm or so from the sprung position to 'fully in' that actually does anything. But that doesn't seem enough. The full suspension travel is at least 50mm. The mechanics of this thing being mounted about 2/7 of the way along the suspension bar makes the total travel of the bottom mount about 14mm. Seems odd if only ~2mm of that actually adjusts anything. And why the huge 'slop' region between pulling in and out?

Aha - maybe the point is that the piston moves out (down) when the brakes are applied and the proportionality is provided by the chunky spring pushing back? That actually makes sense.

As you can see, I don't get it.
Wookey
(2003-now:1997 Peugeot Expert stealth camper, 1991-2003:1987 C15)
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