Technical How to free up load proportioning valves?

[exciton]

Hi All,

Car just failed its MOT - boo!

Rear radius arm bush - just order a kit from Shop4Parts and the rear brake load proportioning valves (?) on both sides - apparently some levers we not returning (?). The mechanic said these could just be freed up. As I am going to try and do this myself can anyone describe what these are and how I go about freeing them up? A good squirt of WD40?

Thanks in advance,

Mark

 

[rpaterson]

A good squirt of WD40 never hurts. Give them a shoogle around as well so that they're using the full range of their movement. My (not so) local MOT place freed up these valves for my neighbours 206 when we took it up. I don't know if this would come under 'minor adjustments' that they have to do nowadays.

 

[exciton]

Hi there,

Crawled around tonight and sprayed everything I could see with WD40. Anyway after a fair bit of banging and tugging I think I finally managed to free up the little sods. Now the two flaps/levers on either side move and spring back when released. However, looking at the set up I think there should be a spring from each compensator valve lever to a bracket on the suspension but these were missing - the spring in the picture below from Eper. Stupid question but is it needed to pass the MOT as I guess it is a part that I will have to order and may take a few days to come through.

Thanks

Mark

 

[rpaterson]

Although I can't see it too clearly, I'd assume that the spring is judged to be a part of the system and should be there. It will be some kind of return spring that comes into play when you don't have a bootful of cement bags.

 

[exciton]

Hi,

i have been in touch with Fiat and yes the springs should be there - nor sure how it passed its last MOT (before i had the car) as there was no way those valves just had 12 months worth of 'corrosion' on them.

anyway springs are on order £4 each which seems a bit steep but if it helps getting through the MOT a bargain!

Mark

 

[Ralf S.]

The springs just hold the arm at a tension. If your arms were a bit stiff, the rust may have been doing that job.

You won't fail MOT for a missing spring, you'll only fail if there's insufficient operation at the rear brakes (minimum is 13% of total brake effort, I think) so your lad may have passed even without the springs.

The old springs probably went rusty.. and when they rust too much they stop becoming springy.. they stretch and then don't go back to their static length.. so they stop acting like springs.. eventually they become loose and fall off.

So, grease your new springs to buggery. That'll keep them doing their springy stuff for years to come.


Ralf S.

 

[exciton]

Some good points and thanks again Ralf for all your recent input.

Just got to get the old radius arm bushes/bearings out now - I just need to find a suitable drift and try not knacker a socket or similar.

Cheers

Mark