Monkeylad Madness!

[Bernard Littau]

Hi Stephane,

A rear wheel lock up under straight line hard braking with minimal traction,
or a left rear wheel lock up under hard braking on a left turn would be the
problems you might see without a functioning brake proportioning valve.
(The right turn issue is covered by the other brake proportioning valve
mounted more in the middle of the car, on the body, between the right and
left rear wheels)

In normal driving on dry pavement you would not likely notice the presence
or absence of the proportioning valves.

The Bentley, in the section on adjusting the spring tension on the first
proportioning valve, does talk about using the valve to balance
understeer/oversteer when braking in a corner.  You might read that section
and make your own conclusions.

Best,

Bernard Littau
Woodinville, WA
'88 5ktq



> While checking over the underside of the new 88 5ktqa on Sunday, I notice
> that some of the brake lines are wet.  I look a little closer and
> something
> just doesn't look right...oh, there it is, or should I say "there it
> isn't"
> ...there was no brake proportioning valve...?!?  Also, at the tee that
> splits the brake fluid to each wheel, 2 of the fittings have mucho threads
> exposed, while the 3rd is in deep, with few threads exposed.  The source
> of
> wetness is clearly visible as being from this tee.
>
> When I bought this car last month, it came with a whole bunch of service
> records with a recent one for major brake work including:
>
> diagnose and repair brake failure
> new brake pads and rotors
> new brake lines
>
> no mention of proportioning valve and I am suspecting that they took it
> out
> when they did the brake work and never put it back in because it was
> likely
> seized.
>
> Am I the mad one here, or should there be a proportioning valve?  FA shows
> one the same as on my 86 5ktq sedan (which is there, BTW).  If this is a
> safety issue, I think a 'chat' with the monkeylads would be in order.
>
> And the million $$ question, what should be expected from lack of this
> valve?  So far I haven't noticed any difference in braking from my 86 to
> my
> 88. (maybe this means the valve on the 86 is NFG?)
>
> On a positive note, the new flexible brake lines and rotors look really
> nice
> :)
>
> Stephane
>