I recently had to replace the metering valve on my '69 442 as fluid started leaking past the seal at the rear of the valve. No problem, replaced the valve and got it buttoned up. I noticed I wasn't getting any fluid dripping in the line from the master to the valve and thought that was interesting (I expected to have fluid leaking from that short line). I've bled the brakes on this car numerous times over the years and never knew the recommended procedure was to 'open' the metering valve while bleeding. I happened to reference the CSM and it mentions this. I understand why it would make the process a little easier, but I've obviously bled them before without opening the valve. Just curious if anyone's done it both ways and has information that pushing on the rear of the valve to open it is in some way 'better'?
The CSM references a unique tool to be used to hold the valve open during bleeding. I'd have to fabricate something to do the same function but it doesn't seem necessary. Comments are welcome!

 

I've been bleeding the brakes on these cars for over half a century and I've never held in the button on the metering valve. Never had a problem.

 

Thanks for the reply. Another example of the wealth of information in the CSM - even if the 'recommended' procedures aren't always necessary.

 

Hello acavagnaro,
Thought i would share a few things given i am going through what sounds like some of the same brake issues. That and i cant sleep with to much technology at my fingertips.
The nostalgia of my old machining days crept in and for what it is worth, i discovered the machining of the internals on these after market "same as original" metering valves are not as accurate as one might hope. To the extend that it may effect their operation.

Other than the visible tool chatter (picture set 1), You can see the land that the wavy washer rests on (picture 2), intended to isolate the smaller spring force to the internal pin (picture set 3), is not correct and is recessed compared to the original (back to picture 2). What appears to be an intended initial minute delayed duel rate action force imparted in the system, now can not happen given the machining tolerances will allow both springs to engaged the outer metering cup at all times (picture set 4). No idea if those terms are accurate for the part, but i think they describe the components well enough for you to get the idea. I also don't know what practical effect this may have (probably non at all) but, when i find one tolerance defect i tend to not trust the rest of the part. i.e. the hole/metering accuracy is garbage on the replacement and you can see the originals are beautifully chamfered (comparison in picture 2). Oh and. ignoring that the replacement wavy washer is garbage and who knows the rates of the replacement springs are correct despite their pretty new cad look. My love affair with old machining is showing, i digress..
The solution i settled on, to cannibalize the needed seals from the aftermarket part and rebuild the old part. Evaporust worked great and the original components came out looking new. Testament to 69 ingenuity, the year we went to the moon , on math solved with slide rules .

Any way, maybe this helps, most likely useless knowledge, at least worth the affirmation that they still don't make em like they used to. Not to mention replacement seals have become quite expensive with extra "packaging".

Happy motern,


(1) Original

(1) Replacement

(2) replacement left, original right

(3) replacement

(3) original

(4) replacement

(4) original