View Single Post
Old 06-05-2021, 01:12 PM   #14
jocko
Senior Member
 
jocko's Avatar
 
Join Date: Oct 2009
Location: Godley, TX
Posts: 17,936
Re: proportion valve or distribution block

It "looks" like you have a deep hole in the mc piston (indicative of a manual brake mc), however, the intermediate rod coming out of the booster is also long (which I haven't seen before...) (makes me wonder if in 67-68, maybe even thru 70, the power and non-power mc's were identical... hmm (i.e. all drum/drum systems). 71-72 power/manual mc's are not interchangeable, for example). If the member you bought this whole combo from said it was working and you've not changed anything, it "should" work based on the pictures above. One thing to check: I'd measure from the full depth of the mc piston hole to the mating surface of the mc - and then compare that with the measurement of the mating surface on the booster to the tip of the pushrod. The 2nd measurement should only be a "hair" shorter than the 1st. In other words, as long as the pushrod isn't engaging the mc piston when assembled - and as long as there is very little slop in between the tip of the push rod and the inner depth of the mc piston, you should be good. Also note that your push rood appears to be adjustable. I think there is nothing wrong with your arrangement, it should work - assuming the measurements make sense once you compare them. Is the pushrod fully seated in the booster in your first picture? (I assume yes). With all the info you've provided, seems more like a bleeding problem only at this point. You mentioned the brakes kinda work - do they feel "boosted" like power brakes should feel when you depress the pedal (even if braking perf is poor) - or do they feel the same as when you had just manual brakes before (but with poor perf)? Thanks for all the pics and sorry I missed the first set - they are helpful. One note on the bleeding process - you mentioned bleeding the mc, then at the block, then at the wheels. There should be no need to bleed anything at the distrib block, just mc bench bleed and then the wheel cylinders. I normally have an assistant do the pedal pushin, but many members have had success with gravity bleeding the brakes, might be worth a google on the site.

Last edited by jocko; 06-05-2021 at 01:18 PM.
jocko is offline   Reply With Quote