I have a '74 Chevy 3/4 ton p/u, and I have a problem that's been driving me
crazy!! It loses fluid from the rear reservoir of the dual MC, and overflows
out the front! I tried swapping the MC...no dice. Then, I found out about the
disc/drum pressure modulator valve, down on the front I-beam assembly. No
store carried them, at all! I finally broke down and went to the dealership,
they had two in stock, brass, $80 each. Yow! But, I paid for it, installed
it, and it worked fine for 2 months...then, back to the same ol' problem! I
alleviated it somewhat by cutting a channel between the front and rear
reservoir, so when I accelerate, it will pass from the front ( overflower )
to the rear ( loser ). But it still doesn't solve the problem. Has anyone
ever run across this before, and know what I should try next? Maybe the
modulator pressure balance valve went bad again, but I'm not eager to pony up
another $80 to find out! Maybe I"ll hit a junkyard and get a couple of used
ones to try out, see if that will solve the problem. Is it possible one of
the calipers is locking up, and not passing fluid, so the pressure gets too
high and it pushes past the valve? It seems to stop ok, although not
exceptionally quick...I've driven similar year trucks, and those brakes seem
to be more sensitive than mine is. Any suggestions appreciated, thanks!
My move to my new house is halfway...got the girlfriend moved in, now to
move my stuff from the stinkin' townhouse. So I'll have a place finally to
work on the ol' '55 Suburban once I get some other projects finished, which
are closer to completion. Yee-ha! Well, TIA for any help. Bye!
New two-car ( er, truck ) garage owner with detached house....
oletrucks is devoted to Chevy and GM trucks built between 1941 and 1959