RE: power brake check valve caution

[Jim Grammer <jimg@domain.elided>]

I had an interesting experience a few weeks ago...fortunately it was just 
around my place, so no carnage ensued. Might save somebody's rear.

Went to move the '68 Travelall, it started fine, then I tried backing it up 
to the horse trailer for horsie in-out practice. All of a sudden she 
wouldn't idle, and pretty soon wouldn't run but just barely. By that time I 
had it close enough to the trailer and other projects to attend to, so I 
shut her off and didn't think much more of it(truck is off the road waiting 
for an engine rebuild). Turns out the plastic check valve in the brake 
booster vacuum line(the unit that 'plugs in' at the booster)had cracked, 
then broken in 2. Massive vacuum leak, and NO power brakes. I do not want 
to contemplate the results of this failure on the highway. The drum brakes 
on this truck are working overtime even with boost to stop the 31's, I 
suspect without boost I'd be dragging my feet on the ground as I ran into 
something. Normally a loss of engine vacuum leaves you with a reserve good 
for 1 stop or so in the booster can(the purpose of the check valve), but 
with the check valve busted in 2 you get no boost right now. Not good.

These check valves are a generic part that you can pick up off the 'bits' 
racks at most parts stores, and they're cheap. Considering what a hot 
engine compartment and time can do to a piece of plastic, I'd say replacing 
one every once in awhile might be a darned good idea.

Jim