Now that I am back from vacation I had the chance to go over my truck after it lost it's brakes while driving. Removed the master cylinder and found that it operates normally. Re-installed it and then bleed the brakes to see what happens. After one go around the pedal still goes all the way to the floor before the brakes catch hold. So I go around and bleed the system 3 more times and still the same thing. The pedal all the way to the floor under steady pressure. Feels like there is slight resistance as you push the pedal and slowly force brake fluid out somewhere only it isn't leaking anywhere. At this time I'm still puzzled as the pedal was fine right up to the first time it went straight to the floor.

 

Pop the cap off the master and have someone else pump the brakes for you slowly. Look for fluid being forced back into the reservior as the piston is moving down the bore or running out the backside into the cab interior. That is a pretty common problem with the master cylinder. If no fluid rushing back into the master then still have the other person pump the brakes slowly and look at all your soft lines. You could have an internal leak between the inner and outer line.

 

I'm thinking like Mark that you have a bad master cylinder.

John

 

I agree with the consensus it's probably internal valving of M-Cyl "by passing" under any sort of loading.

Mike, FWIW
I'm working on BU# 01747, a TBF-1, used in ASW service in the N. Atlantic then put in Lake Michigan during a water landing in May of '42 During training, by an Ensign who believed he had an on board fire. He didn't. He had semifores behind his starboard exhaust collector that were burning. Seems the deck crew would stow the flags there during exercises.
I am also "tweaking" on another Grumman, BU# 161426 an F-14B/D fitted Tomcat we recently acquired & put on display from the USN.

FBp

 

My 66 did the same thing, I checked the m/c nothing looked wrong, replaced it anyway, brakes worked fine.

 

Just ordered a new master cylinder based on this info as there are no leaks anywhere. Did notice fluid against the firewall around the master when I pushed on the brakes without the cap on. Thought I had pushed very slowly yet saw brake fluid dripping down the firewall.


I see an early production TBF. Very cool. Have a friend, near Boston, who has an early TBF in his garage and who restores gun turrets and hemi mopars. We have recently acquired, from Pensacola, a FM-2 Wildcat out of Lake Michigan and a SBD-4 out of the jungles on New Guinea which flew off the original Enterprise. Our operational F-14 was flown in 3 years ago along with A-4TJ Aggressor Squadron Skyhawk. Our F4J Fury is almost ready for paint thanks to the help from the Navy at Fallon in the restoration process. Currently awaiting delivery of our operational F-18 and the last F-4N to make a carrier landing which is also fully complete. Several other jets, plane and helos also on board the hanger deck. Working on these machines is a blast, isn't it?

 

SBD-4 Huh?. . . . .
Where I'm at is/ was an SBD training facility 42-46 and all that fell fron the sky here are long gone "war stories". Between the native tannens, post war "Agri-Chemicals & high ambient temps of shallow lakes & bogs hardly anything at all is recoverable, altho USN charted all grounding sites, they're now little more than depressions in the earth.
The CAF Dixie Wing in Peach Tree City, GA is flying a SBD-5. In fact we had it here two years ago during an event.It lost it's upgraded 1832 CW Radial & we had to ship it back via the Interstate on one of Mitchells Trucks. Now there's a story for a warbird! They have videos etc on their website of it. Glad to meet another airdale here on FTE.

CIAO FBp