F6640 No Brakes !!!

[Jackfr]

My Friend while helping us went to use the tractor and while heading out of barn down hill found that he had no brakes!! Nice!! He was smart enough to leave it in gear and coast into one of our lower fields missing some trees. I quess he never drove anything without brakes before.
The Brake fluid reservoir was empty so I asked if the warning light/buzzer was sounding when he started it. His reply was no. Funny when I jumped in to check it it was sounding loud and clear oh well you can't complain about free help as long as no one gets hurt.
We filled the system up with that special brake fluid and bled it(mostly the left system was air bound). Brakes work fine now. My question is where did the fluid go to?? There are no leaks on either brake line or master cylinders. The tractor had been sitting for about 2 weeks. It is parked inside on concrete and no wet spots under it. It appears from what I see that the clutch master cylinder is also attached to the same reservoir and there appears to be a wet area under it on the floor in the cab. RickB does this seem feasible to you that the clutch master cylinder could have emptied the reservoir? Or should I start thinking of pulling apart the left axle to check the brake cylinder. Is the Clutch master cylinder rebuildable or should I am I better off just ordering a new one? Does anyone know of a compatible brake fluid I might get locally instead of the special stuff from NH?? It's rather expensive and by the time you add shipping it's upwards to $20 a quart. I know I can't use regular brake fluid.

Jack

 

[yooper1]

I had a similar problem with my pickup truck

One day I was headed down my drive and hit the brakes at he street and the pedal went to the floor. I was able to stop and I then backed up slowly back to the garage.

I checked the master cylinder resevoir and it was about 90% empty.

I filled it up and tried the brakes and they were back up.

This lasted for about 3 weeks

Sometime in the 3rd week, the pedal went to the floor again and I again filled up the res., tried the brakes and they went down again.

I crawled around looking for visible leaks, but I could not find any signs.

I got it to my friends shop, put it up on the hoist and found the brake line running along the frame just above the rear drivers side axle was leaking. When you stepped on the pedal, it sprayed fluid up onto the frame and the bottom of the truck bed, not down where I could see it.

Anyways, it was rusted thru where a factory clamp held it to the frame. THe same place mud and grit would pile up and never be seen.

A new line and a lot of cussing and scraped knuckles got it fixed


so, I would check all the lines extremely well and maybe even 2 or 3 times first before spending big bucks on master cylinders and stuff.