f3 brakes

gbs · Aug 25, 2014

need to replace brake master cylinders on our F3 they are 3/4" bore and expensive, I can find plenty of 1" bores reasonable how much difference will the 1" make as far as pedal pressure to get get decent brakes,it's a hydro machine and doesn't really need the brakes except for emergency purposes, pretty much flat country around here ,but you never now when part of a drive line might give up and leave you free wheeling,it actually runs a little to fast on the road

jm42 · Aug 26, 2014

should be able to buy a rebuild kit, I rebuilt one about 10 yrs ago, not sure they are available?

andy r · Aug 26, 2014

Are you sure it is the master cylinder???? I have a John Deere 4420 combine. Thought that it might be the master cylinder. Was always leaking out the brake fluid somewhere. Ended up being the cylinders at the brakes. Rubber cups on the cylinders had gotton bad. Bores of the cylinder were pitted. Honed the bores and put in new rubber cups along with bleeding the system and the brakes work like new. I think moisture moves downward in the brake fluid ruining the lower slave cylinders. Took sometime to get the master cylinder to pump up. Also, the hole in the bottom of the reservoir was possibly plugged stopping brake fluid from moving into the master cylinder.

Kell · Aug 26, 2014

No drum brakes on F3s, so no wheel cylinders. F3s have disk brakes like front brake systems on autos. If the master cylinder pumps and doesn't leak, it is probably good. Take a look at the calipers and pads.

And I think 1" bore MCs would work ok, might be a little grabby though.

jm42 · Aug 26, 2014

The piston in these calipers are made out of a composet material, they are known to fracture, I replaced mine with stainless I turned on the lathe, they worked perfect. I believe I had put new Orings in as well, was a long time ago. I then rebuilt the master cylinder and the system was fully functional. Did not hardly ever use them but wanted the extra safet factor.

gbs · Aug 26, 2014

one master cylinder is rusted up and the other needs a kit,i was going to replace them both but 3/4" ones are hard to find and 5 times the price of 1", if 1" would work o.k. I was going with them if the pedal effort won't be a lot different,this machine has chrome steel pistons in the calipers and new brake pads

jm42 · Aug 27, 2014

just curious, is this a 1983 f3 that was purchased in ohio? When you mentioned chrome pistons they would look like the stainless ones I had made, I sold that combine about 6 years ago to a guy in michigan, just curious.

gbs · Aug 27, 2014

found a calculator for brakes, by going from 3/4" to 1" it would take 77 percent more pressure applied to the pedal to get the same line pressure,i knew there would be a difference but not that much,this machine was bought in n.c.it's a late 1981, thanks for the replies

Tim(nj) · Aug 29, 2014

I might be mistaken, but they didn't make F3 combines until 1983. 1981 would still be an F2 . . . could be a Golden Harvest F2 which is 'almost' an F3.

f3 brakes

gbs

Member

jm42

Member

andy r

Member

Kell

Member

jm42

Member

gbs

Member

jm42

Member

gbs

Member

Tim(nj)

Well-known Member

Similar threads