Brakes...and overdrives

[Dubv1980]

Two completely seperate issues but I'll throw them in the same post!
First off, '73 Series III 88". After having a wheel cylinder go on my brakes and then being unable to get things satisfactorily bled with a firm pedal I'm here for ideas. This is also after I have had the truck at a shop that is at least fairly familiar with Series trucks to work on things as well. I have all good wheel cylinders, I have replaced the master cylinder, there are new drums and shoes all around. When I step on the brakes I get some response, but its almost as if I'm only getting about 50 percent braking power. I know on my MG there is a little valve that will close off one axle's brakes in the event a line breaks...is there a similar valve on Series trucks that I'm just not seeing..its almost as if it might be stuck closed if such a thing is in there. In addition to the sort of "half power" the pedal also is not quite as firm as I'd like...it takes one pump to get it to get a good feel. Both the shop and I have seperately bled the entire system repeatedly...and things seem to stay the same. Any ideas? There are no visible cracks/leaks on the flex or hard lines.

As far as the over drive goes, a more simple question, are replacement/rebuild parts available for the Fairey overdrive? Mine has gotten very noisey (more so than it is normally!) and I'm guessing its going to need at the very least some bearings replaced.

Thank you all in advance..my first post here in years!

[o2batsea]

Be sure that you have the shoes on properly. If you mix up the leading and trailing shoes you will have a hard time getting good pedal.
Stephen Peters at Safari HP in Orlando has Fairey parts. Bearings tho are readily available, you just cross reference the bearing number and you'll find equivalents.

[SafeAirOne]

Make sure the brakes are properly adjusted, so you're not taking up all the pedal travel just getting the shoes closer to the drums.

PDWA valve. Some rovers had them, some didn't: Good info here: http://gunsandrovers.com/showthread.php?t=1379

[o2batsea]

Yes adjust the shoes so that there is quite a bit of drag when you attempt to rotate the wheel by hand. Not locked, just one notch below that. The shoes will quickly bed and the drag will go away in a few days. The amount of travel the shoes need is literally a few hundredths of an inch.

[Dubv1980]

Thank you all! I've got the brakes adjusted so they are dragging, I could try to tighten them some more I suppose. The leading and trailing shoe is a good point. Probably bears having a look at that. Good info on the overdrive parts as well.

[slowmo]

Also, verify that one end of the top spring is attached to the backing plate. If the top spring is attached to both shoes, this is what you get. I spent a weekend bleeding and re-bleeding my brakes on this education. Once I properly attached the springs, all was good.

[Dubv1980]

Does anyone have a good picture of the leading vs. trailing shoe? Since they all got replaced I'm not going to be able to compare to how they are installed now.

[slowmo]

The post on the backing plate is fairly obvious. If the top spring is attached to both shoes, disconnect the spring which is closest to the post and attach it to the post.

By having the spring attached to both shoes, the throw of the slave cylinder is insufficient to expand the shoes against the drum, so you have to pump it up a couple of times. When you release the spring pulls the slave cylinder back where it was and the next time you apply the brakes, you have to pump it up again. Feels just like air in the system, but it isn't (unless you have air in the system).

[TravelinLight]

This may help some

http://www.expeditionlandrover.info/...rearbrakes.htm

[slowmo]

The pegs are such that there is only one way to put the shoes on with a peg against the adjuster cam.