Broken rear pinion

[subzali]

I will be working on it Saturday night, not sure exactly what time but probably after 7 or so. If you don't mind the drive to Sedalia (~1/2 hour from Hampden/285 and either Santa Fe or I-25 (take your choice)) and standing in the cold barn (I do have a space heater though), then anybody is welcome to come. PM me for directions/address. My plan is to center the steering knuckles (I have to get the tool back to TJ). If that goes quickly then the axle reassembly can start.

 

[timmbuck2]

if I get the engine out and also get some kitchen work done, I will be there. PM me directions.

T

 

[subzali]

Pulled a 7pm-3:30am Saturday night - got my knuckles centered, the passenger side was way off, got my front axles back in, front driveshaft on, flipped my rear driveshaft around, then moved some people all day Sunday, then went up to Fort Collins to check out TJ's 40 and get the tool back to him, then came back to Denver to pick up some furniture from my aunt. I'm nuts

Then Monday night went down again, filled up the front and rear diffs (85-140 for the Lockright in the rear sucks when it's this cold), bled the brakes and went to town to get some gas. Everything was hot - the rear brakes were dragging and the front hubs were hot (the brakes might have been dragging, don't know). Got home and adjusted the rear brakes out and loosened the wheel bearings a smidge, but the brakes are still weird. When I first pushed them in, the pedal went down a long way, but then pumped up. Then I went a little further and the pedal was RIGHT THERE and the rears locked up. So I'm going to check that the return springs didn't fall off or something weird, then re-bleed them all.

Stupid question - This is a dual circuit master cylinder, so if you lose pressure on one circuit (like the rears like I did when I replaced the cylinders), do you still have the bleed the fronts or should they be okay? I have to bleed the whole system anyway, but I was just curious. I guess it doesn't take that much longer to do, so you might as well do it, but still...

 

[treerootCO]

Yes you need to bleed the brakes front and rear. Start from the furthest point from the master and work in from there. I am not sure where the thought that a dual circuit master works independently from each other. When I lost my front brakes at the Caravan For Kids, I lost my bakes completely. The master is one cylinder and if one circuit goes out, the fluid from the other drains out as well. Any air in either circuit affects the other because without hydraulic pressure, the air can be compressed and the pedal goes to the floor. I am getting fairly confident in adjusting drum brakes to the point that they work just as well as disc brakes (when not wet or dirty).

http://forum.ih8mud.com/40-55-series-tech/32848-troubleshooting-brake-problem.html

post #28 more or less...

 

[MDH33]

... This is a dual circuit master cylinder, so if you lose pressure on one circuit (like the rears like I did when I replaced the cylinders), do you still have the bleed the fronts or should they be okay?[/b] I have to bleed the whole system anyway, but I was just curious. I guess it doesn't take that much longer to do, so you might as well do it, but still...

You should probably disconnect both circuits and bench bleed the Master Cylinder before you start bleeding the system. That could be the reason you had to double pump. This will give you a chance to run some new fluid through your whole system as well.

 

[subzali]

Cool. My brakes have always worked really well up to now (like Treeroot my rears stop as well as my front discs), so I've never had to deal with problems, but I figured that's about all there was to it.

 

[Rzeppa]

Stupid question - This is a dual circuit master cylinder, so if you lose pressure on one circuit (like the rears like I did when I replaced the cylinders), do you still have the bleed the fronts or should they be okay? I have to bleed the whole system anyway, but I was just curious. I guess it doesn't take that much longer to do, so you might as well do it, but still...

No, you don't, but you may as well. Normally, by the time you have some kind of work to do on one end, the other end's fluid is dark and yucky and should be replaced by now.

There should be no need to bench bleed the master unless air got inside it somehow. The air you get in the lines from doing cylinders and calipers doesn't usually go all the way back to the M/C unless you don't cap off the lines while you're working and draw air in through the reservoir at the M/C.

Mike, there may be something wrong with your M/C. I have had one end go out and the other end continue to work (many years ago on my 76 FJ40) and more recently on my daughter's 85 runner. The front and rear circuits are supposed to be independent of each other, other than they are mechanically actuated by the same rod.

Having to double pump is caused by wheel cylinders being adjusted too loose. Air in the system causes sponginess, but does not have anything to do with double pumping.

 

[subzali]

Well, it was my brakes, the problem was that I replaced the booster at the same time and didn't give the pedal any freeplay when I put it in, so the master cylinder was slightly on all the time. I loosened up the nut to give it some freeplay and it's fine now.

But what I was really wanting to do is update this thread with part numbers that some might find useful if they end up setting up their own diffs. Charlie Glabe's Writeup is a great resource, once you get used to all the terminology, so that's what I will try to help with. BTW - make or find someone who has the side adjuster tool - you will be stopped dead in the water without it. I just wanted to say a few things and answer a few questions that I had to spend time wondering about, so don't make fun of me for being stupid . BTW, all this stuff comes in a diff setup kit, but this is for the people who decide they want to go through Toyota and build a kit piecemeal.

Pinion depth shims - this guy comes out when you pound out the inner pinion bearing race. It's about three inches in diameter, and its purpose is to set the pinion depth so that the tooth pattern on the ring gear is okay. They come in five different sizes from Toyota, you need to (by trial and error) find the correct one for your ring, pinion, and housing setup.

Toyota calls them "Shims":
90564-68001 - 0.25mm (0.0098")
90564-68002 - 0.30mm (0.0118")
90564-68003 - 0.35mm (0.0138")
90564-68004 - 0.40mm (0.0157")
90564-68005 - 0.45mm (0.0177")

For example, a 0.40mm shim came out when I pressed out the race. As I'm setting up my gears, I will again use a 0.40mm shim. If the tooth pattern is not right, then I will have to pound out the race again and REPLACE the 0.40mm shim with a different shim - you DO NOT stack shims unless you are very unlucky.

Next are the Preload Washers - These have a thickness to them and a beveled edge that sits against the shoulder on the pinion, and they are the fine tuning adjustment of the preload. You only use one.

Toyota calls them "Spacers":
90560-30184 - 2.74mm-2.76mm (0.108"-0.109")
90560-30185 - 2.77mm-2.79mm (0.109"-0.110")
90560-30186 - 2.80mm-2.82mm (0.110"-0.111")
90560-30187 - 2.83mm-2.85mm (0.111"-0.112")
90560-30188 - 2.86mm-2.88mm (0.113"-0.113")
90560-30190 - 2.89mm-2.91mm (0.114"-0.115")
90560-30191 - 2.92mm-2.94mm (0.115"-0.116")
90560-30192 - 2.95mm-2.97mm (0.016"-0.017")
90560-30199 - 2.98mm-3.00mm (0.017"-0.018")

Finally, the Preload Shims - These work in conjunction with the Preload Washers, and get you close while you dial it in with the Preload Washers. They come in one size only, and you can use up to four (4) if needed.

Toyota calls them "Shims":
90564-30035 - 0.25mm (0.010")

So for the whole kit, you will need to get one (1) each of the five (5) Pinion Depth Shims, one (1) each of the nine (9) Pinion Preload Washers, and four (4) of the Pinion Preload Shims.

HTH for anyone interested...