Bought a bus - info wanted!

dalez · 12-03-2014, 09:52 PM

Hello! Finally bought a partial conversion - 84 international s1853 with dt466 and allison mt643! Engine runs great, transmission shifts fine, although I'm gearing limited to 55-60mph currently. But the hydroboost brake backup motor appears to be dead, victim of a leaking master cylinder drip through the electrical feed bushing into the motor. I'd replace the whole cylinder/booster/motor assembly, but I cant seem to find one! At least not online, I havent taken it to Napa yet. I cant seem to find a service manual for this bus either, any enlightenment to be had here?

EastCoastCB · 12-04-2014, 06:29 AM

Have you tried Midwest? I have the same running gear as you and am looking for a manual as well.

dalez · 12-04-2014, 12:10 PM

Midwest-autoparts.com? They only go back to '85 international trucks and they dont have one for that year either. =\

Does anyone know how to adjust the parking brake? It sucks having to have 2 people to go anyone since even on level ground the bus wants to roll away before you chock it...

Booyah45828 · 12-04-2014, 01:49 PM

You have a picture of the brake master cylinder setup? I have manuals for s series 83-85 trucks so I might be of some help. Also there are different types of park brake systems used on these rigs as well so you'll have to give me a clue as to which one you have in order to give you adjustment procedure.

EastCoastCB · 12-04-2014, 02:56 PM

Check Ebay.
And Carquest.

dalez · 12-04-2014, 04:42 PM

claydbal · 12-05-2014, 06:57 AM

dont know if it helps, but i found my brake calipers at oreiily. dirrect replacement oem rebuilds!

dond · 12-05-2014, 09:25 AM

Here's some stuff found on the 'net. Maybe some of it will be helpful.

http://precisionrebuilders.com/pdf_cata ... B-0398.pdf
http://shop.industrialbrakeandclutch.co ... 980565.htm
http://www.powerbrakeservice.net/noname.html

Booyah45828 · 12-08-2014, 10:48 AM

The above is a completely different system. What you have is the Hy-Power booster system which was made by Delco. Part # 504837C91 is for the booster. Part # 18006974 is for the motor. I can't find an entire assembly number but those two should help you get what you need.

That motor is only used as back up to the hydroboost so I'm not sure how you figured out that it wasn't working, but according to the manual, the emergency pump will only put out 800 psi brake line pressure vs 2000 psi brake line pressure when system is operating normally.

Now for your park brake. There is a lever on your brake assembly that will be on the bottom half of the assembly. I circled it in your picture here.

That lever operates the s cam inside the brake which expands the shoes. At the other end of the lever, which is out of view of the picture,there should be a clevis on the threaded end of your parking brake cable. That clevis is where you adjust it. Take a picture on the other side if you can and one of the apply handle inside the bus because you might actually adjust it from the inside.

jazty · 12-08-2014, 12:39 PM

Quote:

Originally Posted by Booyah45828

That motor is only used as back up to the hydroboost so I'm not sure how you figured out that it wasn't working, but according to the manual, the emergency pump will only put out 800 psi brake line pressure vs 2000 psi brake line pressure when system is operating normally.

Mine operates when the ignition is on, but the engine isn't running. My guess is that it has a pressure sensor.

dalez · 12-08-2014, 01:58 PM

There is a sticker that says if you don't hear the motor running when ignition is off and brakes are applied do not drive. On the other international I test drove it was really obvious when the motor was on, the pedal would buck. We tried applying voltage directly to the motor and nothing happened.

Booyah45828 · 12-08-2014, 03:01 PM

Yes, there is a flow switch in the system that will provide power to the electric motor when flow from the powersteering pump isn't present. I don't think I've ever worked on or have even seen one, most are usually air brakes. I didn't know about the sticker and was curious as to how you tested for operation.

dalez · 12-08-2014, 10:10 PM

So we tightened the adjustment at the clevis on the drum end of the cable to it's fullest, and found the tightening knob on the parking brake lever and maxxed it out. The lever feels a little tighter now, and the bus actually holds on somewhat level ground now, but it's FAR from proper holding torque. Anyone know how thick the shoes should be? It's either they're too worn down or my cable stretched I assume...

Booyah45828 · 12-09-2014, 09:02 AM

I'd say your cable is stretched. There should be enough adjustment there in order to make worn out lining hold. The only thing I found regarding thickness was this. "if linings are worn too near rivet heads, or are otherwise damaged, punch out old rivets and remove linings from brake shoes." In all honesty, linings should never wear out because they shouldn't be used to stop the bus, just to hold it. So if they are wore out it's because someone moved it with it still engaged.

dalez · 03-13-2015, 10:35 AM

Hello again! Booyah thanks for those part#'s on the booster pump and booster, it's made locating parts much easier!

Does anyone just happen to have any diagrams or info on disassembling the parking brake so I can check the shoes/hardware? Also any info that makes identifying which calipers my bus has is appreciated!

Booyah45828 · 03-15-2015, 08:26 PM

Yeah I'll look it up tomorrow for you. I have about the same exact bus as you('84 1753) with the service manuals to go with it. You have the desirable engine and trans but I for the life of me cant understand why you don't have air brakes. I thought it would have been standard on the heavier bus.

EastCoastCB · 03-16-2015, 01:20 AM

Some districts don't even allow air brakes and spec only hydraulic.

nat_ster · 03-16-2015, 08:56 AM

Quote:

Originally Posted by EastCoastCB

Some districts don't even allow air brakes and spec only hydraulic.

Due to lack of qualified drivers. Same with the auto transmissions.

Nat

Booyah45828 · 03-17-2015, 08:24 PM

Here are the pages you asked for. I'm going to link them versus embed because they are huge. http://i816.photobucket.com/albums/z...psteudagjs.jpg
You wouldn't happen to have a tach on your bus would you?

Outcast · 03-18-2015, 01:55 PM

Quote:

Originally Posted by nat_ster

Due to lack of qualified drivers. Same with the auto transmissions.

Nat

I was told that my 96 Amtran was spec'ed for hydraulic brakes because the state/county that ordered it is in the cold northern states. They didn't like dealing with the issues of water build up in the air lines freezing the systems up, so they only use hydraulic systems.

You may also like: