Factory Brake Job

[Barry Maxwell]

5-66-1 is only used on 1 ton and larger trucks which use a banjo bolt to hold the connector in place. It is not used on B or C series trucks. See page 5-15 of the part book, note the connector is only used in the illustration for 3-4 ton trucks. I have seen two types used on the B & C series trucks: one where a SAE 45 degree fitting is machined into the wheel cylinder or a pipe thread is machined in and you screw in a brass or bronze fitting with pipe thread on one end and a female SAE 45 on the other end to accept the brake line SAE male fitting.

P15-D24:

Boy, am I confused now! It wouldn't be the first time. I see connector 5-66-1 on page 5-15, but that is not the cylinder I have on both rear brakes. The cylinder I have is shown on page 5-4 and the connector is also 5-66-1. Perhaps I have one of the types you have seen on B series trucks where the double flare female fitting screws into the cylinder and is sealed with the copper washer. What am I missing?

Barry (confused in PA)

[P15-D24]

P15-D24:

 Perhaps I have one of the types you have seen on B series trucks where the double flare female fitting screws into the cylinder and is sealed with the copper washer. What am I missing?

Barry (confused in PA)

I think this is correct. If you look at the actual part numbers on the page 5-36 you will see 1 tons (and larger) use a different part number than B & C trucks. On page 5-4, Plate 5-4  the item 5-66-1 looks like one of the pipe thread to SAE 45 adapters I mentioned. ( I have seen them in brass or steel)  A gasket would be correct on the pipe thread side of the connection into the wheel cylinder, but not on the SAE flare side. (In fact the brass fitting to SAE is what I have on my truck front brakes right now). Again a washer on the flare side is incorrect and will leak.  You need to inspect your wheel cylinder and determine if it has female SAE flare or pipe thread fitting, then install the correct components. The flare should have an angled seat and usually the hole is smaller than the ID of the overall hole. A pipe thread will be a straight threaded hole no angled seat.  Over the years I have seen both types as replacements types. Notice on Plate 5-3 for the front no "connectors" are mentioned so you really need to inspect your replacement parts to determine what is needed. 

 

Edit: in re-looking at the photo with the cylinder in the vice it looks like you have the correct brass flare fitting that screws in the wheel cylinder and mates with the SAE flare fitting.  Those are pipe thread so they should self seal just by tightening correctly. (I have never had one leak on the pipe thread side, it's always the flare side)  I would be careful torquing them with a hammer. ( use a torque wrench!  )

[P15-D24]

One other thing. Before you start pressure bleeding you need to clean and check for leaks at every connection and the T block where the lines split.  I clean each connection with denatured alcohol to remove any residual brake fluid and make sure they are dry. Then pressurize the system for five minutes, wait five minutes then do an inspection. I use a kleenex to touch each connection to look for any trace of brake fluid moisture. If you have any leaks you will not be able to succesfully bleed the system. The T block is susceptible to hairline cracks with a very slow leak.  If you still have not had success in pressure bleeding in 2-3 trips around the truck start looking for a leak. 

[HanksB3B]

One other thing. Before you start pressure bleeding you need to clean and check for leaks at every connection and the T block where the lines split.  I clean each connection with denatured alcohol to remove any residual brake fluid and make sure they are dry. Then pressurize the system for five minutes, wait five minutes then do an inspection. I use a kleenex to touch each connection to look for any trace of brake fluid moisture. If you have any leaks you will not be able to succesfully bleed the system. The T block is susceptible to hairline cracks with a very slow leak.  If you still have not had success in pressure bleeding in 2-3 trips around the truck start looking for a leak. 

 

Thanks Moderator,

 

Just what I needed to hear. Today I removed the two lines that that run from the "T" Block to the left and right upper brake cylinder. I found all four flanges (performed by yours truly) were single flare and it kind of triggered a memory of finalizing the brakes lines with a flatbed on the way to take the truck to the autobody shop.

 

I was able to salvage the lines by cutting the minimal off and making four new clean double flares with new flare nuts. 

 

One thing I have learned about working a new double flare into a fitting is that the first time you tighten it remember that you are first squeezing metal and deforming the flare. Seat the tube nut into the fitting then back off and then re-tighten a number of times to really get the feel for when the flare has formed to the nut and is seated. The next time you remove and reinstall it will become very obvious that the "forming" is over and it just seats tight.    

 

aah ha...here's the most likely culprit:

 

A passenger car master cylinder (they do fit our trucks and work just fine) this is certainly not the new one from Gary.  So there you have it Jeff the most likely cause of contamination to the new lines was the old master cylinder remained.

 

 

The brakes are fully assembled with the cylinders that were on the truck when I bought it. They have been rebuilt (above). I plan on loading <5 lbs pressure and testing the system tomorrow. I'm wondering if by using a band clamp I might be able to actually step on the brake pedal a bit.

 

I plan on rebuilding the newer cylinders from Gary (the ones with the skirt integral with the piston.  Gary told me today that the rear brake package is part 947580 and that it is supposed to have an integral skirt piston. Per a discussion with Gary today I learned that my rear brake cylinders are not the first set the truck came with (duh!) and the actual factory part has a split piston similar to Garys (the upper pair in post #).

 

 

That you kindly for viewing this post. I'm not sure I thanked everyone yet. What a great resource the P15-D24 Forum is.

 

Hank 

 

P.S. I also found longer bleed screws and a great 5/16" / 3/8" offset brake bleeder wrench.

Edited April 1, 2014 by HanksB3B

[Dodgeb4ya]

The aluminum piston cup expander of  the MoPar OE two piece piston shown above is the best for leak free wheel cylinders as it helps flare the rubber cup against the cylinder wall.

Those are the internals I use if I have or can get them.

 

I find these factory MoPar brake parts at swap meets and on Ebay.

Bob

Edited April 2, 2014 by Dodgeb4ya

[Jeff Balazs]

Hank;

I sure hope others who are in the re- commissioning phase of their projects are following all this. This has certainly been a good argument for a serious flush of the braking system. Good luck I hope it all works out.

 

Jeff

[HanksB3B]

The aluminum piston cup expander of  the MoPar OE two piece piston shown above is the best for leak free wheel cylinders as it helps flare the rubber cup against the cylinder wall.

Those are the internals I use if I have or can get them.

 

That's what  I would have imagined would be the case as well. I ordered rebuild kits from Gary and they should be here today. I just might pressure test the old ones that I just rebuilt and run with the newer ones from Gary and save them these as spares. The install/uninstall process doesn't take me very long now

Where are you able to get the correct kits ?

 

Hank;

I sure hope others who are in the re- commissioning phase of their projects are following all this. This has certainly been a good argument for a serious flush of the braking system. Good luck I hope it all works out.

Jeff

 

Thanks Jeff. On the other hand this thread shows good reason to do what you did and convert to disc brakes.

 

Hank 

Edited April 1, 2014 by HanksB3B

[Jeff Balazs]

Hank;

I am happy I did. The type of problems you have had to deal with on this would have driven me right over the edge.    Granted it is a short drive....but just the same I am glad to have avoided all this. Just goes to show how something relatively simple can require a fairly complex solution on these old trucks. Anybody just starting to get into one of these would do well to learn from what you have been through. There is a lot more to getting one of these done up right than meets the eye. Hopefully you have helped others to get past this potentially serious pitfall on their projects. Thanks for sharing.

 

Jeff

[Barry Maxwell]

 

Edit: in re-looking at the photo with the cylinder in the vice it looks like you have the correct brass flare fitting that screws in the wheel cylinder and mates with the SAE flare fitting.  Those are pipe thread so they should self seal just by tightening correctly. (I have never had one leak on the pipe thread side, it's always the flare side)  I would be careful torquing them with a hammer. ( use a torque wrench!  )

P15-D24:

Thank you for continuing to help me out with my problem. I really appreciate it. The SAE flare fitting I have, however, does not have a pipe thread. It has a machined thread that screws directly into the cylinder and bottoms out only when it contacts the brass washer, and that is where the seepage occurs. My cylinders are new from NAPA. I will call Gary Roberts and find out what fittings are used in his cylinders. Unfortunately, I now have a major leak in the line that connects the upper and lower cylinders. However, I can make a new line after I get the right brake line and fittings. Thank you also for your EXCELLENT tips on the bleeding process. Very helpful.

Hank:

A quick question for you if you are reading this post. Does the brass fitting on the cylinder in the vice in your post 121 have a pipe thread or a machined thread as mentioned above?

Barry

[HanksB3B]

 

Edit: in re-looking at the photo with the cylinder in the vice it looks like you have the correct brass flare fitting that screws in the wheel cylinder and mates with the SAE flare fitting.  Those are pipe thread so they should self seal just by tightening correctly. (I have never had one leak on the pipe thread side, it's always the flare side)  I would be careful torquing them with a hammer. ( use a torque wrench!  )

P15-D24:

Thank you for continuing to help me out with my problem. I really appreciate it. The SAE flare fitting I have, however, does not have a pipe thread. It has a machined thread that screws directly into the cylinder and bottoms out only when it contacts the brass washer, and that is where the seepage occurs. My cylinders are new from NAPA. I will call Gary Roberts and find out what fittings are used in his cylinders. Unfortunately, I now have a major leak in the line that connects the upper and lower cylinders. However, I can make a new line after I get the right brake line and fittings. Thank you also for your EXCELLENT tips on the bleeding process. Very helpful.

Hank:

A quick question for you if you are reading this post. Does the brass fitting on the cylinder in the vice in your post 121 have a pipe thread or a machined thread as mentioned above?

Barry

Hi Barry,

 

It took me a while to understand why Teflon tape was used on tapered fittings and not on the machine thread. It just seemed that if it was tapered it would tighten, but in that case the Teflon is not really usead truck truck to seal the connection but rather seal the connection at a particular position. I learned from an old school pipe fitter to cut Teflon back a.thread or so before installing. In your particular case I would try using Teflon tape on that particular fitting. I did polish the copper washer on a flat surface with 320 grit wet or dry paper after reading what you had to say. The flare nuts do not get Teflon because the seal occurs where the formed flare mates when with the fitting which is 7/16-20. I'm still looking to replace mine with new. If I find some do you want a pair ?

 

Hank 

[Merle Coggins]

Those fittings should be a SAE straight thread which needs a sealing washer. Teflon tape wouldn't help with these as the sealing doesn't occur on the threads.

 

Barry, if you have one that won't seal no matter what type of washer you are using, I would suspect a cracked fitting or cracked threaded bore on the cylinder. As long as the sealing surface is clean, smooth, and square to the bore, it should seal with a good copper washer. You may want to try a Dowty washer, which is like a crush washer, but it has a rubber seal around the inside.

Edited April 1, 2014 by Merle Coggins

[HanksB3B]

Those fittings should be a SAE straight thread which needs a sealing washer. Teflon tape wouldn't help with these as the sealing doesn't occur on the threads.

 

Barry, if you have one that won't seal no matter what type of washer you are using, I would suspect a cracked fitting or cracked threaded bore on the cylinder. As long as the sealing surface is clean, smooth, and square to the bore, it should seal with a good copper washer. You may want to try a Dowty washer, which is like a crush washer, but it has a rubber seal around the inside. 

 

 

In theory I agree and was thinking the same thing about cracked fitting or body. If the nut still has exposed thread and can seat deeper, maybe you can sand/flat with 320 or 400 paper to flatten the tip and create a slightly larger contact patch ? Best would be to locate new fittings (me-too)

 

O.K. back under the truck,

 

Hank 

[TodFitch]

For whatever reason, I've never had an issue with the pipe threaded portions of my braking system leak even though I've always installed them with no tape and no joint compound. Lucky I guess, but I've attributed that to the brass deforming enough to mate well and thus forming a seal.

 

But I have had issues with leakage on both water and compressed air at pipe threaded connections. And my experience has been for those that pipe joint compound did a better job for me than teflon tape. So while I do have a two rolls of teflon tape (one for natural gas and one for other stuff), I don't usually use them.

[P15-D24]

For whatever reason, I've never had an issue with the pipe threaded portions of my braking system leak even though I've always installed them with no tape and no joint compound. Lucky I guess, but I've attributed that to the brass deforming enough to mate well and thus forming a seal.

 

But I have had issues with leakage on both water and compressed air at pipe threaded connections. And my experience has been for those that pipe joint compound did a better job for me than teflon tape. So while I do have a two rolls of teflon tape (one for natural gas and one for other stuff), I don't usually use them.

Same experience as you. 

[Barry Maxwell]

Those fittings should be a SAE straight thread which needs a sealing washer. Teflon tape wouldn't help with these as the sealing doesn't occur on the threads.

 

Barry, if you have one that won't seal no matter what type of washer you are using, I would suspect a cracked fitting or cracked threaded bore on the cylinder. As long as the sealing surface is clean, smooth, and square to the bore, it should seal with a good copper washer. You may want to try a Dowty washer, which is like a crush washer, but it has a rubber seal around the inside.

Merle:

Thank you for your input on this. Right now I have two "Crush" washers installed between the fittings and the cylinders. I think (hope) they are working, but I can't tell because the line between the upper and lower cylinder on one brake developed a significant leak when I was bleeding the rears. So significant that it drained the upper cylinder into the brake drum and on to the floor and the brake bands when I rotated the drum. BUMMER! Now I have to fab a new line, probably for both rears (double bummer).

In the event that I have to go to Plan C or D (I have lost track, maybe it's E), where would I get Dowty washers? Also, even though I cleaned the brake bands with lacquer thinner, I am wondering if it will be necessary to heat the bands in the oven to get rid of the brake fluid or, worse yet, to replace them.

You just might be able tell that I am getting very frustrated with all this. Antique tractor restorations were a lot easier (no brake lines). In any event, I'm sure that this will pass in time. Thanks again for your input.

Barry

[Barry Maxwell]

Hi Barry,

 

It took me a while to understand why Teflon tape was used on tapered fittings and not on the machine thread. It just seemed that if it was tapered it would tighten, but in that case the Teflon is not really usead truck truck to seal the connection but rather seal the connection at a particular position. I learned from an old school pipe fitter to cut Teflon back a.thread or so before installing. In your particular case I would try using Teflon tape on that particular fitting. I did polish the copper washer on a flat surface with 320 grit wet or dry paper after reading what you had to say. The flare nuts do not get Teflon because the seal occurs where the formed flare mates when with the fitting which is 7/16-20. I'm still looking to replace mine with new. If I find some do you want a pair ?

Hank:

Thank you for your response. I assume that the fitting in the second photo in post 121 has a SAE straight thread and a copper washer. Correct?

I called Gary Roberts and asked him if his cylinders have straight or pipe threads. He wasn't sure but he will check. I am to call him on Fri.

Sorry to hijack your thread on this. Didn't mean to.

Barry

 

Hank 

[HanksB3B]

Barry,

I'll send you a template. That and a Hershey's Chocolate Can (why do you save these things says the wife) and you will need a quality (Eastwood) pipe bender with a small radius will do the trick, or yours will look like the one I replaced (top) 

 

I'm a strong proponent of first modeling the line in aluminium. It's way easier to form, way cheaper and give you a real good idea of which bend to make first.

 

The aluminum mock-up.

 

 

Next: light pressure bleed under observation...then overnight 

 

Here's hoping I'll get to drive this thing soon,

 

Hank 

Edited April 1, 2014 by HanksB3B

[Merle Coggins]

Barry,

You may be able to get Dowty washers at your local parts store, but you may need to visit a hydraulic hose/fitting store. They are commonly used on BSPP straight thread fittings. We also use them a lot with banjo fittings on fuel lines and etc. If you can't find them let me know what size you need. I may have something here that would work for you.

 

To clean your brake linings I'd recommend getting a couple cans of Brake Clean (I prefer CRC brand in the red cans) and spray them down and let them dry. Maybe spray them down a couple of times, just to be sure.

 

Merle

[Barry Maxwell]

Barry,

I'll send you a template. That and a Hershey's Chocolate Can (why do you save these things says the wife) and you will need a quality (Eastwood) pipe bender with a small radius will do the trick, or yours will look like the one I replaced (top) 

 

I'm a strong proponent of first modeling the line in aluminium. It's way easier to form, way cheaper and give you a real good idea of which bend to make first.

 

The aluminum mock-up.

 

 

Next: light pressure bleed under observation...then overnight 

 

Here's hoping I'll get to drive this thing soon,

 

Hank 

Hank:

I responded to your PM regarding the mock up. Thanks again. I do have the Eastwood line bender and their double flaring too.

Hi Barry,

 

It took me a while to understand why Teflon tape was used on tapered fittings and not on the machine thread. It just seemed that if it was tapered it would tighten, but in that case the Teflon is not really usead truck truck to seal the connection but rather seal the connection at a particular position. I learned from an old school pipe fitter to cut Teflon back a.thread or so before installing. In your particular case I would try using Teflon tape on that particular fitting. I did polish the copper washer on a flat surface with 320 grit wet or dry paper after reading what you had to say. The flare nuts do not get Teflon because the seal occurs where the formed flare mates when with the fitting which is 7/16-20. I'm still looking to replace mine with new. If I find some do you want a pair ?

Hank:

Thank you for your response. I assume that the fitting in the second photo in post 121 has a SAE straight thread and a copper washer. Correct?

Hank

Is my above statement regarding the SAE straight thread and washer correct? Thanks

Barry

 

Hank 

[Barry Maxwell]

Barry,

You may be able to get Dowty washers at your local parts store, but you may need to visit a hydraulic hose/fitting store. They are commonly used on BSPP straight thread fittings. We also use them a lot with banjo fittings on fuel lines and etc. If you can't find them let me know what size you need. I may have something here that would work for you.

 

To clean your brake linings I'd recommend getting a couple cans of Brake Clean (I prefer CRC brand in the red cans) and spray them down and let them dry. Maybe spray them down a couple of times, just to be sure.

 

Merle

Thanks. I will chase down Dowty washers locally. I hope I won't need them, but I have said that before. I will also buy some Brake Clean. Good idea. Thanks.

Barry

[Don Coatney]

Barry,

you will need a quality (Eastwood) pipe bender

Hank 

What makes the "quality" Eastwood bender better than the dime store version pictured below?

 

[52b3b Joe]

Those fittings should be a SAE straight thread which needs a sealing washer. Teflon tape wouldn't help with these as the sealing doesn't occur on the threads.

 

Barry, if you have one that won't seal no matter what type of washer you are using, I would suspect a cracked fitting or cracked threaded bore on the cylinder. As long as the sealing surface is clean, smooth, and square to the bore, it should seal with a good copper washer. You may want to try a Dowty washer, which is like a crush washer, but it has a rubber seal around the inside.

 

I had that same fitting on my truck leaking and I fought it for a while. I finally looked at it carefully and found a crack. I ended up replacing both sides and no problems since. I am thinking a cracked fitting could be causing it. 

[HanksB3B]

What makes the "quality" Eastwood bender better than the dime store version pictured below?

 

 

Don didn't mean it to come out that way.  Yours is just fine I wish I had one just like it. Where did you get yours ?

 

Thanks,

 

Hank   

[Don Coatney]

I don't recall where I bought the bender but Northern Tool has one just like it for fifteen bucks.

 

http://www.northerntool.com/shop/tools/product_200353976_200353976

[Barry Maxwell]

I had that same fitting on my truck leaking and I fought it for a while. I finally looked at it carefully and found a crack. I ended up replacing both sides and no problems since. I am thinking a cracked fitting could be causing it.

Joe:

I tried to replace the fittings on both sides, but NAPA couldn't find that specific fitting. Do you have a source for it? Thanks.

Barry