Ol John Lee's gettin a break system safety upgrade and long overdue overhaul

[jonathan-m]

I'm in the same boat as you today Sharps, I had to replace my Master cylinder today and I've been trying to bench bleed it and get a good pedal out of it. Unfortunately mine isn't going as well as yours. Found out the first MC I installed was bad, replaced that one and now I still can't get a good pedal to save my life. Plus bleeding brakes on your own is a royal pain. If I never in my life had to mess with a brake system I'd be a happy man. Sad thing is I can't even drive it down the road to let a brake shop do the job for me hahaha.

[Sharps40]

Break for the night. Rear seems right. Still a bit of air RF. But solid 1/2 pedal. Mostly spent 4 hours on wife to get done w/all the mother in law crisis- no pepsi-nochips-3rd trip was no pretzels. I think I'll get check valve bleeders. Only hiccups were a leeky LF bleeder screw (one of the old ones I could get a wrench on). But put the new one back in and fiddeled up a wrench to fit and it sealed up and I finally blew out the air. Lettin it set over night and will bleed it 40eleven more times. A good adjust on the shoes should bring the pedal to 3/4 or more.
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[Sharps40]

Originally Posted by jonathan-m

I'm in the same boat as you today Sharps, I had to replace my Master cylinder today and I've been trying to bench bleed it and get a good pedal out of it. Unfortunately mine isn't going as well as yours. Found out the first MC I installed was bad, replaced that one and now I still can't get a good pedal to save my life. Plus bleeding brakes on your own is a royal pain. If I never in my life had to mess with a brake system I'd be a happy man. Sad thing is I can't even drive it down the road to let a brake shop do the job for me hahaha.

Yeah breaks are tough. I think this is the most difficult job on Ol John Lee yet. But almost done. Keep at it, I had to get jiggy with the master to force air out of the lines. The one I have took a lot to bench bleed. Finally put it on the truck since it was leveled on the jack stands and burped it a bit with the pedal and the resevour lines alternatly cracked up at the master body to get that last bit of air out of the primary resevour. I have some more bleeding and shoe adjusting to do today but hopefully I'll be done in time for a sunshiney ride.

[Sharps40]

Finally done with the brake redo and upgrade. 25 mile test ride with no leaks and no flaws. Brakes work the same now as with the old single resevour master but with the piece of mind of a redundant system. No one leak can cause the failure of all four wheel cylinders. Pedal, just like the old single system, starts gripping drums at or near 1/3 stroke and is rock hard just at 1/2 pedal. No more stuck wheel cylinder acting as a hill holder, let go of the pedal and the truck rolls. I'll prolly blead it again after some riding but we flushed 48 oz of fluid thru all the new lines chasin air bubbles. I suspect the front system needs blead a bit more. Lettin it all sit over night last night helped a lot, we left with 4 solid streams from the bleeders but came back to some air bubbles in the front this morning. So a reblead or two won't hurt. Had troubles with the new LF wheel cylinder, the bleed screw just would not seal, tried three others w/o luck. Fortunatly Orellies had another cylinder on the shelf and 10 minutes to swap it and rehook the hose and I was finally totally leak free.

So, here's the final tour and photos of the part numbers not yet included in the thread.

The new dual resevour drum/drum non power master....pretty much a direct swap for the old single resevour master. This is an Al Cardone rebuild, $15 bucks.



Here are the two main feed lines runnin down to the frame. Both lines are 1/4 OD Poly Armor lines held against rattlin by romex clips. I'll add an insulator down by the rams horn later....thats the factory location for the brake line but a wrap of brass for now and I'll add a heat shield another day.



The LF wheel assembly, shot of the new hose. Didn't realize how ugly the original hoses were till I saw these spanky new ones in the box...sure looks good on Ol John Lee



At the LF frame rail, the T fitting accepts the 1/4 drop line from the resevour closest to the fire wall and branches off to feed the LF and RF wheel cylinders thru their respective hoses. As stated above, I used a longer hard line from the T fitting to the RF hose to eliminate the RF T fitting and the RF hard line between RF t fitting and RF hose. The other single line you see is the second 1/4 drop line from the resevour farthest from the firewall. It is a direct feed across the crossmember to the right frame rail (where the old RF T fitting used to be) and carries fluid back to the 3/16 lines for the rear cylinders.



Heres a shot of the RF assembly, again, a new hose running from new lines to the new wheel cylinder. The fit for the bleeder screw is close, if I need to work this side again, I'll be sure to grind a bit of clearance on the spindle so a thin wall socket will fit the bleeder screw. Useing an open end wrench ain't the best on these soft metal screws.



Where you see the romex clip on the cross member is where the RF t fitting used to be. The romex clip secures the 1/4 line that feeds the RF wheel cylinder. The other line is the second 1/4 drop that turns rearward to eventually mate up with the rear 3/16 hard lines.

[Sharps40]

Here at the RR is the ending of the 1/4 hard lines I ran to feed the rear. The end of the 1/4 hard line mates to the 3/16 adapter line...(a special 8" long section of 3/16 hard line with a 1/4 fitting on one end and a 3/16 fiting on the other end to screw into the factory repacement hose). The hose comes off the adapter and into the RR t fitting which branches off 2 3/16 lines to the rear wheel cylinders.



Here is the new 3/16 line from the RR t fitting feeting the new RR wheel cylinder. Factory clips on the axle houseing didn't break off which was a suprize...so the routing is about the same as factory and no fancy giant hose clamps needed to hold the line still.

[Sharps40]

Prolly the least pretty line I had to install. But no flareing tool or skill for that matter so I used a line just a bit too long to fit from the RR t fitting to the new LR wheel cylinder. I made sure that the frame bumper, panhard bar and exhaust had plenty of room so the line won't hit them. In any event, the turn up is lower than the top of the punkin so all in all, not too bad for a daily driver.



Yesssss, I know, I gotta lotta cleaning to do under there but it sure was fun makin a mess squirtin oil all over the place and break fluid is a darn good greese and grime remover so the axle and the backing plates and even the front control arms and spindles are quite a bit cleaner now for all the drips! I caught mosta the mess in the oil drain pan and on big rags positioned under and around each work surface.

[Sharps40]

This is the master cylinder used. I forgot to photo the part number previously for those that asked.



To mate the new master to the new 1/4 hard lines, I used one each of the adapters shown on the left and middle. To make connections of the 1/4 lines running across and back I purchased and used 4 of the 1/4 unions shown on the right.



Other than some driving and I am sure a rebleed or two and most likely some final tweeking of the shoe/drum clearances, this brake upgrade is done and should be good to hook for many miles to come. Lotsa confidence now. Short of confirmation, I've completed the full accounting of repairs I wanted for Ol John Lee as a daily driver in 2012. The rolling stock is all new, the power pack seems to be in good shape for 49 years old and the body, ahhh, that sexy blue body....what can I say, Perfect!

[Sharps40]

Another short ride this morning. Everything working as expected, good brakes and it stops even. No leaks anywhere in the breaking system. So with this job nearing the final tweeking phase (shoe adjustments and some final bleeding just to be sure all the air is out) I'll have to call it a success.

When I adjust the shoes again this week I'll pull the drums and check the wheel cylinders for weeping around the pistons and report back but I'm not expecting any issues

A big THANKS to my friend for loan of the heavy duty 3/4" drive tools to yank and reinstall the brake system out and thanks to Orellies for keeping parts in stock for a 49 year old truck!

[Sharps40]

Drove it around tonight and bought GoodWife Sharps dinner so she volunteered to pump the brakes again. It felt a bit soft in the top end so, home and 4 good squirts out the rear, no bubbles or burps so I think the system from master to rear is just fine.

Did the front again and even though it was solid streams of fluid last night, had some froth and burps from the RF again, so, was still a bit of air in that one. LF was a solid stream of fluid. Did a quick pedal check and yep, a good bit firmer in the top end of the stroke so, feeling good about the return trip to work tomorrow and another bleed or three should have it licked for the long haul.

[Sharps40]

Pretty much reached the point of calling the brake job done.

The initial ride after install had a rock hard half pedal with sponge on the top end, the air was in the RF cylinder, blead it and it worked fine. Also, the shoes were adjusted up tight at that time, drag set to stop the tire rotateing freely about about half to three quarters spin of the tire. As the shoes and cylinders centered up, the top half of the stroke got slow to engage but not spongy so I knew I needed a final tweek of the shoe position to max the pedal.

Did that today....went around all four for one more bleed and all was well. Topped off the master and pulled each drum checking for leaks. There are no leaks and no weeping of the cylinders so the system is right and whether or not there are checkvalves in the rebuilt cylinder (there was some discussion of this issue), I'm pretty well satisfied at 500 miles that its all in right and working properly. In any event, the rebuilt master had the brass check valve fittings installed and wouldn't pass a toothpick into the bore, so I spect the valves are in there.

RR no leaks, just pulled up the shoes closer to the drum and buttoned it up till the next set of shoes are needed.





LR, same, no leaks, a final adjustment and buttoned up.



RF, dry and only in need of final shoe adjustment. Also buttoned up for a while yet.



And last but not least, the LF, dry, adjusted and buttoned up.



So, a test drive this afternoon and a quick engagement of the brakes at the top 1/4 of the stroke followed by more than half pedal rock hard. No sponge, no push back through the pedal from the cylinders and I'm well pleased to have more modern and safer brakes on the truck.

Time to start savin for an engine. So which should it be for transmissions,,,,Muncie M20 or a good old TH350 so even my wife can drive it?

[geezer#99]

Put the m20 in it and teach her how to speed shift. LOL!!
Did you put a little smear of grease on the tabs the shoes sit on on the backing plate?

[Sharps40]

Originally Posted by geezer#99

Put the m20 in it and teach her how to speed shift. LOL!!
Did you put a little smear of grease on the tabs the shoes sit on on the backing plate?

She can shift, but we're both gettin lazy and really like the automatics in the sebring and the ford van.

No grease on the backin plate, never heard of that before.

[geezer#99]

Grease keeps them from sticking and chattering. I saw that in a tech tip somewhere and have done it since. Won't hurt if you don't have it.

[Sharps40]

Huh, thanks for a new tip!

[lolife99]

Great thread.
Too bad most of the images were lost.

[Sharps40]

I know, but the bulk of the lost photos didn't deal with the actual split out ... just the adjustment of shoes, bleeding etc.

But after the destruction of Ol John Lee, we had to do the same with John Lee Jr his replacment. So, see the attached thread starting at Post 207 for more on brakes split and upgrade. Prolly some carb work mixed in there too. Seems I was doing door seals, carb tuneing and brakes all at once.

http://67-72chevytrucks.com/vboard/s...=571916&page=9

[Sharps40]

By way of an update on the Small Miti Vac I bought ($50 at Oreilly Auto)....

Its in the trash.

I found it useless for bleeding break cylinders, both with the system totally dry (insufficient size to easily pull out all the air from long lengths of new line) and the fit of bleeded screws allows in too much air to vacuum out the last air bubbles from nearly blead wheel cylinders.) Gravity feed and lots of pedal pumping worked best for me on the latest brake overahul.

In addition, when useing it to determine that my 63 Chevy II has a plugged fuel line, it broke. (Second project). The seals went bad, started sticking and no amount of cleaning or lube of the vacuum chamber would free it up for proper function.

My assessment is its basic junk, I'd rather have a vacuum gun set up for an air compresser to pull fluids.

I did find it useful for checking Dizzy vacuum can function but that don't merit a $50 investment...$6 for a new can would have been a better investment.