Bolt size confusion and stuck master cylinder

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R8rPhan

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Booster problem solved..

Went and tried to blow into the PB line to the check valve.. Blocked (as it's supposed to be).. Took out the check valve end from the booster and blew that direction.. Blocked too! Went and got the new check valve I'd bought for the other booster and blew in it from each direction, it showed good..

Removed the check valve that came with the new booster from the vacuum line and blew in it, and it checked good too.. Now I'm like WTF?

The vacuum line itself was blocked... Took it in the shop and put some compressed air into it, and a bunch of hair and spider carcass came out.. Freakin' spiders! They get into everything here...

So took it back out to the truck, hooked it all up into the PCV port at the front of the carb, and presto! I have power brakes!

:banana-mario::badger_1::baby::bleh::p:005::dancingpoop::dogpile::favorites13::favorites37::favorites37::favorites37:

Gonna temp it into something (might try the line to the heater controls again) until I can find out what fitting I need and get one to hook it up properly to the rear of the carb..

So the old booster was probably good too.. But that's okay, not I have parts that are actually made and sized for the specific truck.. and the MC is brand new so there's an extra measure of security there too..

I've only tried moving the truck a few feet, but now with the super responsive brakes, it does still pull to the right.. I'll take it out for a test drive to see how bad/urgent this issue is, and now I will for dam sure replace the calipers next month.. Might replace the prop valve too, just for good measure...

Man, this thing stops freakin' good now.. Almost no foot pressure required, and easy to hold stationary in drive...

Anyone know what size that fitting is?
Google ain't helping much..

Might pull it out (probably have to do it by feel-a-vision) and see if it has the same threads as some of the various fittings I have laying around...
 

R8rPhan

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Teeing into the heater line works fine for now.. Thing stops on a dime.. The pulling isn't bad at all, but I'll work on it in the coming weeks and get rid of it.. Total cost on the brake repair so far is about $165, and that includes upgrading to power brakes..

Truck warms up quickly and stays at temp now with the new t-stat.. New turn signal indicators work awesome...

Only major issue left is the oil leak at the front crank seal.. I'll deal with that sometime in the coming weeks too..

Other than that, I have to install a windshield washer system and lines, and do something about getting intermittent wipers going..

'THEN' I can start on comfort and looks! Bucket seats, new flooring, stereo, front clip, decide what I want to do with the bed (considering going to flat/stake bed), get some bigger tires (considering larger BFG T/A radials), maybe limited slip rear end..

This thing has the 307 (or is it 305?) in it... and I was reading that the reason nobody likes that size SBC is because chevy put non hardened cams in them, causing the lobes to wear down fast and performance/mileage falls off a clif, so I might replace the cam/lifters, and timing chain with quality aftermarket ones this summer, so I can get more power and efficiency..

Still kicking around the idea of putting that 700R4 I got and the later model steering column in too, as well as a TBI system... All that would probably near double my mileage..

Feels good to have transpo again.. Between the monster snow storms, continual rain, power outages and the lack of truck, this winter has been a bear..

But it's a gorgeous day, all the snow is melted off the roads, I have reliable transpo again, and I'm a happy camper! Time to go clean up and put all the tools away...

Might even do the first campfire of the year this afternoon.. Front fire pit is dry and all the snow around it is melted off..

:big_banana_Dance:

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crpntr78

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Pretty sure sure the compressor hose fitting will work in the plug. Especially if your hose is 3/8".
 

Blue Ox

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Nice to see things finally coming together. Congrats.
 

R8rPhan

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Pretty sure sure the compressor hose fitting will work in the plug. Especially if your hose is 3/8".

It's the standard Air Compressor stuff.. I know where several are.. thanks!
 

Rusty Nail

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Lots of people read this board dude, all different kinds of folks from all across the globe..

Since you are still pulling , it's probably a good idea to remove that caliper and sand the mating surfaces of the caliper bracket with emery cloth or similar.
Those flat surfaces should be lightly greased in addition to the caliper bolts. Examine them closely to ensure one hasn't developed a "rut" = from lack of grease that CAN cause a sticking caliper, resulting in a pull because the caliper is meant to "slide" aceoss all of those surfaces... At least four per side. That action must remain fluid or it'll hang up and pull.
Doubtful the General intended caliper bolts and the "pin bushings"? to have a forty year service life, just sayin.
:waytogo:
Six surfaces per caliper, if applicable.
 

R8rPhan

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Lots of people read this board dude, all different kinds of folks from all across the globe..

Since you are still pulling , it's probably a good idea to remove that caliper and sand the mating surfaces of the caliper bracket with emery cloth or similar.
Those flat surfaces should be lightly greased in addition to the caliper bolts. Examine them closely to ensure one hasn't developed a "rut" = from lack of grease that CAN cause a sticking caliper, resulting in a pull because the caliper is meant to "slide" aceoss all of those surfaces... At least four per side. That action must remain fluid or it'll hang up and pull.
Doubtful the General intended caliper bolts and the "pin bushings"? to have a forty year service life, just sayin.
:waytogo:
Six surfaces per caliper, if applicable.

@ $20 each, I'll just replace them.. Thinking about replacing the prop valve and all four flex lines too... Already budgeting for at least the calipers next month.. Will replace the pads too... and yeah, good point about the bolts and pins.. I'll replace those too..
 
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R8rPhan

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So, since I last posted here, had more brake problems..

After replacing the wheel cylinders and calipers, while on a trip down into the valley on a very hot day, I realized that my real brakes were not releasing after being depressed, and the truck was still pulling to the left when I hit the brakes... Had to drive 50 miles home with the rear brakes engaged... Needless to say, I used a lot of gas, wasted a lot of life on the shoes, and had no power coming up the hill..

Letting the truck sit overnight would release the rear brakes.. I surmised that the leaking wheel cylinder I had before masked this problem as it allowed pressure to be relived through the leak..

So I looked into possible causes for this and was convinced that the proportioning valve was the issue.. So I ordered one, and I decided to replace the leaking front crank seal at the same time...

So I replaced the proportioning valve and tried to bleed the brakes (using a bleed tool for the valve), but was still having a very hard time pushing fluid to the rear wheel cylinders, and bleeding the front right caliper was far easier that the left..

So the only thing left I hadn't replaced was the hard brake lines and the soft brake lines...

I disconnected the rear hose at the differential and pushed on the brakes.. almost nothing came out... Order all three soft hoses and replaced them (the fronts are kind of a bear to replace as getting to the nut that holds them where they pass through the frame is difficult)..

But that was the problem... Been a couple months since all that and they're still working great....

Brakes are freakin 'awesome' now.. Stops straight and smooth, easy to hold at a stop light, and there's still enough meat on the rear shoes that I don't have to deal with that for a while...

On to the next problem... Intermittent wipers..

..and the LEAKS!!!
 

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