Jump to content


Photo

Brakes went out... repair or convert to disc?


  • Please log in to reply
25 replies to this topic

#1 AutoArt

AutoArt

    Newbie

  • Members
  • Pip
  • 46 posts
  • Location:Washington State
  • Cars:lotsa Zs

Posted 02 August 2013 - 09:11 AM

So I got a '72 521, and was really stoked about it for a quick second... I've been really busy the last month, so I didn't have a chance to drive her that much, but drove her 5 or 6 times in the last two weeks.  Everything seemed fine, outside of a quirk or two.  Specifically, the brakes stopped the truck when I pressed on the pedal.  Seemed a bit squishy, but I wrote that off as me not being used to drums.  Today, I noticed that one of the tires was a bit low, so I pulled her out of the driveway (to flat ground, the driveway has a bit of an incline to it) and got the tire pressure squared away.  Afterwards, I went to pull back into the driveway, and nothing happened when I stepped on the brake.  As I rolled into the garage, which I had thankfully left open, I pumped the brakes, (nothing), and finally threw her into gear and dropped the clutch.  Not in time, unfortunately, I left a nice scrape on the bumper of the car parked there.  I know nothing about brakes, and less than nothing about drum brakes.  If I pump the brakes a bunch, a little bit of pressure returns to the pedal, but not enough that I'd trust it to stop the truck.  It quickly loses what little resistance it gains anyway.  Took some pics--

 

KlcvczD.jpg

 

 

qMei2A6.jpg

 

 

uAU9pvK.jpg

 

 

The reservoir on the right has plenty of fluid, the reservoir on the left is really low.  The brakes worked fine last week, what could have happened in the last few days to change that so drastically? 

 

I have various extra brake parts, new shoes etc... is it worth it for me to get the brakes fixed, or should I convert to disc brakes?  Keep in mind that I don't have the skills to do the conversion/fix myself safely, so I'd either be paying a shop to do the work, or begging for a fellow ratsuner to help me out.  Another thread said it'd be about $400 for Beebani's conversion, but I'm assuming that's just parts.

 

Thoughts/advice/offers of help?

 

 

Thanks y'all!



#2 Eagle_Adam

Eagle_Adam

    Datsunahaulic

  • Banned
  • PipPipPipPipPipPipPipPipPipPip
  • 10,386 posts
  • Location:Beaverton, Or
  • Cars:1978 620 KC KA DD 76 610 coupe project Jessi's 77 710 wagon DD

Posted 02 August 2013 - 09:16 AM

drums are a PITA but they can be fixed, since you lost fluid in the reservoir there is a leak somewhere. Fill it back up and check each wheel cylinder for a leak. 


Chuck it in the Fuck it bucket, cus I'm done

#3 DanielC

DanielC

    Senior Member

  • Senior Member
  • PipPipPipPipPip
  • 4,647 posts
  • Location:West Linn,Or

Posted 02 August 2013 - 09:17 AM

In your picture, the right master cylinder, that has fluid is for the clutch.

 

The left master cylinder needs fluid.  That is for the brakes.  It need fluid, and then to be bled.

 

The brakes on a 521 are not self adjusting, like on a modern car.  You need to do that also.

 

I would suggest you take the time to learn how stuff works on your truck.  It is really self satisfying.  I would leave the stock system in place, until you understand it.

 

I doubt you could find a auto shop to do the disk brake modification for you for a reasonable price.  Not only is custom fabrication expensive, there would be insurance liabilities that a shop may not want to deal with.



#4 mrbigtanker

mrbigtanker

    Hall Monitor

  • Senior Member
  • PipPipPipPipPipPipPipPipPipPip
  • 11,875 posts
  • Location:Eastvale,Ca
  • Cars:Trailblazer ss/72 521/71 goon/454 SS/2016 canyon

Posted 02 August 2013 - 09:42 AM

very true ^^^^^^^^^^^^^^



#5 AutoArt

AutoArt

    Newbie

  • Members
  • Pip
  • 46 posts
  • Location:Washington State
  • Cars:lotsa Zs

Posted 02 August 2013 - 10:03 AM

Thanks for the replies, guys!

 

Eagle_Adam-- I got some brake fluid, I'm gonna fill & check like you suggested... stupid question #1, do I need to drive it first, pump the pedal, or just wait and check?

 

DanielC-- preaching to the choir, I'd love to learn how stuff works on my truck.  I know how satisfying it can be.  It's not a matter of taking the time... it's a matter of finding someone to teach me, or at least supervise me.  I have no problem diving in and, say, changing a starter or an alternator.  Or even brake pads on a disc brake system, I've done simple stuff like that before.  But I'd be worried from a safety standpoint about blundering around with the brake system.  Or other stuff that could cause catastrophic failure/damage if not done correctly.

 

I'd love to learn about everything about the 521, if I could find someone local to teach/supervise me, I'd even be willing to pay 'em.  I would be one happy camper.  I'd be even happier if they were willing to be paid in beer or artwork... :lol:



#6 Eagle_Adam

Eagle_Adam

    Datsunahaulic

  • Banned
  • PipPipPipPipPipPipPipPipPipPip
  • 10,386 posts
  • Location:Beaverton, Or
  • Cars:1978 620 KC KA DD 76 610 coupe project Jessi's 77 710 wagon DD

Posted 02 August 2013 - 10:08 AM

no need to drive it, nor would i till you bleed them.

 

fill it, have someone pump the brakes and check each wheel for leaks around the cylinder and hoses. If no leaks then bleed the system and go for a drive closed to home in-case you have to push it 


Chuck it in the Fuck it bucket, cus I'm done

#7 AutoArt

AutoArt

    Newbie

  • Members
  • Pip
  • 46 posts
  • Location:Washington State
  • Cars:lotsa Zs

Posted 02 August 2013 - 10:21 AM

Right on, thanks bro!  I'll be trying that, as soon as I can get someone over here to pump the brakes while I check, then bleed etc.  We'll see how it goes...



#8 Eagle_Adam

Eagle_Adam

    Datsunahaulic

  • Banned
  • PipPipPipPipPipPipPipPipPipPip
  • 10,386 posts
  • Location:Beaverton, Or
  • Cars:1978 620 KC KA DD 76 610 coupe project Jessi's 77 710 wagon DD

Posted 02 August 2013 - 10:24 AM

you can fill it and pump yourself then look if necessary 


Chuck it in the Fuck it bucket, cus I'm done

#9 Dawa

Dawa

    Senior Member

  • Senior Member
  • PipPipPipPip
  • 1,779 posts
  • Location:hawaii
  • Cars:73 620, 76 longbed, 96 240sx, 90 Z32 TT, 97 SC300

Posted 02 August 2013 - 10:25 AM

hey brother.

no one is born with a knowledge of brakes. we all gotta learn sometime. and it seems now is your time to learn.

 

im the same as you where id much rather have someone either show me how to do it or correct me if im wrong. i didnt

have that growing up. just about everything ive learned was on forums or the internet.

 

brakes are really simple. just from reading your explanation, i dont think you will have to replace much or anything.

theres definitely a leak. find the leak and fix the leak. if its just a flare nut that needs tightening, tighten it, using a

flare nut wrench. invest in a good flare nut wrench, the ones i had from HF stripped during my brake job. they dont

even require that much tightening torque, but its a bitch to LOOSEN them on our old trucks. my flare nuts stripped and

i had to replace them. luckily oreilly autoparts (and similar) stock lengths of inexpensive brake line that is already flared

and already has the correct flare nuts attached.

 

 

discs are better, and nice to look at. i love mine. i had planned to do a disc brake swap, and then i HAD to when one of the springs on my front drum brakes broke, perfect timing.


tumblr_nf8a5hLQY51qe7x6po1_500.jpg

lets all be nice to each other.

 

zilvia: dawagarage, 96 s14, 90 z32

clublexus: properd 97 sc300

 


#10 AutoArt

AutoArt

    Newbie

  • Members
  • Pip
  • 46 posts
  • Location:Washington State
  • Cars:lotsa Zs

Posted 02 August 2013 - 11:16 AM

Dawa-- thanks for the encouragement, brother! ...and thanks for the tip on the flare nut wrench, I'll probably be picking up a set so as not to strip out my brake system's nuts.

 

Yeah, I didn't have anyone teaching me car stuff growing up either.  What little I do know was mostly learned from the internet, and Chilton guides.  Trying to see details in those dang tiny black & white pictures in the Chilton guides, haha... I learn more all the time, though, and when I have kids I'll definitely be teaching them.  The ignorance stops here! Or at least gets reduced a little... :lol:

 

I definitely want to do the disc conversion eventually, but if I can fix the drums (and learn in the process), I'll do that first.  On a budget, etc.  Was just curious as to how expensive/complicated the conversion was.  If fixing the drums is as simple as finding a leak and tightening a nut or replacing a section of brake line, I'll definitely be doing that.

 

Thanks again, y'all!



#11 flatcat19

flatcat19

    Back in Black

  • Senior Member
  • PipPipPipPipPipPipPipPipPipPip
  • 20,098 posts
  • Location:Tri-Cities, WA/PDX
  • Cars:Smaller. Better. Slower. Lower.

Posted 02 August 2013 - 11:58 AM

Where in Washington are you?

Maybe a member can come help you out.

 

I'd say get brakes adjusted tight, top and bleed fluid, then see where you stand from there.

 

 

Brake shoes need to have as little play as possible.

Reason being is the fluid needs to push those against the drum.

Less play means less pedal stroke to actuate the shoes.


You can't hang if your nuts haven't dropped...it's physics


#12 datzenmike

datzenmike

    KING RAT

  • User Administrator
  • 70,894 posts
  • Location:Vancouver Island
  • Cars:'74 710 sedan, '76 710. prevoius... '78 620, '71 521, '68 510 new '76 B-210

Posted 02 August 2013 - 12:38 PM

What ever you do do NOT drive it until it is fixed.  The 521 has a single master cylinder for all the brakes, so a leak anywhere in the system causes a total failure of that system. Modern cars have dual masters which basically divides the brakes into two systems. If one fails the other will work to get you stopped, though at a reduced level.

 

As stated, fill the reservoir and pump the brakes. You may see or hear the fluid being pushed out of a broken line or dripping from a brake drum.

 

 

You could also remove all the wheels and drums and look for wetness.


Posted Image

#13 AutoArt

AutoArt

    Newbie

  • Members
  • Pip
  • 46 posts
  • Location:Washington State
  • Cars:lotsa Zs

Posted 02 August 2013 - 12:48 PM

Man, if a member felt like coming over and helping with this brake issue I'd be eternally grateful...

 

I stay around the Tacoma area, but the truck was (temporarily) parked just north of Seattle.  It's gonna stay there until I either fix the brakes or get her towed to a shop, though, not trying to drive with shady brakes obviously...

 

It's raining pretty hard here right now, but it's supposed to be dry from tomorrow on.  I got a bottle of brake fluid, and my bro's gonna let me borrow his floor jack, so I'll be doing the fill fluid- pump brakes- try to find and fix leak- bleed, tomorrow or the next day.  Got a Chilton guide and an internet connection... Gonna see if I can adjust 'em while I'm at it, thanks for the adjustment advice!



#14 datzenmike

datzenmike

    KING RAT

  • User Administrator
  • 70,894 posts
  • Location:Vancouver Island
  • Cars:'74 710 sedan, '76 710. prevoius... '78 620, '71 521, '68 510 new '76 B-210

Posted 02 August 2013 - 12:56 PM

The most likely leak is a wheel cylinder that converts hydraulic fluid motion into mechanical brake shoe motion. On an old 521 I would replace all four corners. This is not complicated but becomes expensive if paying a mechanic to do it.


Posted Image

#15 AutoArt

AutoArt

    Newbie

  • Members
  • Pip
  • 46 posts
  • Location:Washington State
  • Cars:lotsa Zs

Posted 02 August 2013 - 12:56 PM

Thanks Datzenmike, I definitely won't be driving her until I get this fixed! 

 

Yeah, I thought that both reservoirs in the pic were for the brakes, until DanielC clued me in. :confused:   That it's a single-cylinder system explains the total failure this morning!

 

I'm going to try to jack her up and look from underneath first, but if I can't find the leak that way (I'm thinking I will, but who knows) I'll try the removing the wheels thing.



#16 Eagle_Adam

Eagle_Adam

    Datsunahaulic

  • Banned
  • PipPipPipPipPipPipPipPipPipPip
  • 10,386 posts
  • Location:Beaverton, Or
  • Cars:1978 620 KC KA DD 76 610 coupe project Jessi's 77 710 wagon DD

Posted 02 August 2013 - 01:03 PM

with that much fluid missing you should be able to see the staining 


Chuck it in the Fuck it bucket, cus I'm done

#17 AutoArt

AutoArt

    Newbie

  • Members
  • Pip
  • 46 posts
  • Location:Washington State
  • Cars:lotsa Zs

Posted 02 August 2013 - 01:14 PM

Right on... I'm hoping I'll be able to find it & fix it.  Be nice if it was as simple as tightening a nut or replacing a hose!



#18 Eagle_Adam

Eagle_Adam

    Datsunahaulic

  • Banned
  • PipPipPipPipPipPipPipPipPipPip
  • 10,386 posts
  • Location:Beaverton, Or
  • Cars:1978 620 KC KA DD 76 610 coupe project Jessi's 77 710 wagon DD

Posted 02 August 2013 - 01:27 PM

its probably gunna be a wheel cylinder that went bad 


Chuck it in the Fuck it bucket, cus I'm done

#19 Juniper11

Juniper11

    Newbie

  • New Members
  • Pip
  • 11 posts
  • Location:Durango, CO
  • Cars:'71 Datsun 521, '01 Suzuki DRZ400, and a minivan

Posted 03 August 2013 - 07:35 AM

Repairing leaky drum brakes was the first thing I did when I got my 521. It was a great first experience of getting to know my car :)  My reasoning is if your going to keep the drums, make sure they are in tip top shape. I had two leaky wheel cylinders so I went ahead and replaced all 4. While it was apart I got the drums resurfaced, replaced all rubber brake hose, and new shoes too. This is also a great time to repack your front wheel bearings if your up for it. 

    The whole process took way longer than expected but I am so glad I did it myself. I never knew how much satisfaction stepping on brakes could bring!

IMG_1163_zps0bbe0484.jpg mmmm braakes

IMG_1167_zpsdb2958ef.jpg



#20 Dawa

Dawa

    Senior Member

  • Senior Member
  • PipPipPipPip
  • 1,779 posts
  • Location:hawaii
  • Cars:73 620, 76 longbed, 96 240sx, 90 Z32 TT, 97 SC300

Posted 03 August 2013 - 07:43 AM

that orange spring is the spring that broke on one of my front brakes making it mandatory 

for me to have to utilize my accumulated disc brake swap parts :)


tumblr_nf8a5hLQY51qe7x6po1_500.jpg

lets all be nice to each other.

 

zilvia: dawagarage, 96 s14, 90 z32

clublexus: properd 97 sc300