Purple Moo Cow Posted June 19, 2022 Report Posted June 19, 2022 It's been a while since I've gotten to post on here. Hope everyone's been having a good year. I PCS'd with my 48' down to Georgia and have recently gotten to start working on her again. I've managed to get her to run for a short period and figured I should move on to ensuring I have brakes in working order so I can hopefully finally drive her at least down my driveway safely. That being said... I pulled my master cylinder to rebuild. It was dried up with orange flakes and gunk. I cleaned it up as much as I could and put in new internals. I purchased DOT3 fluid to put in it but my problem now is I have no idea what fluid the previous owners have put in it. There was zero fluid to pull from anywhere but the lines that are in there were replaced within the last 10 years or so. So there's nothing to say that they're bad. Can I use DOT3 with the old lines? If there's synthetic fluid in the lines will I end up with no brakes? Or do I basically have to replace all the lines. If I do replace all lines, whats the recommended lines to use? N will I also have to replace the internals in each wheel for the breaks? I read in my manual that there are some hydrolic components to the brakes in the wheels? Is that right or am I just dumb. I haven't gotten that far yet either way. Appreciate the help either way! Quote
belvedere Posted June 19, 2022 Report Posted June 19, 2022 From the looks of that rust, yeah, you should rebuild everything. All brake fluid is synthetic, so no worries there. The DOT 3 you have is fine. Personally, I prefer DOT 5 since it doesn't absorb moisture, but everyone has their own preferences. Quote
Loren Posted June 19, 2022 Report Posted June 19, 2022 Brake fluid is hydroscopic, meaning it absorbs water. Water is not good for brake systems because of rust and the fact that it boils at too low a temp for brake systems. The brown crud you see is the result of water absorption. If you catch the water early, you can get rid of it by flushing the brakes with alcohol (it’s listed as fuel and can be purchased in the paint dept.) then use dry air to blow out the lines. If you have a vehicle which has sat for years with water contamination, you might find it a better bet to just replace everything, hard lines, flex lines, master & wheel cylinders. I had a lot of experience dealing with water contamination as a dealer mechanic. Early SAAB 900s had a vent on both sides of the hood. One side was over the HVAC inlet and the other was over the brake master cylinder. The factory installed a plate in the hood over the master cylinder which directed rain and carwash water away. The two largest export markets for SAAB were the US and the UK so making one hood and two different covers made sense. There was never a problem with the cars until a body shop had to replace the hood. If they put a used hood on, no problem. If they put a new hood on, they usually forgot to transfer the plate over the master cylinder. Water had a direct route right into the master cylinder and the hydroscopic nature of the brake fluid drew it in. The inside of the master cylinder would develop rust pits in the bore and became junk very quickly. The rest of the brake system fared better and on stick shift cars you had to use the alcohol treatment there too because they shared the fluid reservoir. The factory recalled the cars to install a plastic cover over the master cylinder in case the hood was ever replaced and deleted (read scrapped) every replacement hood with two vents in the spare parts inventory. All new cars and spare part hoods soon came with one vent over the HVAC. The factory reps toured all the dealer used car lots for some time to make sure any used car there had the plate and the recall plastic cover. Since it was not a defect in the design it was classified as a product improvement and so the government never got involved. Quote
Purple Moo Cow Posted June 20, 2022 Author Report Posted June 20, 2022 @Loren I appreciate the insight and background knowledge. I guess I'll be rebuilding or replacing everything then. @belvedere that's interesting, wonder why people would even bother using dot3 if dot5 is a better product. I didn't know any better Quote
Doug&Deb Posted June 20, 2022 Report Posted June 20, 2022 DOT 5 can make the brakes harder to bleed because of the master being lower than the wheel cylinders. It’s definitely better but be aware of that. DOT 3 is what would have been used when built. If you use it just flush the system every few years and replace the fluid and you’ll be fine. I agree with replacing all components. Use nickel copper line and don’t forget the rubber lines. 1 Quote
FarmerJon Posted June 20, 2022 Report Posted June 20, 2022 I don't like to use brake hoses if I don't know how old they are, or if more than 8-10 years old. They can collapse inside and cause major pita to diagnose. The reason major manufacturers don't use Dot 5 (silicone) is that it ISN'T better than Dot3/4/5.1. Yes it doesn't absorb water, so instead any water that gets in, sits in the low points of system, still causing rust. It doesn't perform as well, and gives a mushy pedal feel that many don't like. It also doesn't do a very good job lubricating seals. If your car only drives a few miles a year and is stored indoors, it may be a good choice but if you are going to drive it try a quality Dot 4 or 5.1 and just flush it out every other year. 1 Quote
moparfun Posted June 20, 2022 Report Posted June 20, 2022 I just did the complete brake system on the 54 Plaza wagon, I'm a low budget guy, the hard line kit from inline tube and it was less money than just buying the lines and bending them myself, the hardline kit fit perfect. The rest I able to get from Napa or Carquest at a better price than buying from the usual vendors. used DOT 3 for fluid. 1 Quote
Los_Control Posted June 20, 2022 Report Posted June 20, 2022 My thoughts ... Looking at the gunk in the master cylinder, I would be concerned about the bore on the cylinder. Clean it up & just pay special attention to the cylinder for rust & pitting, How far will you have to Hone it to make it work properly? Not trying to scare you, just maybe a 50/50 chance it is good or bad ... throw the dice and take a look. I put my master cylinder into a bucket of Berrymans carburetor cleaner & let it soak for a day or 2. Then gave it a light hone and new rubber parts. I think you could probably use some Brake cleaner spray to look at the bore before you spend much time on it. New master cylinders are available, there is also a possibility of having your old one bored & sleeved with a new stainless steel sleeve to repair it ... so do not throw it away. The brake lines, I would say if you can buy a kit of pre-formed lines and they actually fit ... go for it. For my truck I bought the rubber lines from Rockauto was common and cheap. I bought straight steel lines from local parts store, I used my old lines for patterns & bent the new lines to match, cut to length & re did the ends. My front brakes are completely new Hydraulically from wheel cylinders, rubber lines, hard lines all the way to my rebuilt master cylinder. Is a bit of a pita bending the steel lines .... But very doable if you have the old ones complete for patterns. Now I need to do the rear brake lines and I can not buy anymore steel lines in town I have to order so I ordered nickel/copper ... nicop. It is so much easier to work with, will or should last longer then steel. It comes in a roll. Here is a quick & simple trick to straighten it out. Drill a hole the same size of the line width wise through a 2x4 then pull the line through. You will end up with a really straight line, you need 3' pull out 3' & cut it. Then lay it next to your pattern line and bend it by hand to match. Will be really easy to bend up a professional looking line by hand in just a few minutes. Now take note in my photo what not to do. This is 5/16" line & I drilled a 1/2" hole just because that was what was handy. You can see it is not terrible but is not straight on the right side, The tighter the hole the straighter the line coming out the other side. Starting out with a line that looks like a snake kinda looks a bit amateurish. Starting with a straight line then gently adding the curves needed makes it look much better imho. Brake lines tucked into the frame under the car, looks may not matter to some ... some it would. Imagine creating fuel lines for a duel carb setup, Highly noticeable. Start out with a nice straight piece, then use pipe to bend the line around for shape & form .... you could come up with a masterpiece that looks like a professional built it. If you make a boo boo, you can always run the line back through the 2x4 to straighten it back out and start over. You can not do that with steel. I understand today we are just talking about getting working brakes. As you get further into the project, there are different sizes of lines. The brake & fuel lines are probably the same size 5/16" Except for the line going across the rear axle I'm guessing is 3/16"? Do you have electric or vacuum wipers? There is another line. There is the vacuum advance line from the Distributor to the carb. You have the oil filter lines & oil pressure gauge line .... I'm only trying to say, I started with steel lines from the beginning, now midstream I'm switching to nicop. If I had do overs I would have started with nicop in the first place. 2 Quote
sidevalvepete Posted June 20, 2022 Report Posted June 20, 2022 3 hours ago, Los_Control said: My thoughts ... Looking at the gunk in the master cylinder, I would be concerned about the bore on the cylinder. Clean it up & just pay special attention to the cylinder for rust & pitting, How far will you have to Hone it to make it work properly? Not trying to scare you, just maybe a 50/50 chance it is good or bad ... throw the dice and take a look. I put my master cylinder into a bucket of Berrymans carburetor cleaner & let it soak for a day or 2. Then gave it a light hone and new rubber parts. I think you could probably use some Brake cleaner spray to look at the bore before you spend much time on it. New master cylinders are available, there is also a possibility of having your old one bored & sleeved with a new stainless steel sleeve to repair it ... so do not throw it away. The brake lines, I would say if you can buy a kit of pre-formed lines and they actually fit ... go for it. For my truck I bought the rubber lines from Rockauto was common and cheap. I bought straight steel lines from local parts store, I used my old lines for patterns & bent the new lines to match, cut to length & re did the ends. My front brakes are completely new Hydraulically from wheel cylinders, rubber lines, hard lines all the way to my rebuilt master cylinder. Is a bit of a pita bending the steel lines .... But very doable if you have the old ones complete for patterns. Now I need to do the rear brake lines and I can not buy anymore steel lines in town I have to order so I ordered nickel/copper ... nicop. It is so much easier to work with, will or should last longer then steel. It comes in a roll. Here is a quick & simple trick to straighten it out. Drill a hole the same size of the line width wise through a 2x4 then pull the line through. You will end up with a really straight line, you need 3' pull out 3' & cut it. Then lay it next to your pattern line and bend it by hand to match. Will be really easy to bend up a professional looking line by hand in just a few minutes. Now take note in my photo what not to do. This is 5/16" line & I drilled a 1/2" hole just because that was what was handy. You can see it is not terrible but is not straight on the right side, The tighter the hole the straighter the line coming out the other side. Starting out with a line that looks like a snake kinda looks a bit amateurish. Starting with a straight line then gently adding the curves needed makes it look much better imho. Brake lines tucked into the frame under the car, looks may not matter to some ... some it would. Imagine creating fuel lines for a duel carb setup, Highly noticeable. Start out with a nice straight piece, then use pipe to bend the line around for shape & form .... you could come up with a masterpiece that looks like a professional built it. If you make a boo boo, you can always run the line back through the 2x4 to straighten it back out and start over. You can not do that with steel. I understand today we are just talking about getting working brakes. As you get further into the project, there are different sizes of lines. The brake & fuel lines are probably the same size 5/16" Except for the line going across the rear axle I'm guessing is 3/16"? Do you have electric or vacuum wipers? There is another line. There is the vacuum advance line from the Distributor to the carb. You have the oil filter lines & oil pressure gauge line .... I'm only trying to say, I started with steel lines from the beginning, now midstream I'm switching to nicop. If I had do overs I would have started with nicop in the first place. Good advice here. Thanks for posting. Helpful to anyone and encouraging for those dipping their toes into a job like this for the first time. ? Quote
plymjim Posted June 20, 2022 Report Posted June 20, 2022 Here's another option, White Post Restorations. They will sleeve your wheel or master cylinders then return them to you completely rebuilt. Not cheap by any means but I've never heard of their work being any- thing but first rate. Near you too. Near Front Royal, Va. They currently have my '38 Dodge master cylinder. I will tell you he's not a fan of dot5 brake fluid. Their phone # is 540 837 1140. They have a web site too. 3 Quote
belvedere Posted June 21, 2022 Report Posted June 21, 2022 On 6/20/2022 at 5:56 AM, FarmerJon said: The reason major manufacturers don't use Dot 5 (silicone) is that it ISN'T better than Dot3/4/5.1. Yes it doesn't absorb water, so instead any water that gets in, sits in the low points of system, still causing rust. It doesn't perform as well, and gives a mushy pedal feel that many don't like. It also doesn't do a very good job lubricating seals. We'll just have to disagree. I have converted multiple cars and bikes over the last 25 years, and none has had an issue from DOT 5 fluid. One of them is my Kawasaki ZRX1200, which I bought new in 2001 and converted probably a couple years later, and the same fluid is still in there. It will go faster in 2nd gear than our old Mopars will go period, so I'm sure not gonna mess around with brake issues on it. Works great - no mushy feel or other problems - as do my old Mopars with DOT 5. Mfrs don't use it because all cars now have ABS, and DOT 5 is slightly more viscous than glycol-based fluids. Besides , it is quite a bit more expensive, and that adds up over millions of new vehicles. I sure don't understand the "lubricating seals" comment. Most wheel cyl kits come with a little packet of...silicone grease. Apparently those seal mfrs think silicone does a pretty good job. Quote
Purple Moo Cow Posted June 21, 2022 Author Report Posted June 21, 2022 I appreciate all the responses and insight. I did look at the inside of the master cylinder, while there was some rust build up inside the reservoir the cylinder itself did not seem to have much pitting. I do intend to hone it, when I get one small enough to do so. The local parts store only had one appropriate for an engine. I guess I will have to order some larger brake lines as well, since I only purchased 3/16" so far. Part of me knew the right answer was to not be lazy and just rebuild or replace everything, my wallet just does not appreciate it. Still cheaper than paying someone else to do it though and quite a learning experience. Quote
desoto1939 Posted June 21, 2022 Report Posted June 21, 2022 When i was at spring carlise the White Post had a space and I was talking to their representative regarding the use of Dot 5 Silicone Brake fluid. He explained to me that his supplier of rubber parts does not guarantee the use of DOT 5 fluid in their reconditioned brake cylinder and mater cylinders. They are recommending Dot3/4. Long time ago WP did support silicone brake fluid, So their supplier of the internal rubber seals is the real issue not the leaving of the various components. Yes DOT 5 will gie you a softer pedal but at lest you know that the fluid willnot absorb water into the lines and since we donot drive these cars everyday that is why alot of owners switch to Dot 5. i hae had DOT 5 in my 39 Desoto for 30 Plus years. Rich Hartung Desoto1939@aol.com Quote
Los_Control Posted June 21, 2022 Report Posted June 21, 2022 While I have no experience with dot5 thought I would do a little reading on it out of curiosity. I do not think there is a right or wrong here. For @belvedereexample seems to work well for them. Also seems to be moisture condensation that causes a big issue. I think the climate you live in & how dry it is will play a big part .... such as a motorcycle. Sure we all have got caught in the rain from time to time .... typically a motorcycle is parked in a garage and driven on dry days .... Will probably never collect moisture. The big issue with seals is from properly flushing the system of dot 3/4 to switch to 5. Mixing the 2 the fluid will turn into a gel. Seems it is the seals & rubber pieces that are the most difficult to flush. The master cylinder & hard lines are quick & easy to flush. You need to keep flushing it to get all the droplets from the rubber pieces. Flushed properly it is not a problem for seals .... just seals make it harder to flush. Because dot5 does not absorb moisture, the water will collect in a lower portion of the system and will cause rust/corrosion in those spots. Because dot3/4 does absorb moisture .... the moisture mixed with fluid will not cause rust/corrosion. The soft pedal from dot 5 is from the brake fluid heating up after driving, getting everything up to operating temp the brake fluid gets hot. The pockets of water turn to steam causing the soft pedal. 8 minutes ago, desoto1939 said: Yes DOT 5 will gie you a softer pedal but at lest you know that the fluid willnot absorb water into the lines Brake fluid can not stop water from getting into the lines ... Dot5 simply will not mix with the water so your water puddles up on the low side. According to the author of this article on why they do not recommend dot5 with their brake systems. https://techtalk.mpbrakes.com/brake-fluid/can-i-use-dot-5 A good test of the writers theory. .... We need to flush our brake fluid every few years just as good maintenance. Check out your brakes pay close attention to the firmness of the pedal ... best if they are properly adjusted first but still, Drive it and heat them up and pay attention to the firmness of the pedal with the brakes good and warmed up. Now flush some fresh fluid through them and refill with dot5, take it out and warm them up and check out the firmness .... Is it the same? Is it more firm? According to the author the water turns to steam as the fluid heats up .... So you need to drive it and heat the brakes up, around the block will not work for a accurate test. I have no idea how your results would be. If the Author is correct, you just flushed your water out and now your brakes should be firmer, til more condensation collects. Or if the brakes do not change .... Maybe his story carries no water? ??? The only good point for dot5 out of the article was .... dot5 does not eat paint. So if you have a nice paint job, that alone could be the clincher to use dot5. Yeahhh ... that leaves me out. 1 Quote
Sniper Posted June 21, 2022 Report Posted June 21, 2022 I'll tell you what That power brake bleeder I got it the cat's meow. Makes it so easy to bleed brakes. Quote
FarmerJon Posted June 21, 2022 Report Posted June 21, 2022 7 hours ago, belvedere said: I sure don't understand the "lubricating seals" comment. Most wheel cyl kits come with a little packet of...silicone grease. Apparently those seal mfrs think silicone does a pretty good job. I am no professional wheel cylinder repair man, but with the few I have done in the past, the kits I currently have, and the various kits I opened when I worked at a parts counter years ago, I have never seen a packet of lube in a wheel or master cylinder rebuild kit. The hard rule I was taught about rebuilding wheel cylinders was to use brake fluid as your assembly lube. Absolutely every resource I have seen says DO NOT MIX silicone and glycol base fluids. Applying silicone assembly lube would totally fly in the face of what every manufacturer recommends. As an aside, just got a master back from White Post. Looks to be very clean work, I will deal with them again in the future. Quote
belvedere Posted June 22, 2022 Report Posted June 22, 2022 (edited) I can only speak from experience...I just suck most of the DOT 3 out of the MC, fill it with DOT 5, and bleed til there's purple at each wheel. Rick Ehrenberg, tech editor of Mopar Action, tells of similar experience. I guess each person should just do what they feel is best for their car.https://www.moparaction.com/2016/03/16/binder_juice/ Edited June 22, 2022 by belvedere Quote
Tired iron Posted June 24, 2022 Report Posted June 24, 2022 On 6/21/2022 at 10:28 AM, Purple Moo Cow said: I appreciate all the responses and insight. I did look at the inside of the master cylinder, while there was some rust build up inside the reservoir the cylinder itself did not seem to have much pitting. I do intend to hone it, when I get one small enough to do so. The local parts store only had one appropriate for an engine. I guess I will have to order some larger brake lines as well, since I only purchased 3/16" so far. Part of me knew the right answer was to not be lazy and just rebuild or replace everything, my wallet just does not appreciate it. Still cheaper than paying someone else to do it though and quite a learning experience. I purchased a nicop brakeline kit that came with all the fittings i needed for 20 bucks on ebay. There was enough tubing in the roll to do my whole car. Quote
Purple Moo Cow Posted June 24, 2022 Author Report Posted June 24, 2022 1 hour ago, Tired iron said: I purchased a nicop brakeline kit that came with all the fittings i needed for 20 bucks on ebay. There was enough tubing in the roll to do my whole car. That's good to know, I will check on there for a kit with the larger size line that I'll need. Appreciate it! Quote
kencombs Posted June 24, 2022 Report Posted June 24, 2022 (edited) 4 hours ago, Purple Moo Cow said: That's good to know, I will check on there for a kit with the larger size line that I'll need. Appreciate it! Careful with the eBay search for NiCop. There are a bunch of copper coated line sets there. Not NiCop, which is an allow of nickle, copper and iron, but a steel line made to look like it. I almost hit ' buy now 'before reading the fine print. I reported the false title and deceptive practice but it's till there! Lots of them. If it is significantly less than the going rate, read carefully. Look at the cut end above. taken from one of the suspect listings. Described as Edited June 24, 2022 by kencombs Quote
Tired iron Posted June 27, 2022 Report Posted June 27, 2022 Good catch Ken! It looks like the real nicop stuff is more like thirty, not twenty. Here's an example of the real deal https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.com%2Fulk%2Fitm%2F324350035230 Quote
Sniper Posted June 27, 2022 Report Posted June 27, 2022 You can get that same kit at RockAuto for less. Scroll down to the last two entries https://www.rockauto.com/en/tools/brake+&+wheel+hub,brake+line,brake+line,1820 1 Quote
keithb7 Posted June 27, 2022 Report Posted June 27, 2022 @Sniperwhat power brake bleeder? Do tell. Quote
Sniper Posted June 27, 2022 Report Posted June 27, 2022 5 minutes ago, keithb7 said: @Sniperwhat power brake bleeder? Do tell. Here's the thread Quote
Purple Moo Cow Posted July 23, 2022 Author Report Posted July 23, 2022 Ok people, my rear drivers side wheel cylinder was leaking. I pulled it, honed it, put it back together with the same rubber and no dice. So I ordered a kit from rock auto that claimed it would work on the rear. The rubber seal is not solid on the end, it has a hole in the middle...will this still work? My current seal is a solid rubber piece. Attached photo is the rebuild kit they sent. Quote
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