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Brake bleed niples

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jlaird

jlaird

Great Pumpkin
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Anyone have a source for the nipples that let you bleed your brakes by your self? Is actually a one way valve.

Don't get old, hard to get under cars and move around on the floor, need all the help I can get.
 
Outstanding, I bought the 4 brake set just now as I already have a clutch one installed.

Now for next question, is this the time to go to silicon brake fluid and if so how do I get the old stuff out. Just fill the reservoir with it and start pumping??
 
+1 on Rick's comments.
Wait on the DOT-5 conversion until you are ready to replace ALL the rubber in the braking system and when you do make the change, flush the metal lines very well to remove contaminants.
 
DOT 5 will not mix with water nor hurt your paint, It will not mix with Dot 3 or Dot 4 either. Dot 5/sicilone will float to the surface and leave a clean interface.
So, just add it to the MC and bleed, when the fluid comes out purple you know you have all the old stuff out. In fact if you flush the right rear, the longest line first, the rest becomes a non issue,


Dot 5 is also lighter so it stays on top and is bleed easily to get the old stuff out. It is not necessary to clean the cylinders and lines of the previous liquid used.

How cool is this, a bit more expensive but well worth it. A quart is plenty to do your hole system.
 
Jack, I've been an advocate of Dot 5 since using it in my MGB when it first came out in the 70's. However, since I've just finished rebuilding my BE master cylinder because the cup's had all swollen up and covered the bleed back holes I am now having second thought's. Either the Dot 5 has changed or the rubber in the master cylinders is different or, perhap's, some spurious fluid got added by mistake but the next rebuild I do will be back to Dot 4.

Kurt
 
I am going to take a shot at the silicone. Hope it works out, if not so be it.
 
jlaird said:
DOT 5 will not mix with water nor hurt your paint, It will not mix with Dot 3 or Dot 4 either. Dot 5/sicilone will float to the surface and leave a clean interface.
So, just add it to the MC and bleed, when the fluid comes out purple you know you have all the old stuff out. In fact if you flush the right rear, the longest line first, the rest becomes a non issue,


Dot 5 is also lighter so it stays on top and is bleed easily to get the old stuff out. It is not necessary to clean the cylinders and lines of the previous liquid used.

How cool is this, a bit more expensive but well worth it. A quart is plenty to do your hole system.
Click to expand...

I have NEVER heard this advice. If you want to change to silicone without changing all the rubbers in the system, the very least I have seen recommended is to flush the whole system with alcohol before introducing the DOT 5.
 
+1 again for Rick's comments.

Further to his comments, I have seen numerous (bad) accounts of people changing to DOT-5 without replacing seals that have been exposed to DOT-3 or DOT-4. The common complaint is that the rubber surfaces that have been exposed to DOT-3 or -4 sluff off and form a black gelatinous goo collecting in wheel cylinders and calipers. The goo isn't always the problem but its origins from old seals typically means the goo is discovered when people go looking for why their DOT-5 filled system has started to leak.
 
Jack
I STRONGLY suggest that you stick with DOT3 or 4 unless you do a complete changeout/purge.
DOT 5 is good but does have problems if you do it like you are planning!
BillM
 
nomad said:
Jack, I've been an advocate of Dot 5 since using it in my MGB when it first came out in the 70's. However, since I've just finished rebuilding my BE master cylinder because the cup's had all swollen up and covered the bleed back holes I am now having second thought's. Either the Dot 5 has changed or the rubber in the master cylinders is different or, perhap's, some spurious fluid got added by mistake but the next rebuild I do will be back to Dot 4.

Kurt
Click to expand...

My suppliers of brake and clutch bits for the Jag tell me, never, as in ever, use DOT5 in the system. The rubbers will NOT work with DOT5.
When a supplier is concerned enough to tell me that, I listen.
How much difference is there in basic LBC brake and clutch rubber bits?
Dave
 
Ok, you talked me out of the change. Back to the Dot 4 stuff. Should not be a big prob if I am real careful filling the MC reservoir. Only the two outlet lines were disconnected and so maybe a few inchs of fluid was lost at the most. Course I will pump until all the old stuff is out. Well let me change that, wife pumps while I am under the car. Gosh I hate it when that stuff leaks.
 
TOC said:
My suppliers of brake and clutch bits for the Jag tell me, never, as in ever, use DOT5 in the system. The rubbers will NOT work with DOT5.
When a supplier is concerned enough to tell me that, I listen.
How much difference is there in basic LBC brake and clutch rubber bits?
Dave
Click to expand...

The new TRW master cylinder for our Spitfire came with a warning not to use DOT-5 so I called the supplier to ask why. Their answer (which came from TRW) was not compatibility of DOT-5 and the rubber but that DOT-5 has reduced lubricity than DOT-3/4. In short, DOT-5 does not lubricate as well as DOT-3 or DOT-4 and could lead to premature seal wear. I have been told that White Post and other firms that rebuild hydraulics by sleeving discourage the use of DOT-5 for the same reason. Still other sources I have read said that DOT-5 is fine if the bores have a different surface finish than what is commonly used with DOT-3/4. Since the surface finish is controlled by the manufacturer... this doesn't matter much to us end users.

Having put my cards on the table, I will share that I have DOT-5 in all my British cars and none have had any seal related problems. I have used DOT-5 in our GT6 for 20 years now without any hint of leaks or seal failure. In each case the brake system had all new rubber installed and the metal lines were flushed. Using DOT-5 is a choice that you should make based on your expectations for the car and weighing all the information that is out there. Certainly one factor to weigh into this is the warranty on new components. Regardless, only implement DOT-5 when starting with clean, new components. You are inviting problems if you don't.
 
Will proceed with dot 4 when nipples get here so I can do it myself.
 
dklawson said:
The new TRW master cylinder for our Spitfire came with a warning not to use DOT-5 so I called the supplier to ask why. Their answer (which came from TRW) was not compatibility of DOT-5 and the rubber but that DOT-5 has reduced lubricity than DOT-3/4. In short, DOT-5 does not lubricate as well as DOT-3 or DOT-4 and could lead to premature seal wear. I have been told that White Post and other firms that rebuild hydraulics by sleeving discourage the use of DOT-5 for the same reason. Still other sources I have read said that DOT-5 is fine if the bores have a different surface finish than what is commonly used with DOT-3/4. Since the surface finish is controlled by the manufacturer... this doesn't matter much to us end users.

Having put my cards on the table, I will share that I have DOT-5 in all my British cars and none have had any seal related problems. I have used DOT-5 in our GT6 for 20 years now without any hint of leaks or seal failure. In each case the brake system had all new rubber installed and the metal lines were flushed. Using DOT-5 is a choice that you should make based on your expectations for the car and weighing all the information that is out there. Certainly one factor to weigh into this is the warranty on new components. Regardless, only implement DOT-5 when starting with clean, new components. You are inviting problems if you don't.
Click to expand...

My experience has been much the same, Doug. I have Dot 5 in two other cars at the moment and my MGB that I first put Dot 5 in in the 1970's is still around with excellent brakes that I don't believe have even been bled since I converted it. The problem with my Bug Eye has just got me spooked.

Kurt.
 
dklawson said:
Having put my cards on the table, I will share that I have DOT-5 in all my British cars and none have had any seal related problems. I have used DOT-5 in our GT6 for 20 years now without any hint of leaks or seal failure. In each case the brake system had all new rubber installed and the metal lines were flushed. Using DOT-5 is a choice that you should make based on your expectations for the car and weighing all the information that is out there. Certainly one factor to weigh into this is the warranty on new components. Regardless, only implement DOT-5 when starting with clean, new components. You are inviting problems if you don't.
Click to expand...

Some of you may know that I had a long association with Sierra Specialties (over 15 years). I found Joe to really know his stuff when it came to hydraulics and the quality of his work was considered to be the best. Certainly his customer service was unsurpassed. With regard to silicone, his advice against it was largely based on the lubrication issue, but there were others. When it comes to replacement/reproduction MC's many have warnings to not use silicone and will void their warranty if you do. In my personal experience, I have seen many mushy seals as a result of use with silicone, and I think that is mostly an issue with natural rubber products more than anything, but you should definitely replace rubber that has been used with glycol based hydraulic fluid. The system should be flushed with alcohol and lots of compressed air.

Other issues I've personally encountered is that because silicone is hydrophobic, any water that accumulates in the system will separate out and collect/ pool in the low spots of a cylinder or reservoir. As a result, corrosion can actually be worse with silicone unless you change it with regularity.

I've attached some pix of a Mini style master cylinder that rusted out, letting fluid escape the system. You can see where rust has enveloped from inside the reservoir, along the seam, which eventually rusted through to the outside. It was just a matter of time until this failure would grow more substantial. With a horizontal bore, this would develop along the floor of the bore. In this case, with the reservoir failing, the only way to correct it was to replace the master cylinder as well as the wheel cylinders.

IMGP0016sml.jpgIMGP0017sml.jpg
 
Nipples arrived today, front ones are in but of course no jacking required. Will do the rear tomorrow and the flushing of the lines and MC with all new dot 3 shortly there after.
 
All nipples in, car jacked in rear, now need to adjust mc rods then all fluid and bleed, soon as I find a partner in crime. All my local car buddies have died in the last couple of years, I'm almost afraid to make new friends.
 
Rear lines bleed now. Only front and clutch. Fronts easy of course. Those one way nipples really are the only way to go. Run the clear plastic line from the nipple up to a catch container where you can see the last foot or so of the line and pump a bit. When you get no more air all good, I hope.

Oh yea, no dirty brake fluid, all looks good, but I did run about a pint through the rear into the container.

It is so hot, sigh. Wish I could just stay inside.
 
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