[Guest]

I recently changed out my bars and had to change out the brakeline. When proceeding to fill the reservoir and bleed the brakes I get absolutely no fluid flowing from the reservoir to the bleed nipple (and no resistance of course). If I take the brakeline off all together I get no fluid dispelled from the master cylinder at all no matter how many times I pump the brakes. they worked fine 2 days ago. What’s going on?????? Thanks for any help.

 

[GrandPaulZ]

A little plug of solidified debris goop, most likely. Remove the parts, empty everything out, spray / flush with a spray can of brake parts cleaner, allow to dry, re-assemble.

 

[TRI-AL]

I've had the same sort of troubles. Sometimes, if things are working at all, it's better to leave well enough alone, but I don't and therefore seem to have more than my share of problems ...except with these old British relics, then it seems they CAN'T be avoided! Anyway, they seem to be pretty "touchy". Before you get too deep into things, I'd use a syringe or such to create a "vacuum" to try to suck the fluid from the reservoir through the caliper. If things seem "open", you may have to re-build the master cylinder. Seems that some of the cheap aftermarket re-build kits don't last as long as others. I used an original Lockheed brand last time & it's still working! I also changed to the more expensive "synthetic" brake fluid while I was in there. Good Luck & have fun! :hammer:

 

[GrandPaulZ]

You can also get an inexpensive brake vacuum pump at O'Reilleys or NAPA and it might be able to suck that stoppage past it's current point. I have used my little pump a dozen times at least, since I bough it.

 

[Guest]

Thanks guys. Yeah I guess it's plugged up. I'll try to dislodge it and if I can't get it I'll take it apart. If I still can't get it I'll throw it in the trash and throw a temper tantrum. Then calm down and just buy a new one.

You got a nice little collection going there GrandPaulZ.

Thanks again,
Type75

 

[KADUTZ]

Have you priced a new master lately?

 

[Mecchanica]

You have to "benchbleed" or prime the master. With the master angled up ( the lever down), put your thumb over the banjo bolt hole and pump. Allow the air bubbles out and then allow your thumb to seal it back up. A oneway valve. When you get pressure and a little squirt of fluid, then reinstall the hose with new washers. Use the banjo bolt as a bleeder nipple. Pump, break the bolt loose and allow the air out. Try to make the banjo bolt the high spot of the system so that all the air rises to that point. Finish with bleeding the caliper. Catch the fluid in a rag to keep it off of your paint. Keep some water handy to quickly dilute the glycol fluid, unless you have converted to DOT 5.

 

[Guest]

Thanks guys……I got it going. I took it apart and cleaned it out. Didn’t see anything wrong when it was apart but when I put it back together I had to get it primed by siphoning through the bleed hole. Then it started flowing. Right or wrong it worked. Regarding pricing a new one: I saw Nissin master cylinders with the lever similar to mine for around $80. But I saw other’s with the circular reservoir for $250 or so. Thanks again…

 

[okiecityflash]

You mention synthetic brake fluid, is that DOT 3? I haven't heard of that. DOT 2 will not be nice to the rubber internals. I wish dot 2 worked because it doesn't absorb water like Dot 3. I never changed brake fluid in my hogs and I learned an expensive lesson not changing my brake fluid at least once a year on the triumph. New master cylinder. I made a note of that NISSIN cylinder. Thanks and glad you got her going. Make sure the reservoir is mounted properly to the cylinder. It can only go on direction on my '79. Two different size holes on the bottom of the reservoir. :hammer:

[ This message was edited by: okiecityflash on 2006-12-26 00:03 ]

 

[KADUTZ]

Okie
I'm not familiar with DOT 2 fluid.
Synthetic fluid is DOT 5 there is an old service bulletin put out by Triumph of America stating not to use DOT 5 fluid.
(Also note DOT 5 is not the same as DOT 5.1 and the should not be mixed)
My preference is a DOT 3/4 brake fluid.

Also I don't understand the Nissan cylinder thing. but I doubt it is a bolt on

 

[Mecchanica]

DOT 5 works fine in Triumph and Norton systems. It isn't hygroscopic, like the glycol based DOT 3 and 4, so if you don't change your fluid yearly or if you live in a humid environment, you will have much better longevity with the DOT 5. If ya gots religion and change the fluid at least once a year, then the glycol stuff works fine.
DOT 5 is also more temperature resistant, but few of us will challenge the stock brakes on the street....and if you're racing, you probably don't have a stock Lockheed/Girling brake system in the first place.

 

[KADUTZ]

Biggie Fish

I know we have had this discussion before but:

Triumph of America Service Bulletin
Number 14-80
Subject D.O.T. 5 Silicone Brake Fluid
Models Al Disc Brake
Date May 1980

D.O.T 5 SILICONE BRAKE FLUID

Use of D.O.T. 5 silicone brake fluid is NOT RECOMMENDED in our Lockheed braking systems.
(note in the bulletin the words not recommended are underlined)

Note:Testing by Lockheed has shown that its use results in increased wear of metal components in hydraulic cylinders.

(end of bulletin)

now I ain't no genius but if the factory says don't use something I ain't gonna use it. if I were to own a vehicle that called for D.O.T.5 fluid then I would use it. if you want to use pineapple juice in your brakes thats your business.
also most guys on this forum have street bikes not race machines.
I think I know the difference between brake fluids but since you are the expert perhaps you could enlighten everyone here as to the difference between D.O.T. 5 & D.O.T. 5.1 fluid.
also what happens when you put straight D.O.T. 3 fluid into a D.O.T. 4 system.
I know you can type much faster than I can.

 

[okiecityflash]

SORRY folks, brain fart. Dot 5 is the number I was looking for. The later Hogs I've had ran it. As I recollect, being that Dot #5 does not absorb water, if you have air in your system it can produce rust. I don't know because I never changed the #5 in my bikes. Bad habit,as I never changed it in my Triumph either. That cost me big bucks.

 

[KADUTZ]

Okie
by the way AP Racing doesn't recommend using silicone brake fluid in their brakes. If you Google D.O.T. 5.1 BRAKE FLUID you can find their web site.