Brake Bleeder Thread Sealant?

[dsraven]

if it is leaking at the pipe thread area of the brass fitting, where there is a red sealant on the threads of the brass, then you may just take the fitting out, check the threads for damage, install some liquid thread sealer and re-install. if it is leaking at the brake line connection to that brass fitting, then first check the flare on the brake line for cracks or distortion, debris etc and also check the seat area in the brass fitting where the flared tube butts up and seals against the brass. you may have an issue there. look for cracks, a bump or line where there may have been a piece of debris on the seat when the line was tightened. this can distort the seat and you will not get a seal and will need a new fitting. also ensure you have the same angle on the two parts, the tube and the brass seat. the brass fitting wouldn't break the bank if you need to replace it, as well as the brake line.
try not to use the tape style pipe thread sealer because it can leave little pieces of the tape flapped out into the fitting and cause issues when it becomes free floating in the brake system. especially if you have to undo the line for some reason. a liquid style, like the red style used on the assembly now, is better. don't use anything on the threads of a flared fitting connection because they are not the sealing area of the fitting. that is done with the flare and seat. the threads simply tighten or loosen the connection. a drop of brake fluid or synthetic brake grease on the threads for lube if you feel you gotta use something, but use sparingly.

[dsraven]

are you sure the fitting in the res valve is a pipe thread, like the brass fitting, and not a flare fitting or some other thread? best to check the threads inside the res valve and also for damages to the actual res valve if it is an incompatible thread between the two parts.

[NeoJuice]

Thanks for the input dsraven.

Both residual valves are leaking at the pipe thread area of the brass fitting where the red sealant is on the threads in the picture. If I recall correctly my valve didn't have any sealant on it like in the picture. It was just brass on aluminum.

My flared 3/8-24 fitting that goes into the brass fitting is not leaking and my flare is good.

So I will pick up some thread sealant for the brass fitting. I will also remove and check for any damage.

The leak is right were the arrow is in the picture.

[dsraven]

maybe check the threads in the res valve for damage and also for the proper pitch to fit the brass fitting. if it is pipe thread then it will be a tapered thread and so it will continue to get tighter as you screw the fitting in until something either breaks, strips or the res valve cracks.
check a hydraulic shop for thread sealant or take the fittings with you and they may just dab some on there for you and tighten things down.
was the brass fitting part of the res valve when you bought it, like already screwed in and tight? maybe it was cross threaded a bit upon assembly. also check that the hole is drilled and threaded straight into the end of the res valve because if it is a bit crooked that may be the reason for the leak, somebody installed it straight when the hole is not straight, if you get my drift. you could always chase the threads on the end of the valve as long as you use some lube that will trap any filings on the tap and not let anything get into the res valve. maybe the hydraulic shop could help there and then use some synthetic brake grease on the tap-which you could supply.

[NeoJuice]

Yes the brass fitting was part of the res valve when I bought it. The picture I posted is the exact valves I got from kms tools. I flared my fitting on the one side and screwed in my 3/8-24 flared fitting into the brass fitting.

Since I was trying to fix the leaks I've tightened and probably over tightened the fitting on the brass end and maybe might have damaged the valve. I wasn't able to look at it tonight but hope to tomorrow.

[dwcsr]

I have to ask, If its leaking at no pressure or little foot pressure. Do you honestly think that a little red sealant is going to permanently stop 800 psi or 1200 if it has a booster when you use them at highway speed???? No answer needed.

[dsraven]

nope, don't think so.
the point was take it apart and see what you have for thread integrity and possibly install a NEW fitting with NEW sealant. as neojuice has said, he tightened the fitting as tight as he could get it. that may mean the brass fitting has stretched threads and may never seal properly again. he should take it apart, check the flare seat and threads in that section, check the threads on the pipe threaded side of the brass fitting as well as the res valve side, check the res housing for distortion, cracks, poor threads, etc. maybe chase the threads in the res valave before installing a new brass fitting. then install the new fitting with the appropriate thread sealant for the product inside the pipe and the type of thread being used. this would be the recommended repair at any shop, I assume, and is what I am sure any of us would do if we had to fix it. thread sealant isn't gonna stop this leak but they also don't put thread sealant on just to look good either. it acts as a thread lubricant as well as a thread sealer for the little discrepancies in the threads, voids if you will. there are several different types as well

quote from google "plant engineering"
"As the name suggest, pipe sealants, also known as pipe joint compounds, seal threaded pipe fittings and block the leak path along the threads."

so, not just me giving advice randomly. I would like to see neo get it right with NO leaks and have a safe brake system.

if you wanna read the whole thing about different types of thread sealants see the link.

http://www.plantengineering.com/sing...46dd34156.html


here is the link for loctite's hydraulic thread sealants along with a chart for their intended uses

http://na.henkel-adhesives.com/us/co...2SSF448695.pdf


and here is loctite's write up on the anaerobic thread sealer.

http://www.loctite-success.com.au/co...0compounds.pdf


hope this helps neo and anyone else with these issues. not trying to step on anybodies feelings here either, so please don't take it the wrong way.

[dwcsr]

Point me to where it says "DOT compliant" or 'For use in Automotive Brake systems" or "Glycol resistant' or anything other than brake fluid resistant, which is vague and can be anything including silicone. There should also not be any brass pipe threads on a brake system.

[NeoJuice]

I had a little time last night to pull the residual valves out of the truck.

I checked the threads in the valves and they look good and no damage, I also noticed that it's a tapered thread going into the valve so it will get tighter and tighter the more you put screw it in.

The brass fitting that goes into it possibly not so much and maybe looks like it has some possible thread damage and the brake line seat on the other side looked a little damaged.

So I went to Greg's distributors at lunch today and picked up four new fittings. I will try first without the Permatex thread sealant #59214 on two and see if I get any leaks and I will prep the other two with sealant and test.

I hope the wife will let me get some truck time tonight LOL. I will keep this thread updated.

[NeoJuice]

Update,

Got the new fittings into the residual valves and got them re-installed, I did use a little thread sealant on the new fittings just in case and let them dry.

Topped up my fluid and pumped the brakes like 20 times. Got under the truck and checked every line and fittings and no leaks!!!!.

Got back in the truck and pumped it like another 20 times. Got back under the truck and re-checked every line and fittings again and nothing is leaking! Finally!!!!! so now I'm finally ready to bleed my brakes.

But here is another question.

When I was pumping the brakes all those times I was watching the fluid level in the master cylinder. The pot that is located next to the brake booster (rear brakes) the fluid level dropped significantly low.

Then eventually the fluid pot filled back up so I know I must have a lot of air in my rear lines because it compressed the air in the rear lines then when I let off the pedal it forced it all back into the MC slowly.

Once I bleed the brakes this weekend hopefully I don't experience this issue again. Or...... the other problem might be is a placed my rear residual valve to far back (near rear drivers side tire instead of near the MC) so I would appreciate any thoughts on this. The front residual valve is right next to the MC.

[dsraven]

if it were me I would place the res next to the master right away while you are working on things anyway. that is how you see them placed in the diagrams from the suppliers. must be a reason I guess. can you move it there and just slide the line back some without any problems or is the line already bent around stuff on the frame so moving it will become another project?. that way the residual pressure is right there and the master doesn't lose anything to build up pressure in the line up to the res valve. I know, just me nit picking.

I understand you are not done yet but when completed i would suggest to support the lines along the frame because they tend to vibrate with the truck and if not supported they can crack at the supported areas, like the T or the fitting that supports the steel line to rubber hose connection. you can use rubber coated clamps or scavenge some plastic snap in fittings from a wreck. either way you can also use the hole in the frame for a wire loom clamp location as well.

[NeoJuice]

Originally Posted by dsraven

if it were me I would place the res next to the master right away while you are working on things anyway. that is how you see them placed in the diagrams from the suppliers. must be a reason I guess. can you move it there and just slide the line back some without any problems or is the line already bent around stuff on the frame so moving it will become another project?. that way the residual pressure is right there and the master doesn't lose anything to build up pressure in the line up to the res valve. I know, just me nit picking.

I understand you are not done yet but when completed i would suggest to support the lines along the frame because they tend to vibrate with the truck and if not supported they can crack at the supported areas, like the T or the fitting that supports the steel line to rubber hose connection. you can use rubber coated clamps or scavenge some plastic snap in fittings from a wreck. either way you can also use the hole in the frame for a wire loom clamp location as well.

Thanks dsraven, I'll see how it goes when I bleed the brakes and what happens I suspect it to be just a big air lock. I should be able to move it closer to the MC if the problem persists and I'll keep you updated.

I still have to attach the lines to the frame with clips. I bought plenty of clips to do that. Just didn't want to permanently attach anything until I knew I was done for good.

[dsraven]

ya, gotcha. I would say if you have probs bleeding it is because the air doesn't want to go through the res valve. that would be a reason to place the res valve close to the master with a slight uphill back to the master so any air can naturally find it's own way to the reservoir and out of the system. if you don't wanna move the valve too badly then have a buddy step lightly on the pedal while you manually bleed the line at the inlet of the res valve, then the outlet of the res valve. wear safety glasses too, you never know where it will squirt out to. have a few rags and some brake cleaner handy to clean off any painted surfaces that get fluid on them, it is like paint remover.

[my56chevytruck]

well, you're moving forward apparently. Yes, move the residual valve up closer to your MC, and secondly, I've never had to mount the residual valve in any position but inline with the brake lines. Either use a vacuum setup to bleed the brakes alone, or have a friend come over and bleed them with you underneatch. Make sure you keep the MC full of fluid at all times. Once you snug down the bleeders, give them another small turn to stop any fluid coming out. You shouldn't have to tighten down to far. Best of luck.

[NeoJuice]

Update,

After continuously checking for leaks everything was holding up So far.

So last night I attempted the one man break bleed. Everything went smoothly and now I have a nice firm brake pedal. Again after each wheel was completed I went and checked every line and fitting. No leaks. So the issue I mentioned with the rear fluid emptying and refilling back up was just an air lock in the rear lines.

To be sure everything was going to be good I had my brother come over today and do another bleed. Cracked the bleeder as he pumped and nice clean bubble free fluid coming out each wheel. Nice firm pedal. Topped up the fluid and closed the master cylinder for a long time I'm hoping lol.

I never thought that brakes would have taken me weeks and weeks to complete. In the end, I ended up using a tiny bit of thread sealant on the residual valve brass fittings. Maybe they should have come with it from the manufacturer like in the picture? But I needed to add some.

[dsraven]

nice,done deal. whats next?