Front caliper drain plugs are leaking

I rebuilt my 84 VF1000F's front calipers. Now the one caliper's drain plug is leaking. I took it out when I cleaned the calipers, nd now it's leaking.

I dont see it on the Honda parts catalog, and I'm guessing since it's the original one, a replacement may seal up worse.

1) What kind of thread seal can i put on that will stand up to brake fluid?
2) What brake fluid should i put in, besides the recommended DOT4? The system will be flushed out anyway.

Thank you.

 

When I rebuilt my brakes, The bleed nipples had a good amount of corrosion. I took apart and blasted/cleaned the calipers and wire brushed the drain plugs. When I put it back together I used a little bit of teflon tape on the threads of the plug and bleed nipple and filled it up with the ATE dot4 Blue brake fluid. No problems in a couple hundred miles.

Are you referring to the allen key drain plugs or the bleed nipples?

If it's leaking through the tip of the bleed valve it could just be a problem of threads being stuck and it not being screwed all the way in?

 

Teflon tape like rpierce stated and clean the threads, the best fluid to use for these brake systems is DOT4.

 

Thanks...

I'm referring to the allen key drain plug at the bottom of the caliper.

Will teflon tape be eaten by the brake fluid? I was reading that some people recommend a thread sealer, like Permatex 59214 or 59235. Thoughts?

 

IMHO as long as you make sure the threads are nice and clean beforehand and no brake fluid is in them, with the plug tightened all the way the brake fluid really shouldn't make it to the threads.

I suppose you could use a thread sealant but those take time to cure and some might not like the brake fluid either.

 

Jeff:

Teflon tape will not be eaten by the brake fluid. It is incredibly chemically stable.

Teflon was the result at DuPont of a "failed" experiment that ended up with some goop in the bottom of the vessel. Thinking it was of no use, they tried to clean the container by burning the product out - no go; it wouldn't burn. Then they tried to disolve it with acid with the same results. As one of the original chemists later related, "That's when we began to get interested in it."

 

lol, good story. i read that there is dot4 resistant teflon tape.

i have tried tightening the bolt with about 25 ftlbs and it leaked, so that is my concern. i'll go the tape route and see what happens.

 

how about a photo ?? i'm not aware of ANY allen heads on the brake caliper except the pad pins.

 

they're on the bottom if you take the caliper off. So I cleaned up the allen bolt inside sealing cap with a dremel and put thread sealer on it. no leaks! i did the same dremel with the bleeder valves.

the pads on the right caliper had brake fluid on them. any chance of saving them with brake cleaner or should i spring for another pair of new pads?

 

Umm, I dont think the pads are good anymore now that they have become contaminated, spring for new pads I would think. Its unfortunate but I think necessary. I'm currently in the process of flushing my 5th gen brake fluid and it is taking FOREVER. I already went through 350 mls of new fluid and am having to repeatedly go back and forth between the front left and front right outers bleeding them with a mighty vac, as soon as I see no more bubbles I'll pump the mighty vac again and more dam bubbles. One time I let the resevoir get too low and I heard it hissing, I let more dam air in. So after like an hour I am going to bed and will try again tomorrow. Good luck with your new pads.

 

Image of allen bolt:

 

I won't comment on fluid on brake pads as I don't want anyone having a crash and saying that they didn't have enough brake.

CBR did you pressurize the system before you opened the valve to bleed them. Crack open the bleeder then close it before releasing the pressure on the master cylinder and repeating? Repeated air can mean two things. Either you are getting air back into the system because of technique or you have a leaking cylinder, banjo fitting or line.

Good luck guys.

 

Camo, thanks for asking, over the last 2 days I have been bleeding the brake system with pressurizing the pedal/lever and it is getting better, still air bubbles but not as much, but still not gone all the way, I would bleed for a little bit and get most air out to the point where the bubbles are few and tiny, and wait after an hour or so and repeat the process and see bigger, more air bubbles. So there may be a leak, but after doing this procedure to the clutch as well, I found out the same symptoms apply to the clutch line, where the bubbles get smaller and fewer, then wait an hour, redo the procedure and find more air, these lines dont look all that bad and if I had a leaking line or banjp fitting wouldnt the system show it as in wouldn't there be visual signs of hydraulic oil somewhere and lack of fluid in the resevoir? Which I have none of these signs, And both hydraulic symptoms worked fairly well last year. Just replacing the fluid for routine maint. I think there is just THAT much air in the system and it will take a while to bleed all out. On another note I am replacing the coolant and cant find the cylinder drain bolt, going to do a search right now. Tips advice?

 

It may be possible to get air in the line from the bleeder valve if you keep it open too long or unscrew too far. I put pressure on the MC and just open and close the valve in basically one motion. I recall having a problem like yours and had nothing wrong except my technique. When I put fresh solution in mine last month it went pretty fast.

The coolant drains pretty well if you remove the radiator hose at the water pump on the lower left side. If you want, open the radiator cap to let air in. There should be a port for air and fluid to bleed past the thermostat. Here you go bleeding again.

 

Camo, thanks for the advice, It's getting better and the pedal/lever feels good resistance, i'll likely be bleeding them a second time after a small ride to double check. Did I mention I'm doing the clutch too? And all in all so far I have gone through 3 bottles of 350 mL dot 4. So I dont think thats all that bad considering the long break lines. And I found the cylinder drain bolt for the coolant flush, it was where i thought it was, but found a pic on a tutorial on here to reassure. Thanks all.