Brakes leaking from bleed bolt

[damo03]

Hi All,

Bled the brakes at each 4 corners as I had the hose off at the rear diff, fitting new suspension. A week after bleeding the brakes I am getting fluid leaking between the threads on the bleed bolt and the caliper at all 4 corners. See attached photo. I wiped them dry a couple of days ago but they are all still leaking.

I haven't torqued them up to the 8nm the manual suggests, but it's pretty tight with a 8mm spanner and I've never had any problems before with other vehicles I've bled brakes on. Does anyone know what seals the bleed screw? Is there a o-ring in the caliper that might be perished or has anyone come across this before?

I'm guessing the threads on the bolts are a bit average or that there's a o-ring. Your help and experience is appreciated!

[tomwithannl]

The bleeder seals in the caliper with a taper. If it were leaking it would be coming through the bleeder hole not the thread. I would say it is just residue from bleeding. Keep wiping and I am sure it will dry up.

Tom

[erad]

The bleed screw seals with a tapered seat at the base. You may have a bit of crud under the seat. You will have to remove the bleed screw and clean it up and hope that there is no more crud under the seat.

[geopaj]

The bleed screw seals with a tapered seat at the base. You may have a bit of crud under the seat. You will have to remove the bleed screw and clean it up and hope that there is no more crud under the seat.

Agree. This is how I would approach fixing it

[damo03]

Cheers for the suggestions. I'll have to do the bleeding again.

Has this occurred to anyone else before?

[tomwithannl]

Sorry to disagree but if it were a bleeder not seating properly it would be leaking from the bleeder hole not the thread. It's the old point of least resistance, and you also wouldn't get it on all four. I still think it is just residue but then again it's just my opinion.

Tom

[erad]

tommwithannl: I tend to agree with your logic, but looking at the photo, the nipple part of the bleeder looks dry. The seepage seems to be coming from the thread area.

[Scooby]

Is it leaking out or just weeping?
Do all the nipples face up?
If they do when you bleed the brakes this fills the nipples with brake fluid and over time it seeps back out the threads.
Get some brake clean and spray into the nipples, use a tube off a wd40 can or use compressed air with care.
8nm isn’t very tight and easily achieved so would think you have them tight enough, and also think all 4 wouldn’t have crap under the seats at once unless you have a very dirt system.
Hope this helps.

[erad]

Damo03:
How did you bleed the brakes? I assume that you used a hose on the bleed nipple and had someone pump the pedal. The reason I ask is that I did this on a friend's Landbruiser 80 series and one of the nipples would not bleed at all. Eventually we removed it and still no fluid would come out. The hole in the caliper was choked up with crud. we cleaned out as much as we could, but he really should have totally striped the caliper and replaced the seals. He didn't and the beast is still running (and stopping) with no leaks. They are amazing vehicles.

[Fuzz260z]

I have this exact issue on my motorbike.
I have since removed the calliper and am yet to refurbish it. So I'm of no real assistance to you sorry, except to say your not alone. I hope refurbishing the calliper will remedy my problem.

[damo03]

Sorry to disagree but if it were a bleeder not seating properly it would be leaking from the bleeder hole not the thread. It's the old point of least resistance, and you also wouldn't get it on all four. I still think it is just residue but then again it's just my opinion.

Tom

I've had a look at these nipples at the wreckers and unless there is a lot of crud as suggested then I'm hoping it's just residue from bleeding out the nipples. As this could seep out the threads.

My gut also says that all 4 shouldn't leak and the system was nice and clean.


They're nice and tight >8nm torque too.

I'll give it another week.

Btw, a long range 145l tank at Jollys Ringwood, Melbourne for anyone interested. It's on a NL pajero escape.