85euro928

I just replaced the metal sealing rings on the PS hose banjo bolt for the second time and they're still leaking. Torqued it to 30NM both times. Anyone have a fix for this or should I just bite the bullet and buy a new hose, banjo bolt and sealing washers? Would rather have a fix as I'm getting tired of the down time, and I really shouldn't drive it as the leak is heavy. BTW, it's the bolt at the rack on the hose that goes from the rack to the reservoir.

Bill Ball

Examine the sealing surfaces the rings are trying to seal against. That return line to the reservoir is not high pressure, so it should seal pretty easily. Surprised to read "heavy" leak there. I would look more closely to verify that it is not a drip from somwhere above this fitting. That is the correct torque.

Landseer

Its possible to dress the washers with 600 paper with a squirt of oil. i've done it with the paper face-up on a table saw deck.

With care and the right flat dowl or jig, its possible to dress the rack and both sides of the rectangular hose surfaces a bit too, by hand.

Fogey1

If the metal sealing rings are copper, they're easy to anneal with a propane torch. That will soften them again and should make them seal better.

+1, too, to dressing them on medium/fine sandpaper on a flat surface if necessary.

Will
83S

85euro928

I didn't look carefully at the sealing rings the first time I installed them but I did the second and they looked fine (using just my eye). The sealing rings were new both times so I didn't think dressing them was necessary. My plan tomorrow is to remove the hose, pick the two best washers - dress and anneal them, then dress the banjo fitting. I guess I should also look at the rack with a magnifying glass to make sure its not cracked at the fitting. Also, I looked above the leak and the ATF is definitely coming from the banjo fitting, which is good news. I typically use a piece of 3/4" thick tempered glass for hand-machining small items so I should be able to use this to get at least the sealings rings flat and maybe, hopefully, the banjo fitting. At this point I have nothing to lose except another quart of ATF. Thanks for the help.

Rob Edwards

I had a recurrent leaker on the GTS- changed the sealing rings twice to no avail. Asked Greg to look at it, they leaked right after he re-assembled it, still up on the lift. He installed a new banjo bolt, cured the leak. Never could find a bad sealing surface on the bolt, but that was the problem.

gbgastowers

How bout a thin coating of Indian head shellac? It works great to seal seeping cis fuel fittings.

dr bob

I'm developing a love for teflon thread sealing paste (hardware store in the plumbing section) for fittings like these. A bit on the threads eliminates galling and keeps leaks through the threads down. Not an issue with a banjo fitting though. On sealing washers like these, a film on both faces keeps the washer from galling on either face. So far so good for me. I do reduce the tightening torque some, but generally because parts don't need to be so tight to seal. These fittings and bolts are typically 'wetted' by ATF during assembly anyway, so no change in friction part of tightening torque. Block drains, oil sump drain, differential housing fill and drain plugs all get this stuff now.

Mrmerlin

its quite possible that the hose end of the connection has been deformed, from over tightening,
a similar thing can happen to the short metal line that connects the fuel pump to filter.
This can be verfied by examining the washers you remove if they have small lines in them then they are not fitting flush to the hose, thus a new hose end is needed.
That said get some loctite PTFE non setting pipe sealant and put a small bead around the head of the bolt then smear some onto the washer then smear some onto the washer thats fitted between the rack and hose and also a small amount on the bolt threads then fit the bajo to the rack, if it still leaks then a new banjo bolt should be tried and then if still no good then a new hose

85euro928

I pulled the hose assembly yesterday and inspecting closer noticed that the banjo had a ridge on one side where the original washer had sat for the last 27 years and on the other side there was a fairly sizable radial groove. So with nothing to lose I took a wide fine file and slowly smoothed the machined surface on both sides until the mating surfaces were flat. I then annealed the sealing washers, ran them on some 600 until they were shiney and smooth, and installed them using PTFE on all mating surfaces and the threads of the bolt. I'm very happy to say that I drove it to work today and no leaks so far
Thanks for the help guys.

TheFrunk

@Mrmerlin what loctite number would that PTFE seal be? I see a lot of different ones (some crazy expensive) and I am unsure what to get or even what I can get on this side of the pond. Perhaps some gasket seal would do the trick, or would that ruin getting it undone at some point? Or even something general like loctite 243 blue medium strength threadlocker?

Mrmerlin

LOCTITE® 567 - Henkel Adhesives


Note make sure you have removed the old sealing washers from the banjo bolts .
use a razor blade as the washer can look like it part of the head of the bolt.

use new sealing rings ,
take a stone and surface the pipe fittings to see how flat they are ,
its possible the pipe fitting could have been crushed out of plane.
If so then you may have to replace the pipe.
Use the sealant sparingly you dont want it to squeeze out into the fluid .

TheFrunk

Thank you, I'll try that or something similar. If I can get it loosened that is, so far I could not get it undone yet. Good suggestion of using a stone, I happen to have some new unused whetstones lying around, that seems like a plan.

Geo55

https://www.mscdirect.com/product/details/40987893