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Posted by: draganc Oct 15 2017, 04:32 PM

Hi guys,

I have completely rebuilt my brakes incl all hard and soft lines.

I had the car on jack stands (what else) for the past 6 months and activated the brakes including parking every 1-2 weeks with firm pressure feel and no leaks whatsoever.

Yesterday I took the car of the stands to turn it around and get it in position to install the engine again.

Everything worked out just fine until I saw this spot underneath the rear right wheel:





Further quick investigation revealed "wet" spots in both trailing arms:



Again, no leaks for the past 6 months until I put the car of the jack stands and pushed/rolled it around for 100ft.

I was pressed for time and only had enough time to take off the rear right wheel to quickly glance at the caliper, which was professionally rebuilt and was dry on the outside.

Posted by: draganc Oct 15 2017, 04:35 PM

Here the pic of the rear right caliper:



Everything looks dry to the touch!

Any ideas/suggestions before I take the rear end apart?

Thanks in advance!
d

Posted by: rjames Oct 16 2017, 01:30 AM

Who rebuilt the brakes?

Posted by: BillC Oct 16 2017, 06:48 AM

Are you sure that's brake fluid on the floor? There's no easy way for brake fluid to get inside the trailing arm like that, especially if the car has just been sitting.

What grease did you use on the CV joints? Did you remember to install the cardboard gaskets when you installed the axles? Maybe the clear fluid is oil separating from the grease and dripping out.

Posted by: draganc Oct 16 2017, 12:16 PM

Actually, that was my 2nd thought after my rant has saddled.

IIRC, I did use the gasket but I guess I'll have to verify now.

Posted by: draganc Oct 16 2017, 12:28 PM

Any way/method how to test for brake fluid? Which btw I find difficult to believe that both calipers and in particular my work :-) has failed at the same time.

Posted by: GregAmy Oct 16 2017, 12:48 PM

Be a real technician: smell and taste it. Brake fluid is very bittersweet to the tip of the tongue, CV grease smells a lot like molybdenum (somewhat like rotten eggs).

GA, who can blind-taste-test just about any automotive fluid/grease...and that education wasn't by choice...

Posted by: Mark Henry Oct 16 2017, 12:58 PM

Where did you get the brake lines? single or double flare? It has to be double flare.
I prefer not to taste test brake fluid...

Posted by: rjames Oct 16 2017, 01:21 PM

Yeah, don't taste the brake fluid. As stated previously, smell it. It smells much different from the CV grease.

Can't imagine your CV lube grease separated at all, let alone to the degree that you'd have liquid dripping on the floor, unless they were packed with the wrong stuff.

Check your brake lines and calipers thoroughly for the source of the leak before you go removing the CVs. If you do remove the CVs, you'll need to new schnorr washers when you reinstall them.

Posted by: draganc Oct 16 2017, 01:29 PM

good questions! lines are double flare and I think I will pass on the tasting experience. already having enough gray hair.

it's been a while since I installed the axle/CV joints: can I "drive" them out w/o damaging the wheel bearing, after I remove the castle nut?

next step is to remove the caliper, dust shield and brake disk for inspection.

ps: the top bleed screw is a quick bleed type.

Posted by: draganc Oct 16 2017, 03:09 PM

had a quick coffee wrenching break.

the calipers, pads and disk are bone DRY!



i went through my parts stach and found two tubes of bearing grease, and i'm 99% sure that i have used the literally "no name" grease for the CV joints that it came with.

squeezed out some samples, wait for it..............bang!



the no name brand came out in a very clear "oil" and grease fashion, whereas the name brand is just simple grease.

i guess that's the best proof that letting a old cars sit is not good.

next stop taking the axle and cv joint out/apart.

Posted by: rjames Oct 16 2017, 03:50 PM

Using no-name grease for this application isn't good either. Glad to see you're replacing it with the good stuff.

It's been a while since I've done this, but i think you can remove the whole axle without hurting the bearings. It is when you remove the hub that the bearings are damaged. Somebody please correct me if I'm wrong here.

Although, how old are the bearings? I mean, y'know, while you're in there...

Posted by: Cracker Oct 16 2017, 04:53 PM

Shock fluid

Tony

Posted by: draganc Oct 16 2017, 05:55 PM

Thanks, I also thought about it but they are new - just like bearings - and dry.

Posted by: 76-914 Oct 16 2017, 05:59 PM

To test put a drop on your paint. If it bubbles up it's brake fluid. When looking for a small leak use a single sheet of toilet paper. A pin head size drop of any fluid will make a nickel sized spot on the tissue.

Posted by: rgalla9146 Oct 17 2017, 03:13 PM

Maybe you lubricated the splines of the stub axle before installing ?
It's got to be the CV gasket, the wheel bearing (not likely) or the hub/stub splines.
It's no picnic to remove the outside CV or the stub axle.
You've got little choice.

Posted by: porschetub Oct 17 2017, 08:18 PM

This one had me thinking how brake fluid could even come out of the inside of the trailing arm ,I would try rotating the the axles to mix up the grease a bit,I'am running quality cv grease and no seals between axles and flanges "0" grease getting out.
Good luck.