Replacing a bleeder valve
 

Hello fellow Porschephiles,

I am about to replace my front wheel bearings in my 911 and will probably need to bleed the brake lines again since I am quite sure that "plugging the lines" after caliper removal will introdude some air into the system (what the hey do you plug 'em w/ anyways?). I know one of my bleeder valves is somewhat rounded off I figured I'd go ahead and replace this while I'm in there. So two questions:

1) I am assuming that turning the valve open to it's stop will then allow me to unscrew the rest of the valve from the caliper right? I sure don't want to snap this thing off in there and deal w/ a messy easy-out thread extraction and possible fragments of the threads in the system/caliper.

2) I use a Motive Power Bleeder (great tool BTW) to flush my hydraulic system but am wondering if I should not also go ahead and replace the front bleeder valves with speed bleeder valves for additional protection from introducing air into the system. I've heard mixed reviews on speed bleeder valves but the fronts seem to cost no more then the regular bleeder valves so I am considering this option. Any other pros or cons for using speed bleeder valves vs the regular valves? :roll:

On getting the bleeder screw loosened, I've found that a six-point socket is better than a wrench for breaking them loose initially. I'd be interested in hearing pros and cons of speed bleeders. I have a set for a non-P-car car but haven't installed them.

Brian, you can remove the caliper from the rotor and suspend it carefully without disconnecting the brake line. One possible method involves the liberal use of duct tape to secure the caliper to the strut. I'm sure there are other ways to do this, too. If you're going to remove the strut, then disregard my prior comments.

1) brake bleeder screws will unscrew completely out of the caliper body

2) I use speed bleeder valves and find them to be good for those times when you're working by yourself. I just ordered a set for the S calipers that will soon be installed on my 73E.

You can replace wheel bearings without removing the brake lines just suspend the caliper from the strut with a piece of “universal car repair tool (wire coat hanger)” while working on the hub. Unless you have something different the bleeders just unscrew as a unit. If you are going to use your Motive I don’t see why you would need the special bleeders.

:idea: I’ve found that if you do remove the brake line the bleeder caps (you do have bleeder cape, right?) make absolutely perfect “stops” for the hose. If you don’t have them the Porsche part for the turbo’s bleeders are less expensive than the aftermarket and have a nifty collar to keep the cap from “hiding” on you :!:

Sulli!

Hey man. Let me know if you need a hand, long time no see.

Excellent info - thank you all for the quick responses! I was hoping that I could simply hang the caliper out of the way to do this but was unsure. You gotta love these Bentley manuals - "To remove wheel hub, drop entire front end." :shock: The existing valves do have the caps on 'em so thanks for offering that solution as well. I plan on using the heat/freeze method for removing/installing the bearing races - just waiting for the wife to be out of the house before I pop the hubs in the oven. :wink:

Chris, or should I say, ahem, "Instructor Martin"! Hey man too long of a time! Wow, 2 Porsches now? U da man! Thank you for the kind offer! I remember when you did the front bearings on the SC. The procedure doesn't look too tuff so I think I should be ok (Doh! I think "Murphy" heard that) - seems that getting the races out/in is the big thing. If ya wanna come out to the house to visit/assist when I do this perhaps we could throw back some brews afterwards and catch up (or I could come to your house if ya don't mind putting up my Cab for a few hrs)! I am just waiting on my bearings to arrive at this point.

The races can be removed/installed without the heat/freeze drama. Just use a punch to knock them out, careful to not scar the hub. Carefully, tap around edge to get them started.
Use the old bearing to reseat the new race. Put race in hub, put old bearing in place, and tap around edge with hammer. Careful you don’t get them cockeyed You can also use the axel bolt to run the race in too, it’s just harder to make sure the race goes in straight.
Don’t use the new bearing; you can crack the “cage” installing the race
You might try a full service gas station that you frequent enough that they recognize you. They might be will to do the race removal/install for $20 if you bring in the hubs.

Seal/race installers are about $20 for kit containing several sizes or you can just barrow some.

Don’t forget to install the new inner grease seal

David,

Thank you for the info. However, after spending a few hours researching this I think I will still heat up the hubs before removing/installing the races and ever so gently drive the races straight in w/ a race installer after the aluminum has expanded a bit to make it easier. I come to this conclusion after reading a snippet of a Rennlist posting by Bruce A. Carr (works for eBearing) per ChrisBennet on PelicanParts (see http://forums.pelicanparts.com/showt...threadid=57441) which, IMHO, makes more sense to at least loosen up the hub's race seat via thermal expansion before removal/install to maintain the original tolerances of this finely machined German part (& why these parts are so expensive). Yes, I'm talking about 1000ths of an inch here but hey, I'd rather take the extra step to do it right. I can't imagine a gas station/hub press shop taking the time to heat the hubs up first (...them Porsh are just like my Chevy pick-em-up truck ain't they?) so I'll do it the right way myself. :D

Brian:

Dave is just trying to make things easier for you. His words of wisdom come from many years of maintaining his fleet of twenty-seven Porsches (or is it thirty-two now? I'm probably guessing low, as I have not been to his house for two days...), as well as helping out at least a couple of strays who wander into his garage every Saturday and Sunday.

What you are proposing is fine, he was just trying to let you know you don't need to go through that if you don't want to. Not everyone is comfortable playing with fire, or handling metal pieces that are a couple hundred degrees.