1988 911 Carrera Bearing Measurement

[cmvasquez]

Hey everyone,

My name is Christopher Vasquez and this is actually my first post here on Pelican. I am a proud owner of an 1988 911 Carrera Cabriolet and I have been browsing the site for years now while restoring my 911. Until now I have been just fine reading through the awesome answers you guys have provided but I am now confused on the exact process of correctly seating my front wheel bearings.

If this discussion has already been beat to death I apologize, I could not find exactly what I was confused on. In re-installing the front wheel bearing play I was told to get everything back together and check for play in the bearings by simply using a screw driver to pry the washer just slightly. If little movement of the washer was experienced then I was told the bearings were seated properly. Is this the best way or is there another more precise way of measuring the play in the bearings (Front). For example using gauges to determine the play? Also in applying the proper torque to the rear wheel nuts would it be recommended to purchase a 300+ ft/lb torque wrench or will it suffice in using a breaker bar to estimate? Thoughts?

Also in heating up the wheel hub I was thinking about boiling them in water. Is this okay or is it preferred to heat using an oven. I just painted the hubs and am not sure if boiling them would ruin the paint or the metal. Thanks guys for your time and thanks for helping thus far in my build. Could not have done it without this site!

Also I know its customary for new members to upload pics of their cars so I will of course be doing so shortly here.

Thanks for your responses. Greatly apprecited

[Deadeye]

The washer method is the prescribed procedure. Set them this way and drive it to seat the parts then recheck and adjust if needed. Dial gauge accuracy is not required here.

For the rear axle nut you can guestimate torque (3 foot bar, 100lbs) and drive it to a shop with the proper sized torque wrench.

[E Sully]

A lot of auto parts stores have programs that will loan you a tool, so I would recommend calling the local stores about the torque wrench and wheel bearing tool. I was able to borrow the wrench from a local garage, as well as a bearing removal and installation set. While pulling the rear bearing was a little tough and needed the bearing puller, I put the new bearing in the freezer overnight and it went in fairly smoothly after cleaning things up without heating the hub.
The washer method on the front is a good method. Over tightening the bearing will do a lot more damage than slightly loose, and a recheck after a short drive is a good idea.

[porschenut]

Originally Posted by cmvasquez

...by simply using a screw driver to pry the washer just slightly.

Just to make sure there's no confusion about this, you're not "prying" the washer up, but simply pushing it around sideways using the flat of the screwdriver. You should be able to just barely move the washer.

[m110]

For the front bearing I would recommend putting a channel lock on the nut and tightening it down pretty good until it almost binds and then letting off and spinning the wheel. Do this a few times to seat in the bearing well.

After everything is nicely seated, spin the wheel and then tighten the nut until you get a feel of the point where the friction goes up and the wheel slows. Do this a few times and note the angle of the channel lock to find the right spot. The correct tightness is just before it seems the bearing is too tight and impeding the rotation. Then check the washer for play with a screw driver; should be snug but move freely. The wheel should move freely with no play.

If it is a new bearing, drive a thousand mi and recheck.

For the rear: I use a 2 foot breaker bar and put it as tight as I can get it. I have a large torque wrench and am usually close to 340ftlbs (for your carrera). A lot of shops just run it on with a impact gun until it is "tight". Can't really overtighten it with hand tools. You can also tighten it and have a truck mechanic torque it for a few beers. You are just concerned with loosening after a million heat cycles.

read this:
Rear Wheel Bearing Removal

[cmvasquez]

Thanks guys, with regards to the front wheel hubs I stupidly used a punch to remove the first set of races and scared the inside of the hubs slightly. I used a file to file it down slightly and some 2500 grit sandpaper to smooth the inside of the hub but is the hub still good to use. I figured that as long as the bearing race has a smooth surface to be seated to it would be fine but as I am new to this I just wanted to make sure that under load and once used on the street if this would be okay?

Also in pressing in the rear bearings I was told to freeze the bearings before install. Though it makes sense expansion/contraction wise is this okay still with the pre-grease packed bearings (bought on pelican). I would think the condensation would maybe not be ideal on the bearing grease and even the bearings. Am I over thinking this? Thoughts?

For the rear trailing arm is this a part that can be pre heated to aide in bearing install or is this not preferred. Is it okay to slightly heat with a butane torch or maybe even a heat gun or is this not necessary?

As always thanks for your input.

Cheers Gentlemen,
CMV

[pete3799]

As long as the bearing race still fits tight in the hub your good. If you removed too much material in the hub (sanding/filing) there's a chance the race will spin in the hub....not good.
As long as you just removed the high spots caused by the punch marks you'll be fine.
Freezing the rear bearings and heating the trailing arm seems to be commonly done. Haven't done my rears yet so i'll leave that for someone else to comment on.