Rear axle exploded view

WOODPIE · 12:14 PM

Hello all!

On a recent trip, my '73 2.0l started making a tapping noise most noticable at cruising speed. I determined the frequency was that of the rotation of the wheels/tires. The tapping was loudest at a constant speed and throttle, but would almost disappear if I put the transmission in neutral and coasted.

The car is up on ramps now. I have detected some radial slop on the driver's side axle at the trailing arm end. I can bump it with the palm of my hand and moved it perhaps as much as 1mm, and the sound it produces is similar in tone to the tapping I heard on the trip.

I suspect either the rear wheel bearing or the CV joint, as both are of unknown age, but I would like more knowledge before I make up a parts list, pull out my credit card and click on the PP catalogue page. I don't want to buy new CV joints if I don't need to, and likewise anything else. I thought I had seen here a good exploded drawing of the rear axle and hub assembly, but I haven't found it with my searches. Thought if I could see a picture I could determine if the looseness in the axle is from the CV or bearing. DO any of you have a drawing they could post, or a link? If not, if any of you have gone through the rear-axle-bearing-change dance, could you chime in with an opinion of this looseness based on your own experience?

ONE OTHER THING. In accordance with the "while I'm in there" syndrome, I want to rebuild the stock rear brake calipers. My search on old posts in this area reveals that the Pelican Parts rebuild kits are (were) lacking some seals needed for the rear caliper rebuild if the caliper was going to be split, as I plan to do, and/or the seal(s) around the parking brake actuator. Has this been changed to be a more complete kit? Dave? Wayne?

I have done some work in this area of the car before, though not on this particular car, and it was many, many years ago. I don't remember how things fit together....too much (bong)water has passed under the bridge. I did fix that, though.

Thanks for reading and any help!

Ed

PS I have edited from 3mm to 1mm the amount of detected radial slop on the half axle, after having another look. Sorry for the exaggeration.

AaronM · 11-09-2002, 12:28 PM

Quote:

The tapping was loudest at a constant speed and throttle, but would almost disappear if I put the transmission in neutral and coasted.

Definitely sounds like a wheel bearing to me.

ZV

John2kx · John2kx's Garage

Ed,

I had a clicking noise that was only heard while putting a load on engine a few months back. This was with new CV's but "who knows how old" wheel bearings. What I found to be the cause was loose bolts securing CV axle on left outboard axle. With the car jacked up and in neutral, I could turn the rear tire and see the axle was not turning true. Put a wrench on the outboard bolts and found them really loose. Tightening solved my problem.

You could still have problems in either area you described (cv joints or wheel bearings). Before busting out that credit card, I'd do some disassembly and see what you've got. My failed cv's had obvious damage upon removal from car as bits of metal rained the shop floor when removed. Funny.......they made no weird noises prior to removal. I only pulled them to do a engine replacement.

Not sure if you can spin the rear hubs with bearings installed (cv alxes removed) and determine failure or not. I'm in the middle of upgrading to 5 lug conversion and have taken pics of just about every piece of project..........let me know if you want to see any particular part for clarity.

John

WOODPIE · 11-09-2002, 03:03 PM

John2kx, thanks for the reply and offer of pics. I agree, at this point, the thing to do is some disassembly and examination. New bearings aren't THAT expensive, and as I said, I don't really know their age. The records I have of parts and labor purchases from the two PO's show nothing in this area.

The CV could be bad as well, and it is the CV I suspect the most from my pushing and prodding this afternoon. The CV bolts are tight, at least on the inboard end. If the outer CV is assembled to the stub axle the way I think I understand it to be, it is there that I have the loose fit, play, slop whatever you want to call it. If you have a picture of that end of things, I'd really like to see it.

I am almost ready to pull the trigger on the parts purchase. The reasons are:

I don't want to tear things apart twice.

This car is currently my daily driver.

No garage to work in, and winter's coming.

My other car is (fortunately or un, depending on how you see things) a '75 914 with its own issues.

Really need to make holiday trip at end of this month to Pennslyvania.

So you see, I think I should get in, do the work, and get out as quick as I can.

Ed

gint · 11-09-2002, 05:08 PM

Are you sure that radial play isn't control arm bushings?

WOODPIE · 11-09-2002, 05:55 PM

ginter

The play, or looseness, I'm refering to is the steel axle itself. I can bump it with the heel of my hand and it makes a metal-to-metal "clink" noise. The trailing arm bushing is not new either, but I don't think that is the source of the tapping sound I heard at cruising speed. I'll check it out when I stick my head in there to do the work, though. Thanks

Ed

Zeke · 11-09-2002, 06:08 PM

Hmmm............a 914 witha 914 as a back up. Plans laid of mice and men often go.....well, you know the rest.

I think 2 things: Its the bolts like he said and that everyone that has a 914 should have a truck as their *other car.*

gint · 11-09-2002, 09:28 PM

I guess if I'd read your original post closer I could have "assumed" you had the wheel off and were checking at the stub axle itself. Whatever. You probably already know this too then. Make sure the outer cv bolts are tight. Easy enough to do. If you still have play, then your wheel bearing is shot.

John2kx · John2kx's Garage

Ed,

This is not a stock axle but the assembly and bolt locations are in the same place. You will able to inspect outboard bolts by peeping in hole of trailing arm.

The easiest way I know to pull the alxe:

1. Remove 30mm stub axle retaining nut.
2. Remove inboard alxe bolts that attach to trans. flange.
3. Disengage and lower inboard cv flange. (may have to removed
starter if your working drivers side)
4. Using 30 mm nut removed above, install backwards and tap
stub axle out of hub.

About a 30 minute job so far. I'd be armed with new cv's going into this. Pick up some new gaskets while your at it and only use the right tool to install/remove cv bolts. Pelican has all this stuff.

You should be able to spin hub(s) with axle removed and get a indication if your bearings are good or not. You'll be in for a weekend job if they have failed as well as many more issues with having the right tools for the job.

There is a good tech article on upgrading rear hubs to 5 lug on Pelican that will outline the whole job. I'm in the middle of upgrading my fronts and rears right now.....let me know if you need additional pics.

John

WOODPIE · 04:54 PM

John

Thank you for the pic. That is a beautiful axle and CV. I'd be tempted to wash and wax them every week if I put those on my car!

Some rain yesterday afternoon kept me from checking the outer bolts. From the symptoms, loose bolts could very well be the cause. I hope so.

Yes, I've read the tech article and also many posts that came up on searches that I ran. So I've sort of gear myself up mentally for the work if I need to do it.

Zeke

Plans? No plans here! How I arrived at this point with two 914s resulted from purely emotional, non-rational decisions. One of the arguments goes like this: All cars will eventually fail and cost you money. Drive a car you like so much, that when it happens, spending that money isn't regrettable.

Ed

11-10-02

Didn't want to bump this thread to the top. Outer CV bolts were tight. I guess that leaves me with an outer CV that is on its way out.