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gritsop Green Cloverleaf

Joined: 23 Apr 2003 Posts: 766 Location: Ekali, Athens - Greece
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Posted: Fri Oct 03, 2008 3:52 pm Post subject: metal sounds from the differential |
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Hi all,
Just wanted your lights on the following.
Not a while ago I had the front wheel bearings and the outer CV joints replaced on the 33. I bought new SKF bearings (old ones were dry from grease) and CV joints made by an Italian brand Metelli.
The problem with the new CV joints was their perimeter is a little wider than the old ones and as a result the CV joint body was hitting against the hub.
This meant that the driveshaft would "lock" as the central nut was fully tightened. I solved this problem by getting a 3mm spacer to fit between the CV body and the wheel bearing as the photo indicates
Now that I have assembled everything, I notice that metal sounds coming from the differential only when doing a left side turn; doing a right side turn the sound does not appear.
I also noticed that the left driveshaft has a free play when i move it in and out (in a transverse manner) while the right driveshaft is solid with no free play. I have the feeling that the free play of the driveshaft is normal and the lack of it in the right driveshaft stresses the differential carrier bearings.
My question to the 33 gurus is whether free play on the driveshaft is normal and should be present on the transmission; in case you have any other suggestions I would be glad to hear.
Regards, _________________ Thanassis Gritsopoulos
1991 Alfa 33 1.4 IE
2001 Alfa 147 1.6 Distinctive
http://www.alfa-restoration.co.uk
Parts Shop: www.alfa-restoration.co.uk/shop |
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ZeNiTh-PbArM Alfa 33

Joined: 14 Mar 2003 Posts: 388 Location: Paris, France
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Posted: Fri Oct 03, 2008 7:43 pm Post subject: |
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Hi,
yes there must be free play in the shaft, what you have done is clearly wrong.
You should have turned them outer CV joints down to proper diameter instead of adding a washer.
The only workaround you have now is to raise your engine (there is lots of play at the upper mount) to expand the shaft a little. Tighten the bolt in the uppermost position and you'll see the rumble go away.
Note that driving with compressed shaft will ruin CV joints.
a while ago i repaired a car with bent chassis, the problem was exactly the opposite, shaft fully expanded because of distorted cross-member, i removed the circlips in the inner CV joint to allow for some play in the shaft. As far as i know the car still runs like that.
regards,
zp |
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gritsop Green Cloverleaf

Joined: 23 Apr 2003 Posts: 766 Location: Ekali, Athens - Greece
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Posted: Sat Oct 04, 2008 12:51 am Post subject: |
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Hi Zenith,
Thanks for the fast and accurate reply. In fact I am goin to look into that and try to slacken everything up.
One more question: While installing the new CV joints I ommitted one of the two washers as shown on the picture. If I installed those two all together, then the circlip on the CV joint would not lock up the driveshaft.
Is the presence of those two washers critical or do they just take up or fill in the slack ?
Regards, _________________ Thanassis Gritsopoulos
1991 Alfa 33 1.4 IE
2001 Alfa 147 1.6 Distinctive
http://www.alfa-restoration.co.uk
Parts Shop: www.alfa-restoration.co.uk/shop |
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ZeNiTh-PbArM Alfa 33

Joined: 14 Mar 2003 Posts: 388 Location: Paris, France
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Posted: Sat Oct 04, 2008 5:47 pm Post subject: |
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Hi,
i dont remember getting washers, there's a small spacer ring on oem shafts (spica) , and nothing on 16V (lobro). Did you compare respective thicknesses of your old CV rzeppa center with the new one? I suspect the new CV joint you have is badly out of spec, this happens very often with alternative suppliers (reminds me of a recent headache with aftermarket VW CV joints)
i wouldn't worry much about a little slack since the shaft is still held firmly at its other extremity.
by the way how did you remouve the outer CV joint? did you use ZP's magic tool?
regards,
zp
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gritsop Green Cloverleaf

Joined: 23 Apr 2003 Posts: 766 Location: Ekali, Athens - Greece
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Posted: Sun Oct 05, 2008 9:25 pm Post subject: |
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Hi Zenith,
Actually the CV joints look to be similar to the old ones but not the same Thats why I guess that the centre of the CV joint may be a little off.
The way I had the CV joint removed was simple ... I had four hands; Two hands holding the driveshaft and the other two trying to keep the locking circlip open and in the meantime punching the CV joint with the rubber mallet.
Yesterday I had removed the last remaining washer from the internals of the driveshaft/CV joints and the shaft can now easily move in and out with no more metal sounds and vibrations.
Thanks for the help ... really appreciate it. Now next repair is front suspension bushes. Boy this car really never ends...
Regards, _________________ Thanassis Gritsopoulos
1991 Alfa 33 1.4 IE
2001 Alfa 147 1.6 Distinctive
http://www.alfa-restoration.co.uk
Parts Shop: www.alfa-restoration.co.uk/shop |
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ZeNiTh-PbArM Alfa 33

Joined: 14 Mar 2003 Posts: 388 Location: Paris, France
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Posted: Mon Oct 06, 2008 12:12 am Post subject: |
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Hi,
from your description i understand that you had the shaft model with the circlips that you expand, located at the shaft side of the outer CV joint.
unfortunately most of the 33 shafts are fitted with a clips on the wheel side of the shaft, that needs to be compressed to remove the CV joint. When installing the CV joint everything's easy, but dismantling is a nightmare since you do not have access to the clips inside the CV joint, hence the use of a heavy puller.
Good luck with the bushes,
regatds,
zp |
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gritsop Green Cloverleaf

Joined: 23 Apr 2003 Posts: 766 Location: Ekali, Athens - Greece
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Posted: Mon Dec 01, 2008 8:04 pm Post subject: |
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Hi guys,
Although this thead is a little old and looked like all was solved, actually there was something going on.
There was free play on the shaft as I had mentioned earlier but upon left turns the knocking was still there whereas upon right turns all were ok.
So I start once again troubleshooting procedures to determine why the knocking sound appear only in left turns.
The troubleshooting was at last succesful... and its name is Upper engine mount.
As you can see on the photo the bush is off about 2 cm which concequently means the drivetrain is off by 2 cm towards the left side of the car. Thats why the knocking sounds appeared only in left turns as the drivetrain had already taken up the slack of the driveshaft and the differential carriers were further stressed beyond their design.
Once I had a new mount installed the knocking sounds dissappeared and the motor now rocks way much less than before. Its amazing how much hassle a little item can do!
Best regards, _________________ Thanassis Gritsopoulos
1991 Alfa 33 1.4 IE
2001 Alfa 147 1.6 Distinctive
http://www.alfa-restoration.co.uk
Parts Shop: www.alfa-restoration.co.uk/shop |
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ZeNiTh-PbArM Alfa 33

Joined: 14 Mar 2003 Posts: 388 Location: Paris, France
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Posted: Wed Dec 03, 2008 8:34 pm Post subject: |
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Hi,
there is a means of avoiding the problem by drilling a hole in the bushing housing then using a wood screw through the hole and into the rubber to prevent the bushing from drifting away.
Regards,
zp |
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BigAl P4

Joined: 06 May 2003 Posts: 2995 Location: U.K Surrey
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