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Discussion Starter #1
Guys

I am trying to remove the complete prop from my 71 spider.. Ive undid the 4 bolts connecting to the diff and the shaft comes away easily.. (should oil come out)? Is it a case of undoing the 4 bolts on the front doughnut and then the whole unit comes away? (I've taken the centre bridge off)

Thanks
 

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You're half way there. Sounds like you only now need to undo the two nuts that hold the center support bearing and then the four bolts at the doughnut. If the doughnut is still "rubbery" it will help to clamp the OD to keep it from expanding when the flange is pulled away. A couple of long hose clamps connected together will work as a clamp (see pic). The the complete assembly can then be removed. No oil should come out due to the removal of the flange from the differential. The oil may have collected in the area due to a leaky shaft oil seal. Good luck.
 

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Discussion Starter #3
Thanks...

Is the oil seal easy to replace?

Do I clamp the doughnut?


You're half way there. Sounds like you only now need to undo the two nuts that hold the center support bearing and then the four bolts at the doughnut. If the doughnut is still "rubbery" it will help to clamp the OD to keep it from expanding when the flange is pulled away. A couple of long hose clamps connected together will work as a clamp (see pic). The the complete assembly can then be removed. No oil should come out due to the removal of the flange from the differential. The oil may have collected in the area due to a leaky shaft oil seal. Good luck.
 

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If the doughnut is in good condition then clamping will help with removal and re-installation. Do a good inspection of it to see if there any cracks and that the rubber is still good. Now is the time to replace it if it's old and tired. A new one will come with the clamp on it. As for the oil seal at the differential, it's not particularly hard to replace once you get the castellated nut off. This needs a special socket. Alfa suppliers have this tool available. If you do this you'll need to either carefully reinstall the nut to provide the same preload by marking the clocking prior to removal. Or torque to the required torque spec. I've not actually done this myself so maybe others have advice.
 

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No oil should come out due to the removal of the flange from the differential. The oil may have collected in the area due to a leaky shaft oil seal. Good luck.
This is not entirely correct. The inner collar of the differential flange goes past the seal, and oil may very well seep along the splined pinion shaft past the nut and collect inside the flange. A small amount of oil in the cavity between the propshaft and differential flanges is normal and nothing to worry about.
 

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Rooney - a couple of small things I learned when I pulled the driveshaft on my 71. Before you disassemble the two halves of the shaft from each other, be sure to mark them so you can reassemble them with the same relationship to each other. The shaft is balanced (obviously) and changing the alignment can upset the balance. I learned this from "The Driveshaft King" when I took the shaft to him to have the U-joints replaced. I had decided to have the driveshaft rebalanced anyhow since I had it out, but he asked if I had marked the pieces. Of course I hadn't. Anyhow, I had the U-joints replaced and the shaft balanced for about $120 total. (I bought my U-Joints from Centerline; the shop commented that they were good quality).

Next, take a picture of your 'olive' while the shaft is out and let the experts here opine on its condition.

Finally, be sure to Locktite the nuts where the driveshaft connects to the diff. On the 71, they are an odd size, (9 mm or something?) and different than most years making them hard to find if you were to lose one.

EDIT: "While you're in there" you may as well replace your doughnut unless yours is really new. My mechanic ,who is an Italian-car-only Alfa Specialist, hates the standard IAP /Centerline doughnut. He prefers the Spruell heavy-duty ones.
 

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Discussion Starter #7
Great advice... thanks..

My problem is that one of my UJ's needed replacing as I had bad vibration when pulling away from junctions etc. My mechanic replaced it for me (not alfa mechanic).

The car felt much better, however it now has a vibration when reaching 15-20mph which goes away once through the speed range, it returns when I slow down to the same speed?

I don't know if my mechanic marked the prop (thinking not)!

is it worth spinning and reattaching and see if it makes any difference?


Also, the 4 nuts at the doughnut end, are they a pain in the *** to loosen?



Rooney - a couple of small things I learned when I pulled the driveshaft on my 71. Before you disassemble the two halves of the shaft from each other, be sure to mark them so you can reassemble them with the same relationship to each other. The shaft is balanced (obviously) and changing the alignment can upset the balance. I learned this from "The Driveshaft King" when I took the shaft to him to have the U-joints replaced. I had decided to have the driveshaft rebalanced anyhow since I had it out, but he asked if I had marked the pieces. Of course I hadn't. Anyhow, I had the U-joints replaced and the shaft balanced for about $120 total. (I bought my U-Joints from Centerline; the shop commented that they were good quality).

Next, take a picture of your 'olive' while the shaft is out and let the experts here opine on its condition.

Finally, be sure to Locktite the nuts where the driveshaft connects to the diff. On the 71, they are an odd size, (9 mm or something?) and different than most years making them hard to find if you were to lose one.

EDIT: "While you're in there" you may as well replace your doughnut unless yours is really new. My mechanic ,who is an Italian-car-only Alfa Specialist, hates the standard IAP /Centerline doughnut. He prefers the Spruell heavy-duty ones.
 

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Any mechanic worth his salt would make sure the propshaft is assembled correctly and mark it accordingly. It may not be painted marks. Personally I use punched marks, as sometimes the parts are thoroughly cleaned and painted.

The new u-joint *may* be slightly off-center, and cause the vibrations you describe. However, it is just as likely that you should also change the second u-joint, the centre support or the flexible coupling ("guibo" or donut) to get completely rid of vibrations. If it was my car and the vibrations were noticeable I would renew everything while the prop shaft was out of the car and have it balanced. The very least would be to renew the second u-joint.

Edit:
Oh... And the three bolts at the coupling (donut) should be no harder to get at than those at the flange... Depending on how much of a gorilla the last person to do them was.
 

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Discussion Starter #9
yes I agree... the doughnut looks in good condition.. and the bolts are proving tough to loosen..:whistling: I may just remove the back end of the prop and check/replace the other UJ..




Any mechanic worth his salt would make sure the propshaft is assembled correctly and mark it accordingly. It may not be painted marks. Personally I use punched marks, as sometimes the parts are thoroughly cleaned and painted.

The new u-joint *may* be slightly off-center, and cause the vibrations you describe. However, it is just as likely that you should also change the second u-joint, the centre support or the flexible coupling ("guibo" or donut) to get completely rid of vibrations. If it was my car and the vibrations were noticeable I would renew everything while the prop shaft was out of the car and have it balanced. The very least would be to renew the second u-joint.
 

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Rooney, you mention four nuts at the doughnut end of the shaft, but I'm not clear on what you're referring to....the doughnut is held on with six nuts; three facing forward, and three facing back. if that's what you mean, they were well torqued but not impossibly so.
 

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Discussion Starter #11
Yes they are the ones that I am referring too... they are very tight! Do I need to undo all 6?

Rooney, you mention four nuts at the doughnut end of the shaft, but I'm not clear on what you're referring to....the doughnut is held on with six nuts; three facing forward, and three facing back. if that's what you mean, they were well torqued but not impossibly so.
 

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You'll only need to undo three bolts to free the propshaft. The usual tricks apply; soaking in penetrating oil overnight, breaker bar, impact wrench, "nut splitter", angle grinder etc. You might have some luck with heat, but you also may set fire to the donut.
 

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Discussion Starter #13
so far I've just removed the rear section... problem is that i don't think there is any noticeable play in either UJ's? any thing else to check on that part?


You'll only need to undo three bolts to free the propshaft. The usual tricks apply; soaking in penetrating oil overnight, breaker bar, impact wrench, "nut splitter", angle grinder etc. You might have some luck with heat, but you also may set fire to the donut.
 

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so far I've just removed the rear section... problem is that i don't think there is any noticeable play in either UJ's? any thing else to check on that part?
If you're sure about the joints, not so much to do - short of putting the shaft back in the car and rotating a quarter of a turn relative to the other half at a time with a test drive between each turn. Next stop inspecting center bearing and eventually balancing...
 
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