Shaft Donuts

[RLeT]

Hi Everyone, I'm looking for some inspiration & expert help because I'm stuck.

I am replacing the shaft donuts in my 1977 (June) Alfetta 1.8L sedan.  The rear donut is a 18972 part number.  I purchased it from a quality supplier in Melbourne, who has only ever purchased these via part numbers and has never had a problem, and has had a number of transaxle Alfa Romeo cars.  The new & old units are slightly different.  The new donut has been supplied with an integral bush, as per the photo "New" (attached).  The old one had a separate bush, which is shown installed in the attached Photo "Old 1", and removed "Old 2".  The shaft has been repaired (see previous thread on a shaft crack at the coupling yolk) and once the donuts are installed, it will be balanced.  The trouble is they can't get the rear donut to fit.  It's a major machining shop in Perth, who have done a lot of driveshaft repair work in the past. 

They've contacted an Alfa specialist workshop in Perth (Ciliberti Motors) who couldn't help, and they reached out to some Eastern states contacts who couldn't help either. 

The integral bush won't come out.  The donut supplier is at a loss also, as he's only ever supplied the donuts via the part numbers and never had a fitment problem before.  The part numbers have been confirmed to both be 18972.  My supplier also asked if the new one may be for a shaft that has a centring ball pressed on, and swivelling outer collar that slips onto the donut.  The workshop would be able to make up a ball, but they suggested this wouldn't be an option (and I don't recall the reason why not at present).

I don't want to reuse the old donut, as it's got splits in it.  Does anyone have any suggestions? 

Thanks in advance.  Any suggestions will be enormously appreciated.

Richard.

[alfa duk]

This could explain

[Domenic]

they are 2 different couplings, they both run the same number and when ordering them, you need to physically take them off to work out which one you need.

the place you bought it off must be telling lies, as if they are an alfa specialist they will know that there are differences and would have seen it through out the years.

i'd send it back to source the correct one

[bonno]

Find attached link to rubber couplings that contains IPB for all Alfetta variants.


https://www.areseparts.se/en/ersatzteile/gt-v-6-116/antrieb/antriebswelle/antriebswelle-gt-v-4.html

[Beatle]

they are 2 different couplings, they both run the same number and when ordering them, you need to physically take them off to work out which one you need.

the place you bought it off must be telling lies, as if they are an alfa specialist they will know that there are differences and would have seen it through out the years.

i'd send it back to source the correct one

Why on earth do they have the part number when they are physically different?  There must be some suffix or something to differentiate, otherwise how would the aftermarket suppliers be able to order the two variants?

[Domenic]

The part # for the units are different, but on the casting on the rubber it has the same number that people tend to use when ordering them.

The only way to tell the difference is to remove the coupling from the tail shaft, as from the back they both look the same