Prop shaft tolerances

Started by djm411, May 30, 2012, 06:37:59 PM

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djm411

Given the problems that can occur with the propshaft on the alfetta, has anyone actually read the factory manual to determine the specifications given by Alfa? Well here they are.

Maximum out of balance at 4500rpm- 1 gr.cm.
Maximum run out of shaft - 0.15mm
Maximum run out of front section of shaft as measured at the centering dowels - 0.06mm
Out of square between dowels and planes of yoke of flexible joint - 0.05mm

Thoughts on these?

GTVeloce

You forgot the easy one - 7mm clearance between the bodywork and the shaft. I can't remember exactly which part of the bodywork but it's in the manual somewhere!

I got this one wrong once and chewed through the front doughnut in quick time. Lost the spacers from the rear engine mount and just used some old nuts instead. Didn't have original spacers to measure and didn't know at that stage about the 7mm. Oops.

Cool Jesus

Although the progress on my rebuild is a little slow, I have been researching the hell out of shop manuals, how to's and TSBs. I reckon I'm close to being able to write a thesis on the Alfetta. The attached TSB may raise a few eyebrows, propshafts were indeed balanced 'on the vehicles' at the factory and confirms that each individual piece of hardware MUST go back to where it was to preserve balance. What I found interesting was that balance adjustments are carried out - not by welding weights on, however by the changing the size of the yoke nuts or doubling up on a nut to adjust balance.

Has anybody come across differing sized nuts on the prop shaft yokes?
Present:
* '76 Alfetta GTAm 2.0 (project)
* '03 147 2.0 TS
*'12 159 Ti 1750 TBi
===================
Past:
* '10 159 2.2 JTS
* '89 164 3.0
* '98 Spider 2.0 TS

Cool Jesus

Just noticed on the exploded view of the prop shaft parts diagram it has differing sized washers for the yoke bolt and nut set up. Differing part numbers aswell?
Present:
* '76 Alfetta GTAm 2.0 (project)
* '03 147 2.0 TS
*'12 159 Ti 1750 TBi
===================
Past:
* '10 159 2.2 JTS
* '89 164 3.0
* '98 Spider 2.0 TS