Sunbeam Alpine: Differential Part One Issues and replacement

[Tim R]

We have just released Part One of a new two part video showing how the guys from Arrow 5 classic car workshop removed our defective differential and replaced it with a good second hand 3.7. If you are having differential problems this might be useful as it shows how to do the job in simple steps.

(Note: We paid full price to Arrow 5 for this work and received no other discount or incentive)

 

[jumpinjan]

That's a fine video..but what was the problem in the original 3.70 dif?
Jan

 

[Tim R]

Jan,
The original is sitting in my shed waiting to be stripped down and hopefully brought back to life again. Currently don't know what is wrong with it, it turns freely, then locks solid.
Tim R

 

[RootesRooter]

Did you check the tightness of the crown wheel bolts on both units?

 

[albeam]

Tim,

Good video, i wish my half shafts came out that easily. those guys made that differential replacement look easy. i guess they know their way around alpines.

Albeam

 

[Tim R]

Rootes Rooter, I was expecting to find loose crown wheel bolts on the defective Diff but they were tight, as were the bolts on the replacement.

Tim R

 

[bernd_st]

Tim, hope you secured the crown wheel bolts on the replacement Diff with Loctite. I'm really interested to see what caused your previous diff getting " stiff". Sounds like a pinion bearing gone. Should be easy to diagnose if if the diff itself is taken out from the housing. And yes, a thorough inspection of the crown wheel and pinion teeth is mandatory ;-)

 

[RootesRooter]

It's interesting that neither of the 3.7's had loose bolts. Loose/broken crown wheel bolts are a plague on Alpines, at least on later Series, but I've never noticed a mention of this happening on non-Alpine Audax cars or on the Arrow Range. I've run a couple of fastback Alpine diffs in my SV that were all tight. Are there any Brits out there who could enlighten us on their Arrow Range experiences?