Failure modes for starters

[Jay Mackro <jmackro@domain.elided>]

Hey, I've got a question about the Bosch starters on 2L 115
Alfas.  My Duetto has a 2L engine (that's right, not the
original, yes, I know, it came from the factory with a 1600),
and it cranks really slowly.  My '76 spider, of course, also
has a 2L engine, and it cranks quite quickly.   

Engine condition is about the same - both have been rebuilt
within the last 25,000 mi or so, both have the high-compression
pistons that Shankle sells (~ 9:1, not 11:1 or anything), and 
both still have good compression.

A bad battery you suggest?  Nope - I tried pulling the battery
out of the spider, putting it into the Duetto, and still she
no crank so quick.  Bad ground / battery terminals?  No, the
Duetto is in really good shape there.  A bad starter ground?
Possible - guess I could attach a jumper cable between the
engine and the battery's "-" terminal.

Another possibility is simply that the engine in the Duetto 
is an from an earlier 2L, and as such, has the older starter
(1.1hp?), while the one in the spider is the type that has
the bracket at the front that attaches to the right motor 
mount (1.5hp?).  Does that make that much difference?  We're
talking the Duetto just barely turning, while the spider
just spins and starts.

OK, here's my bottom line question: is it possible for a 
starter or solenoid to degrade?  I know they can die outright, 
but can starters also wear in a way that diminishes their 
torque before they totally die?

Thanks

Jay Mackro

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