Evaluating the alternator mounting bracket upgrade

A potentially huge project versus failure at some future time

December 4, 2012

Universal M25 Service Bulletin #193 - DC Alternator Mounting

Critical upgrade - You bet I take that seriously. Service bulletin #193 says the early Universal M25 alternator bracket should be replaced and there is a conversion kit for this. The bracket prone to failure is the kind with the adjusting arm that goes over the top of the alternator. The kind that's on Reality Check. There's some horror stories on forums about the bracket failure. So what's the problem? For me, it's the studs on the exhaust manifold that the bracket is to be attached to. They're too short, this means I have to take the manifold off and replace the studs with longer ones.

Studs on exhaust manifold
4 studs on exhaust manifold have to be replaced with longer ones

What's removing the exhaust manifold entail? This thread "Retro Alternator Bracket" on the Catalina 36 forum describes the issues with this project pretty well.

Fun project? Hmmm...

exhaust manifold
Exhaust manifold

Alternator Bracket mounted directly to gear case cover, adjusting arm over the top of the alternator
Alternator bracket mounted directly to front gear case cover, adjusting arm over the top of the alternator
Alternator mount conversion kit parts
Alternator mount conversion kit parts, page 46 in the Parts Manual

Parts & Supplies

NOT a definitive list, this project is still on my To-Do list

  • Conversion kit PN# 256891, Catalina Direct PN Z2738
  • 50/50 Antifreeze/water mix to refill coolant system (Prestone).
  • Exhaust flange gasket.
  • A trusted mechanic! Those manifold studs may be a problem.

Service Bulletin #193

Universal M25, M25XP Parts Manual, (Publication #200142)


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