Why was the 8-cylinder MPI distributor cap changed?

[ksliger]

Just curious but does anyone know why Mercury changed the MPI distributor cap for 8-cylinder engines? The old cap/rotor kit is part number 898253T29 and includes a distributor cap and rotor buth with brass contacts. The new cap/rotor kit which supersedes it is 8M0060495 and includes a distributor cap with aluminum contacts and a rotor with a brass contact.

I have always heard that the cap with brass contacts is best for marine environments. If this is so, why would Mercury switch to one with aluminum contacts?

 

[Fun Times]

Because it appears they were having some runnability issues with the old cap's.

Because it appears they were having some runnability issues with the old cap's.

Service Bulletin
Bulletin No. 2011-06
2011-06 JULY 2011 ? 2011 Mercury Marine Page 1 / 2
Replacement Distributor Cap on MerCruiser MPI Engines With
HVS Ignition Systems
Scope
Worldwide
Models Affected
Models Covered Serial Numbers
All MerCruiser V8 engines with HVS ignition systems 0M300000 and above
NOTE: Only replacement distributor caps or distributor cap and rotor kits with box dates (as identified on the box) between January
1, 2011 and May 24, 2011 are affected by this bulletin.
48237
Situation
MerCruiser has received reports of a misfire condition occuring after recent installation of service replacement distributor caps.
The misfire typically begins to occur after 20 minutes of engine operation.
Correction
For parts already installed: Replace the part and file a warranty claim for parts and labor (see Warranty below).
For parts not installed but in dealer inventory: If the box date code is between January 1, 2011, and May 24, 2011, file a
warranty claim for parts only.
Replacement Parts
Original New Part Number
898253T22 Cap 884792
898253T29 Cap and Rotor Kit 8M0060495

 

[ksliger]

Re: Because it appears they were having some runnability issues with the old cap's.

Re: Because it appears they were having some runnability issues with the old cap's.

Thanks! That certainly makes sense! I had a brand new cap start misfiring after about 20 minutes. I looked at a lot of other things once it started misfiring since the cap was brand new. I finally figured out that the brand new cap had already gone bad somehow...