I received and installed the Carter M6902 from Mancini last night. I noticed right off that the strength of the spring is much stronger than the spring on the Carter M6866 (one piece) unit that I pulled off.
The description of the M6902 pump shows 5.5-6.5psi but my mechanical gauge was showing 7psi plus/minus 1/2 or so. I was watching my float levels and they were right where I set them and my O2 gauges looked good, so the extra 1psi does not seem to bother my floats at idle.
I should be able to test drive it this weekend and hopefully this was the reason for my erratic lean conditions that developed out of no where.
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