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Mc2100 Power Valve Gasket Leaks

Discussion in 'Builds and Fabricators Forum' started by Chilly, Nov 20, 2021.

  1. Chilly

    Chilly Active Member

    Guys,

    I think the MC2100 is near perfect carb for Jeeps with 258-304. One occasional error is to install the incorrect gasket for the power valve. There are one-stage valves (short) and two-stage valves (tall) and they need different gaskets. Photo below shows correct gasket for each type.

    Resized_20211120_180522.jpeg
     
    fhoehle and OzFin like this.
  2. Chilly

    Chilly Active Member

    My recollection is the two-stage valves cost a lot more and are an emissions thing to not lay in the fuel with reckless abandon. If you think old Jeeps are killing the world then those might be for you. I prefer the single stage valves.
     
  3. Chilly

    Chilly Active Member

    Using wrong gasket for your valve may result in leaks.
     
  4. OzFin

    OzFin Vintage Jeep Guy

    Good info (y)
    Thanks for posting it.
     
  5. Chilly

    Chilly Active Member

    The PV cover for single stage is a shallow cap like this. Two stage is has a deep circular area to accommodate the taller valve.
    Resized_20211120_182331.jpeg
     
  6. Chilly

    Chilly Active Member

    I have read the PV of a MC2100 is vulnerable to blowout from engine backfire. I've backfired mine for fun and didnt pop it. But I won't do it anymore.
     
  7. Chilly

    Chilly Active Member

    The MC2100 and intake manifold has some li'l bitty heat tubes for the choke. If you dispense with that stuff you'll have a vacuum leak. The carb has a passage to use vacuum to draw hot air through the choke. You want to block that port if dispensing with choke heater.

    The carb on my Jeep has a brass cap on the choke port where the tube used to draw. Then I tapped the little port under the carb and installed a set screw. Photo shows spare carb not capped or plugged.

    Resized_20211120_183110.jpeg
     
  8. melvinm

    melvinm Member

    Thanks for posting .