Forum Discussion

xjruss's avatar
xjruss
Explorer
Oct 02, 2011

Onan 4000 carb pics

Hello,

I have an Onan Microquiet 4000, spec K, in my Toy Hauler. I'm working through the typical gummed up carb issue, but failed to make note of the orientation of the choke/throttle levers and linkage rods.

Would someone be so kind as to post a pic or two of their carb, so I can see how this thing should look when assembled correctly?

Thanks in advance.

Regards,
Russ
  • I dunked the carb in that carb cleaner can which is sold at auto parts stores.

    It was running fine last year. Now, it is dead.

    j-d wrote:
    How did you clean this carb?
    How's it running now?

    I got a tip on this site about getting the carb out from between the air filter housing and the manifold elbow:
    Stick a screwdriver into the filter element bracket and spring the plastic housing and foam gasket away from the carb.
    I backed out one of the screws that hold the housing in place and loosened another. Took a couple tries to get the screwdriver that pried best, but the carb came out and went back SO easily. Didn't take much, just enough to clear the choke plate. The way the carb's laid out, the choke and throttle won't both close. One sticks out making it hard to slip out and back in.
  • Hello everyone, it is that time again. Time the carb needs to be cleaned AGAIN!
    That sucks. I put Stabil in the gas, allowed the genny to run out of gas, it still wont start. AND...the starter motor's plastic gear/pinion is ripped AGAIN! I will start a thread about it.
  • j-d's avatar
    j-d
    Explorer II
    How did you clean this carb?
    How's it running now?

    I got a tip on this site about getting the carb out from between the air filter housing and the manifold elbow:
    Stick a screwdriver into the filter element bracket and spring the plastic housing and foam gasket away from the carb.
    I backed out one of the screws that hold the housing in place and loosened another. Took a couple tries to get the screwdriver that pried best, but the carb came out and went back SO easily. Didn't take much, just enough to clear the choke plate. The way the carb's laid out, the choke and throttle won't both close. One sticks out making it hard to slip out and back in.
  • Thanks to the pics in this thread and other stuff....today....I finally was able to get the genset started!

    The problem was that I did not put the carb together properly after cleaning it out. There is a flat metal washer which goes INSIDE the float bowl...between the solenoid and the float bowl....on the inside which I left out......it is not the copper washer which goes outside the bowl. Hence it was running way too rich...spewing white smoke.

    Moment I put the carb together properly....it started right up.

    Lesson learnt.......take pictures when disassembling complicated stuff like carbs.
  • try to buy a manuel.
    I replaced my carb with newone I bought,found out in the manuel
    that I had to adjust the Gov arm and spring etc.
    It had to be a certain way .
    Don. mine is Marquis gold 7000 onan
    Ps bought all these parts it wouldn't start, soon as got the parts delivered the darn thing started and ran and produced hydro, GO figure
  • try to buy a manuel.
    I replaced my card with newone I bought,found out in the manuel
    that I had to adjust the Gov arm and spring etc.
    It had to be a certain way .
    Don. mine is Marquis gold 7000 onan
    Ps bought all these parts it wouldn't start, soon as got the parts delivered the darn thing started and ran and produced hydro, GO figure
  • THANK YOU! THANK YOU!

    I did the same mistake as the OP... took out the carb for cleaning and did not note how the linkages are connected.

    Your pictures helps big time!

    Shows me that I must have connected the throttle lever backwards. Seems like it the linkage is supposed to be connected towards the outside of the genset. Mine is on the inside. Of course it won't start!
  • Thanks CloudDriver! Exactly what I needed. Good idea with the mirror too.
  • Here are pictures I took a couple of years ago. May or may not help.









    Mirror above carb shows top views of linkage connections


  • xjruss wrote:
    Hello,

    I have an Onan Microquiet 4000, spec K, in my Toy Hauler. I'm working through the typical gummed up carb issue, but failed to make note of the orientation of the choke/throttle levers and linkage rods.

    Would someone be so kind as to post a pic or two of their carb, so I can see how this thing should look when assembled correctly?

    Thanks in advance.

    Regards,
    Russ


    Don't have pictures, but this site SmokStak has Service manuals (for free) to download. Hope it helps