Volvo RWD 120-130 Forum

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Mikuni drivers. 120-130

The mikunis on my '69 rebuilt B20 seem very difficult to tune (no more fuel please).
I put a Holly in line FPR and set it a 2psi and it still gets too much fuel...I set up a sort of a over flow "tank" for the bowls and I'm constantly having to empty that.
Symptoms?
-I have to really let it warm up before I drive it or it just sputters, pops and stalls. So I have to sit there and rev it at a high rpm until the needle gets nearly verticle. Is that choke related?
-Sometimes when I'm shifting - seems like it's always from first to second - I get a resounding pop through the carbs.
-When I shut it off it always deisels and sometimes I get a really, really resounding pop through the exhaust.

Has anyone rigged up their chokes yet? I know where they are and how they work. I just don't want to open the hood whenever I start it cold.








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    Mikuni drivers. 120-130

    Pearl,

    Contact John Parker at V-Performance. He has the smaller inlet valves and seats meant to be used with a pressurized system. Unless you have changed the valves and seats on your carbs, 2 lbs is 2 lbs too much.

    To prove or disprove: temporarily gravity feed the carbs. I'll wager a nickel that all your fueling problems will disappear.
    --
    Mr. Shannon DeWolfe -- (I've taken to using Mr. because my name tends to mislead folks on the WWW. I am a 51 year old fat man ;-) -- KD5QBL








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    Mikuni drivers. 120-130

    I'm only familiar with mikunis from working on bikes but here goes. The excess fuel symptom needs to be fixed first, all the other issues, dieselling, hard start etc will have to be dealt with after you get the fuel under control. I don"t know what kind of fpr you have but they are very unreliable. In the end I always end up getting a fuel pump the does the good psi. My experience is that if I get the fpr set so that there is no extra fuel about at idle it runs lean at extended high rpm. So,if you want set the fpr up to a pressure that does not push past the valves. If that is not possible and you are sure the psi is low enough ("T" in a pressure gage) you need new float valves. SOme of your othere symptoms ( hard start etc) kind of sound like the fuel is syphoning back towards the fuel tank, simple test park it on a steep slope nose down and see if it persits, or see if your fuel tank drains out through the carbs

    !!!!!CAREFULL!!!!!!!!!











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    Mikuni drivers. 120-130

    Is your 2 psi actually measured or done by the numbers on the regulator?
    The numbers on the regulator are NOT psi!

    And if it actually IS 2 psi and they are still leaking you need new float valves.
    --
    George Downs Bartlesville, Heart of the USA!







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