still getting run on
Thread Starter
Burning Brakes
Joined: Aug 2000
Posts: 751
Likes: 32
From: Woburn,ma ma
still getting run on
A while back I started a thread on this problem of mine, I thought it may have been a return spring. I changed the spring lowered my idle to about 750-800 it still likes to run on after I shut the car off, I checked the float level in the primaries it was fine, however the secondaries float level seems to high, when I take the plug the fuel dribbles out, I cant lower the float. I believe you loosen the nut and turn the screw clockwise to lower but it's all the way in. and still dribbles out.. could this be a problem for run on?
Tech Contributor
Joined: Aug 1999
Posts: 14,380
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From: At my Bar drinking and wrenching in Lafayette Colorado
Originally Posted by madvette74
could this be a problem for run on?
Run on is caused by excessive idle speed at shutdown. GM had this same problem and solved it by installing the anti-dieseling solenoids used in the mid-70s. If you cannot solve the problem by lowering idle speed, you may consider installing an idle solenoid to close the throttle blades after engine shutoff.
Tech Contributor
Joined: Aug 1999
Posts: 14,380
Likes: 6,390
From: At my Bar drinking and wrenching in Lafayette Colorado
Originally Posted by not a '76
msd ignitions can cause run on too.
Tech Contributor
Joined: Aug 1999
Posts: 14,380
Likes: 6,390
From: At my Bar drinking and wrenching in Lafayette Colorado
It can be, since retarded timing will require that the throttle blades be opened more to maintain idle speed. The open throttle blades can induce run-on.
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Drifting
Joined: Dec 2004
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Originally Posted by lars
No.
Run on is caused by excessive idle speed at shutdown. GM had this same problem and solved it by installing the anti-dieseling solenoids used in the mid-70s. If you cannot solve the problem by lowering idle speed, you may consider installing an idle solenoid to close the throttle blades after engine shutoff.
Run on is caused by excessive idle speed at shutdown. GM had this same problem and solved it by installing the anti-dieseling solenoids used in the mid-70s. If you cannot solve the problem by lowering idle speed, you may consider installing an idle solenoid to close the throttle blades after engine shutoff.
Thread Starter
Burning Brakes
Joined: Aug 2000
Posts: 751
Likes: 32
From: Woburn,ma ma
thanks for all the replys.. again I tried lowering the idle, it's now hovers between 700-750 rpm, I no longer have run on.. finally. but I do have an electric fan, not in use. I run at 190 degrees.. but I would like to know about the diode for the msd ignition, because I have that and knew nothing about a diode or where it goe's.. could someone here send me some directions on this?
Thread Starter
Burning Brakes
Joined: Aug 2000
Posts: 751
Likes: 32
From: Woburn,ma ma
well I spoke to soon, I now have my car idle at 600 cant believe I can get it that low.. here's is something I over looked. when I first took my car out this year, I noticed on several occasion that my fuel pressure was over 9psi what reminded me was, when I was driving today and noticed it at 15psi.. I usually shut the pimp off and turn it back on and it fixes it self.. I have the holley blue pump with regulater.. could I have done something to the carb that now makes it leak, so when I shut it off I get the run on? also still could use that info on the diode with the msd..
Racer
Joined: Aug 2005
Posts: 308
Likes: 0
From: Salem MA
the diode instructions are in the papers your MSD box came with.
like the 6a instalation guide.
it amouts to a diode in line with a wire coming off the alternator.
the msd website probably has the instructions somewhere.
like the 6a instalation guide.
it amouts to a diode in line with a wire coming off the alternator.
the msd website probably has the instructions somewhere.