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New idle problem

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Old 04-25-2014, 06:54 AM
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Default New idle problem

Uncovered a new issue, not sure where to begin so looking for tips. I was adjusting my idle when I found it. The other day after a ride it was idling high, 1100 or so. I took the carb off since then cleaned it and installed a new enricher cable. When I went for another ride I parked it to reset the idle while it was hot. Had it down to around 850-950 and was going to grab the digital tach I have to check the accuracy and while it was idling it suddenly dropped by about half then sputtered then stalled. If I let it idle a long time it will do this again. Idles fine, adjust it where I want it then it drops randomly sputters then dies. I assume it's stalling due to the low idle it drops to but why would it randomly drop? I don't idle normally once it's warmed up, but I feel like something's off here and it should be corrected before I'm sitting by the roadside
 
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Old 04-25-2014, 07:59 AM
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The VOES my be dropping out, check for vacuum leaks around the VOES hose.

If the hose looks OK, reach in there with a needle nose and pinch of the VOES hose, or plug the port on the carb, set idle up a little and see if it stays idling steady.

If it does, the VOES itself may be faulty, test it with a mighty vac and ohm meter.

Check for manifold leaks while your at it.

If it still drops out, you can try removing the pilot screw and with a air noozle, blow the cicruit out, watch out for the little oring.
 
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Old 04-25-2014, 08:27 AM
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Check for intake manifold leak first.

You could have dirt partially plugging the air passages. Whenever you take off a carb the sediment in the bowl gets stirred up and can cause issues. Whenever removing I'd recommend a complete and thorough cleaning with a rebuild kit.

You could have a torn / worn accelerator pump diaphragm causing an improper air flow / rough idle. A rebuild kit includes this part.
 
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Old 04-25-2014, 11:43 AM
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I'll check for leaks, is the voes the top hose into the carb? I haven't looked that manual yet. I did pull the bowl and clean it up, but it wasn't dirty. Pulled it since it was off for the enricher cable. I also didn't pull apart the accelerator pump. Probably worth mentioning it doesn't like cold starting, give it three twists and I still have to partially crack the throttle to get it to fire, once fired it's fine stays running when cold on enricher
 
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Old 04-26-2014, 02:05 PM
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I checked the voes and need some help. I checked it with a meter with vacuum it turns on per the ohmmeter. Put it back together and it was stalling with the enricher on. I pulled the vacuum line off the carb and it idled right up and was running perfect. If I put my finger over the carb hole it bogs back down and stalls. If I put the hose back on it will either run or die never the same.
 
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Old 04-26-2014, 02:16 PM
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If you pulled the vacuum line off and left the port open to make a vacuum leak and the engine idles up, it's too rich, or just out of adjustment.

Did the VOES hold vacuum?(If you dont have a mightyvac, just suck on the hose and put your tongue on the end of it, see if it holds)

Lightly close pilot screw and open 2.5 turns, set idle screw up about a half turn or so, see if it stays running.
 
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Old 04-26-2014, 02:47 PM
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Originally Posted by Schex3x
If you pulled the vacuum line off and left the port open to make a vacuum leak and the engine idles up, it's too rich, or just out of adjustment.

Did the VOES hold vacuum?(If you dont have a mightyvac, just suck on the hose and put your tongue on the end of it, see if it holds)

Lightly close pilot screw and open 2.5 turns, set idle screw up about a half turn or so, see if it stays running.
With the carb sucking air it ran perfect, idle went up high like it should with the enricher on. I don't have a mightyvac, but I can pick one up. I have one of these that i used, the end fit perfect in the vacuum line, gave it a few pumps and checked with ohmmeter, but I think I did hear it sucking I assumed it was the petcock, but I don't think I'd here it there would I. Thing is sometimes I put the enricher on, hit the button and it idles fine, others it dies and I have to sit there and play with the throttle to keep it going. What I didn't try doing is manually turning the voes on with the vacuum line, it's pretty short, it's hard to get it sticking out any.

https://www.denniskirk.com/282541.sk...FUcV7AodsHQACQ
 

Last edited by br549A1; 04-26-2014 at 02:50 PM.
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Old 04-26-2014, 04:28 PM
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Ok I am suppose to get a 0 right. This is what I get running ohms meter to terminals with a hose to voes
 
Attached Thumbnails New idle problem-image-1696447683.jpg   New idle problem-image-1800239835.jpg  

Last edited by br549A1; 04-26-2014 at 04:36 PM.
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Old 04-26-2014, 08:32 PM
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If it runs right sometimes and doesn't others, check for intake leaks.
 
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Old 04-26-2014, 08:33 PM
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Originally Posted by Owtlaw
If it runs right sometimes and doesn't others, check for intake leaks.
I checked didn't find any. What about the voes ohm reading. Should it be zero?
 


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