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Old 06-23-2011, 06:33 PM
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Scrambler won't idle

I have an 82 Scrambler I put back on the road last year. It idled poorly then but now no idle at all. under 1000 rpm it stalls, between 1000 and 2000 rpm it runs rough or won't stay at a steady rpm. Anyone experience this problem let me know what I should be looking for to fix it. Thanks, Mike
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Old 06-24-2011, 03:23 PM
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Re: Scrambler won't idle

'82 you say?? Is that thing carbuerated? If so like I believe it is, than you maybe want to check the idle speed screw, too low and it will stall just like you said. Its located on the side of the carb. Also check the float, they could be outta whack and cause an issue. If that doesn't do anything may want to pull the carb and clean it check it over. Also check the fuel/air systems to make sure its getting both, otherwise stalling would occur. I.E. Fuel filter maybe old/clogged? Air filter clogged up terribly? Also check the PCV valve, common fail on many Jeeps and could cause rough idle and stalls. Valve dumps the old exhaust into the intake for better complete burn/emissions but when failing, it causes terribly inefficient combustion at low rpms and sometimes resulting in stalling. Also things to check always are plugs/wires/distributor etc, maybe timing is off? Im leaning towards a carb issues or the PCV though. GL with the fix.
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Old 06-28-2011, 04:43 PM
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Re: Scrambler won't idle

Hi, I changed the plugs, wires, cap, rotor and ignition module in the distributor. I also changed the air filter, gas filter, fuel pump and rebuilt the carburetor. The idle screw is turned all the way in which should make the engine idle at 1600 rpm or higher but once the choke opens and the choke cam is disengaged the engine drops from 2000 rpm to 0. It runs rough between 1000 and 2000 rpm or sounds like it's gasping for fuel but dies under 1000 rpm. I also replaced the fuel hoses and added a second filter between the fuel tank and fuel pump thinking maybe dirt or water from the tank. Did not think of the PCV valve, will replace that as well. Anything else you can think of that would cause this problem?
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Old 06-28-2011, 09:40 PM
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Re: Scrambler won't idle

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Originally Posted by bronxmike View Post
Hi, I changed the plugs, wires, cap, rotor and ignition module in the distributor. I also changed the air filter, gas filter, fuel pump and rebuilt the carburetor. The idle screw is turned all the way in which should make the engine idle at 1600 rpm or higher but once the choke opens and the choke cam is disengaged the engine drops from 2000 rpm to 0. It runs rough between 1000 and 2000 rpm or sounds like it's gasping for fuel but dies under 1000 rpm. I also replaced the fuel hoses and added a second filter between the fuel tank and fuel pump thinking maybe dirt or water from the tank. Did not think of the PCV valve, will replace that as well. Anything else you can think of that would cause this problem?
hmmm, still sounds like carb issues, like something is gunked up in there restricting flow. Does it run lean like you said, can you smell/see anything? You say that once the choke disengages it stalls so seems like the obvious issue is the engine is too cold for the mixture and need to warm up some more. Provided a helpful link below on carbs and their issues etc etc, somewhat complex actually. I would try to explain but whats the point, its all laid out nicley here already and below is another nice link on the choke, may give some extra insight

http://autos.yahoo.com/maintain/repa...ques072_0.html

http://www.vw-resource.com/automatic_choke.html

So you have started it clearly, so thats one big problem eliminated but you cant keep her idling. When she warms up (assuming you've driven her around a little) will it idle, is this cold only? If you haven't try getting her warm as soon as you get her running if you can.

Assuming you have good fuel pressure? If its the OEM pump (doubt it lol), maybe its taking a crap? Id rule out spark issues but may as well check timing if you have a light just for the heck of it. These problems are always fun to fix haha, you'll get it sorted out sooner or later
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Old 06-29-2011, 10:16 PM
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Re: Scrambler won't idle

Even after it's warmed up it doesn't idle. Hard to check timing if it won't idle. I can try at a rev to see if it's off but I need it to idle for a good check. I will check out the site links and see if there is anything I missed.
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Old 06-30-2011, 12:59 AM
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Re: Scrambler won't idle

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Originally Posted by bronxmike View Post
Even after it's warmed up it doesn't idle. Hard to check timing if it won't idle. I can try at a rev to see if it's off but I need it to idle for a good check. I will check out the site links and see if there is anything I missed.
Cool hopefully something comes of it. Stay at it, im sure youll find it one way or another. I know how not being able to use a vehicle is, sucks but ehh whatta ya gonna do, fix it i guess
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Old 07-05-2011, 09:50 PM
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Re: Scrambler won't idle

I swapped out the carb for a webber carb and it idles better, down around 900 rpm but still rough and goes up and down 1 or 200 rpm. My brother thinks it's a vacume leak so 'i will see if I can find where it may be leaking from.
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Old 07-07-2011, 01:01 PM
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Re: Scrambler won't idle

Quote:
Originally Posted by bronxmike View Post
I swapped out the carb for a webber carb and it idles better, down around 900 rpm but still rough and goes up and down 1 or 200 rpm. My brother thinks it's a vacume leak so 'i will see if I can find where it may be leaking from.
Well glad the new carb made it better, old one must have been out of whack. Have you run it around, does it drive now or still a stalling issue now and again? If it runs overall then Id have to say the carb was the problem so if she drives ok now then thats one major problem gone.

Now if idle is little off vaccum leak sounds like an accurate diagnosis. Check with some start fluid. Spray it at base of carb where seal is and see if idle changes back to normal operating range. If so then its pretty much a vac leak for sure. May need to get new gasket or adpater plate could be loose. Also could be the base of the intake mani has warped or maybe the carb bottom is the suspect. Check with a straightedge if you have one or even just something straight and you can eye it up. Otherwise Id say just clean off surfaces real good, and make sure everything is torqued properly to spec and you should eliminate that vac leak. Also check Just run that little test and you will know right away. Will prob also make sucking type of sound where the source is kinda like youd expect haha. fixing that will def help smooth the idle out but the main thing is you got her running which is good
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