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Discussion Starter · #1 ·
My Uncle gave me his old 1981 Citation 4500 that was sitting in his barn. I put all new gas lines, plugs, filter and cleaned the carb. The problem I have is, it will start up with the primer but then stall right away. It will run if I continue to use the primer or give it a lot of gas, i mean A LOT! When you give it full throttle it will drive but it is barely moving. Every so often if you give it a pull on the primer it will get full throttle but it lasts for a second only. I cleaned the carb a few times now (taken it totally apart). There are no cracks in the intake, nothing in the exhaust. I put in fresh gas too. I am just stumped. I looked online and everything I found said it was the carb, but like I said, I cleaned it out twice now, jets are all good, nothing gunked in it. Any ideas??? I don't want to bring it to a dealer as it is not worth it. This is for my kids to tool around the yard with.
Thanks
 

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did you check the fuel pick up line in the tank, they rot off,, also start it the best you can ,and try to cup your hand over intake on carb to see if it picks up at all,, should be sucking air also,, check for suction on the fuel pump pulse line, might be crank seals dried up try packing some grease on the clutch side to see if there's a difference. you wont be able to do that on the mag side
 

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Discussion Starter · #4 ·
Thank you, I did replace the pick up line, there is plenty of suction and gas going into carb, actually sometimes there is so much gas that it spits out of the air intake (if you take the air box off you can see it spitting). I will check the crank seals today, thanks!
 

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When you cleaned the carb, did you unscrew the pilot jet and air/fuel adjustment screw to clean them? Almost sounds like the adjustment screw needs adjustments. Is that a slide carb or butterfly? Slide carbs had an air screw. (loosen to richen) Butterfly had a fuel screw (tighten to richen).
 

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Try going to 1 turn out on the air screws. Don't be afraid of adjusting it to get good performance. If you get no change when you adjust the air screw, even down to fully seated, it's likely the pilot jet is clogged, or the fuel or air passages to the pilot jet has varnished up. Those passages are very small and it does not take much varnish to create problems.

I have had stubborn carbs that I boiled in hot water to get rid of the build up. That was marginally successful. An ultrasound cleaner may be a better option.
 

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Discussion Starter · #10 ·
OK, I went ahead and adjusted the air screw, it is running better, i am getting more top end throttle out of it. we don't have any snow on the ground to test correctly so i am just raising the track off the ground. The idle adjustment though, i screw it all the way in and it still won't give it enough to keep it from stalling.
Also, there is a 'T' where the gas line also goes to the primer, it is pulling in air there. i am going to go tomorrow to get a new T, not sure if the air in the gas will make a difference or not?
 

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Discussion Starter · #13 ·
Great news, almost.... So I took apart the carb again, put everything back together and started it up. It now runs, idles, all that. BUT... there is no top end. I can drive it around but it seems to only be able to go 1/2 throttle. I don't want to adjust the throttle as i believe i would need to adjust the oil injector side too? Or is it an easy thing to do? There is a little bit of play in the cable but not a lot. I checked the plugs and they look good, just gray on them, so no burning and not too much oil.
 

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Can you get the boots off the back side of carbs
Pin the throttle wide open
Get your finger in there and feel if the slide is flush with top of throat
Adjust the cables so that they both are just flush
 

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Discussion Starter · #15 ·
Ah, what a big difference. I would say at full speed i am around 25 mph, not bad for a 40+ year old sled.
another problem has arisen on my brief ride a few min's ago. I had to go up and down a large hill to get to my field to bring it up to speed. While going up and down the hill the sled stalled. Then it was very VERY hard to get it running again. It would start only at full throttle and just sit there almost not idling for a few min's until it finally got up the RPM's. thoughts on that? maybe a float is sticking? Junk in the tank that is being pulled through (the fuel filter looks clean)?
thanks!
 
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