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Old 03-31-2017, 08:37 AM   #1
WarpathEngineering
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Something is odd

I pulled my truck out of it's winter storage yesterday evening and took it for a drive in preparation of taking it to the body shop to get the rear quarter repaired from the jack*ss that backed into me last fall. I had put it away with 2 full tanks of fresh gas w/ Sta-bil and started it up a couple of times over the winter. With several of pumps of the pedal and a fair amount of cranking it started up and I helped it a little bit before it would idle on it's own and then off I went.

I'd say I was 3 or 4 miles from the house and all of a sudden it started to run like crap, spitting and sputtering. I pulled up to a red light with the idea of turning around and heading back home. I looked in the mirror and saw the exhaust pushing out black smoke, idle was rough and down below 500 rpm. I switched tanks. When the light changed I got it into a corner gas stations and left it run while I climbed under the hood. Everything appeared to be where it should have been so I removed the air cleaner lid. The engine seemed to take a gulp of air and calm down a little. The filter was clean, the choke was fully open as was the damper on the cleaner assembly. Not finding anything obvious, I put the lid back on and drove home.

It ran better on the way home but not great and while I had gotten my idle back I noticed a puff of black smoke as I backed it into the drive. Being a new to me truck, I started last spring with new cap, rotor, coil, wires, plugs, oil & filter change, new vacuum hoses & swapped my old carb with one from Guaranteed Carburetor. What I failed to do was do a compression test, check the timing & set the carb which is now on the schedule for tomorrow. Other than that anyone have any suggestions on where to look?
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Old 03-31-2017, 09:42 AM   #2
geezer#99
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Re: Something is odd

Figure out why it's flooding.
You might need to pull the carb apart to check the needle/seat is installed right and that there's no trash in it.
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Old 03-31-2017, 10:38 AM   #3
Tash4
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Re: Something is odd

sounds like carb. when sta-bil was put in if you didnt run it a while it may not have made it to the carb. possibly needle & seat or float. good luck.
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Old 03-31-2017, 01:22 PM   #4
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Re: Something is odd

I would check the float level as well, I had a fuel filter blow apart on me and messed up my carb pretty bad.
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Old 03-31-2017, 02:49 PM   #5
El Dorado Jim
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Re: Something is odd

Quote:
Originally Posted by Tash4 View Post
sounds like carb. when sta-bil was put in if you didnt run it a while it may not have made it to the carb. possibly needle & seat or float. good luck.
x2
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Old 03-31-2017, 09:10 PM   #6
chrismoore701
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Re: Something is odd

I use sea foam. The issues I have with stabil is one. I recall it only has a 1 year shelf life. So use it or loose it. When I used it in my snowmobile I would still pull the carbs and rebuild and noticed little chunks of white sludge almost like rice. Use sea foam ever since and no problems
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Old 03-31-2017, 11:59 PM   #7
rwhit57
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Re: Something is odd

Black smoke is usually carbon. Another guess would be some settlement around the valves or on top of the pistons from sitting and it could have broke it loose once it got a little warm. The float and seat are a possibility but if you dont see any fuel leaking out of the carb I think I'd let it sit and run up to operating temp and then drive it around the block a time or two, staying close to home at first and if it improves venture out aways. My guess is it will clear up. if it does I'd probably throw some new spark plugs in it.
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Old 04-02-2017, 12:14 AM   #8
andyh1956
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Re: Something is odd

Do you have a Q-Jet carb? If you do the well plugs may be leaking, there is a kit to fix this. The power enrichment piston may be stuck in the up position also.
I used Staybil in my grand son's four wheeler after I rebuilt the carb & put it up last year. I just got a NEW CARB installed, the gas tank cleaned out & the gas EAT the screens offa the tank valve! Just say NO to Staybil!
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Old 04-02-2017, 09:09 AM   #9
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Re: Something is odd

Sounds like a bit of crud made it to the needle/seat and caused the carb to flood. If you filled it with the ethanol gas, that stuff attracts water which can cause rust in the steel gas lines if the gas evaporates over time. Can also cause weird corrosion stuff in the carb bowl.

If your exhaust still has the heat riser valve, make sure it isn't stuck closed. That will cause the intake manifold/carb to over heat and can cause a Q-Jet to flood.
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Old 04-02-2017, 05:44 PM   #10
WarpathEngineering
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Re: Something is odd

Well I pulled the truck out again today and things have evened out. I put a vacuum gauge on it and adjusted the mixture screws and reset the idle screw. I do think the carb is flooding a little as I've got gas wetting the manifold just below the choke. I drove it 20 or 30 miles and it ran just fine this time but I think I might have to check the needle valve.
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