Rough running...

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HowardT64
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Rough running...

Post by HowardT64 »

Hello all :) The Duck Blind is running Very rough all of a sudden. Idles fine but when I put pressure on the accelerator it hesitates badly but catches up. I checked the spark plug wires, they are fine. I should mention that the fuel pump is new. I did have a thought that it could be the fuel filter.

Any of you have thoughts? Comments? Carb is not that old either...could it be a vacuum leak?

Any help would be appreciated :)

Thanks!!
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HowardT64
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Re: Rough running...

Post by HowardT64 »

I should mention that I put 15 bucks worth of gas in her Wednesday, Shell gas...it could be that there was water in the fuel. I did top her off with some gas and a fuel cleaner/booster...
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Cheapthrills
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Re: Rough running...

Post by Cheapthrills »

I would check accelerator pump in carb and check the dizzy advance

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HowardT64
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Re: Rough running...

Post by HowardT64 »

I just had it at the Jeep Shop recently and the Mechanic who did the work knows these Jeeps very well...He never mentioned anything wrong with those things. I will check the fuel filter first..since that is the cheapest. I think putting a glass fuel filter BEFORE the pump would be a good idea, as an early warning issue ...could save the pump as well.

The distributor was nice and tight and the hose was connected. Im still thinking I picked up some bad gas and it has the filter clogged.

Thanks for your input!!
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Cheapthrills
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Re: Rough running...

Post by Cheapthrills »

It was a thought.... I hope you get it figured out

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deckroid
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Re: Rough running...

Post by deckroid »

Every so often, when starting my FSJ, it gives off a fart but it will eventually start and then run rough. I have found a vacuum line behind the carb that has come off it's port. Everytime it farts like that, I pop the hood, put the line back and and it starts right up and runs smooth after that. I don't know what that port is, what it does or what that vacuum line goes to.
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prospector
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Re: Rough running...

Post by prospector »

My immediate thought is vacuum leak, starts and idles, revs fine, right? Put her in gear she starts stumbling, that sounds exactly like a vacuum leak. Check how much vacuum the engine is pulling, should be above 16 inches Hg. If you suspect the fuel filter then it's obviously time to replace it. A clogged fuel filter will kill a mechanical fuel pump because the diaphram is being strained by the inability to draw fuel, like trying to suck ice cream through a soda straw. Fuel filters are cheap and easy to replace, rule of thumb: always buy them two at a time, that way you have no excuses for not changing it out.
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Re: Rough running...

Post by HowardT64 »

Okay...got BOTH of the fuel filters replaced. Still does it. After reading what Prospector and Deckroid posted, going to check for vacuum leaks now. Good news is, I am olny out 6 bucks and some change for the filter that goes on the carb. I have since showered and Am doind for the day because my back cannot take anymore. Ill check for Vac leaks either later today or tomorrow.

Thanks for all the input :)
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prospector
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Re: Rough running...

Post by prospector »

It's going to be an easy fix, but keep your eye s peeled for any vacuum hose that is near the exhaust, and near any metal engine chunk, like the intake or cylinder heads, those hoses are meant to be replaced periodically, so if it looks sketchy, replace it. And buy your vacuum hose by the foot, not by vehicle specific application, that'll cost you a ton. I'd get 8 feet of 1/8" hose, then you'll have some left over.
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Re: Rough running...

Post by HowardT64 »

I went to start her just a bit ago...for for a little then quit...no matter what I did she would not turn over. I waited a sec or tow then tried again...then she fired right up and ran normal!! Could something have been clogging the jets? She is running very nice again, in fact a teensy bit better :)

????***SHRUG****????
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az chip
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Re: Rough running...

Post by az chip »

Probably some trash in the fuel just as you said. Might want to check the carb bowl if you can.
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Re: Rough running...

Post by HowardT64 »

Not sure how I could do that...besides II have put my back through enough the last couple of days.. :(
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letank
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Re: Rough running...

Post by letank »

HowardT64 wrote:I went to start her just a bit ago...for for a little then quit...no matter what I did she would not turn over. I waited a sec or tow then tried again...then she fired right up and ran normal!! Could something have been clogging the jets? She is running very nice again, in fact a teensy bit better :)

????***SHRUG****????
planets positionning... alien spacecraft... kidding apart, a bit of water settling in the bottom of the bowl, we have ethanol in gas that tend to trap moisture and wreck havoc after a while... put some gas dryer before you put gas in the tank next time

https://www.youtube.com/watch?v=ZacFsTeAt5U
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HowardT64
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Re: Rough running...

Post by HowardT64 »

Some heet sounds like the ticket thanks :)
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KJ Ryu
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Re: Rough running...

Post by KJ Ryu »

I rebuilt my carb two years ago. Run only ethanol-free from one store. But, the tank is original and some crap gets through. Had issues about a month ago, found sediment in the bowl, cleaned it and the jets/passages under them, etc. Carbs are not that complicated to work on. Do some research and you'll be pleasantly surprised with what you can do, while sitting in a comfortable chair, to boot!
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HowardT64
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Re: Rough running...

Post by HowardT64 »

I have rebuilt carbs before....just in my present state I am VERY limited on what I can do. I am scheduled for back surgery on the 19th of June. Hopefully after that I can devote some time into working on my wag:) If the carb continues to be an issue, Ill pull it...for now I will leave it alone. Heck IM lucky if I put 50 miles on it in a month. Mostly because I stay home a lot.
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musicmaster
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Re: Rough running...

Post by musicmaster »

Ethanol is what killed the 318 in my 69 Dodge. Thankfully most gas stations sell ethanol free gas now.


My jeep ran like crap for a while, turns out there was an exposed vacuum port on the intake. I put a cap on it and its great now! Fires up the first time even in the cold.

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letank
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Re: Rough running...

Post by letank »

musicmaster wrote:Ethanol is what killed the 318 in my 69 Dodge. Thankfully most gas stations sell ethanol free gas now.


My jeep ran like crap for a while, turns out there was an exposed vacuum port on the intake. I put a cap on it and its great now! Fires up the first time even in the cold.

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Most.... please pass the stations in Reno, or add to the list, one in Reno, in Carson, Winemucca...

http://www.pure-gas.org/index.jsp?stateprov=NV

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