91 Justy dies when warm

1991 SUBARU JUSTY
4 CYL • FWD • MANUAL
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AMWARDELL
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just swapped engine from wrecked 91 justy to another 91 justy same year, same engine. got it running but not quite perfect. had to keep the gas pedal to the floor to start and then slowly, like over 10 minutes, let it my foot off in order to keep it running. it would finally settle to a nice idle, but then die. accidentally put chainsaw oil in gas tank, so ran as much out of the gas tank as i could, replaced pump and filter with the one from the other car. still having the same problems. yesterday it started right up after i swapped a part, not sure what it was, just some tubes that come off the carb into little relays or something, and i adjusted the idle and let it run. it ran for about 10 minutes then died and i couldnt start it without putting my foot to the floor again.
Apr 6, 2011 at 4:44 PM
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FIXITMR
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any way to check fuel pressure? has that got a carb or throttle body?
Apr 6, 2011 at 6:39 PM
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AMWARDELL
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its a carb. i could buy a pressure checker thingy.
Apr 6, 2011 at 6:50 PM
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FIXITMR
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with a carb, exact pressure is not to important. just loosen line at carb and make sure it's working.
Apr 6, 2011 at 11:01 PM
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AMWARDELL
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its getting fuel because it will run at times and not at others. at a certain point in trying to adjust the carb the car would start and rev up and down by itself, with the idle really high. what makes changes in the idle speed like that on a carbureted vehicle? also when i have to have my foot planted for it to start, i can keep it running at redline, then slowly take my foot off and theres a point about an inch from the floor where it just stops getting fuel it seems all of a sudden.
Apr 7, 2011 at 12:00 AM
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AMWARDELL
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there is one vacuum hose thats not connected its the return line from the vacuum canister to the fuel tank i cant find where it connects.
Apr 7, 2011 at 12:01 AM
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FIXITMR
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what do you mean by adjust the carb? take plugs out and see what color the tips are. black=rich brown=good white=lean.
Apr 8, 2011 at 4:44 AM
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AMWARDELL
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they were black so i replaced them and tried resetting it.
Apr 8, 2011 at 3:39 PM
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FIXITMR
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running way to rich, now just got to figure out why. is there a butterfly/plate style choke on carb?
Apr 8, 2011 at 5:03 PM
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AMWARDELL
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im not sure. i went to start the car today and a bunch of gas shot out the exhaust and its filling up the crankcase and spewing out the little hose that goes from the valve cover to the air filter and its all mixed with the oil.
Apr 8, 2011 at 6:55 PM
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FIXITMR
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yikes, sounds you got a real mess on your hands. be nice if you had access to a similar car to check all your connections. i still dont know what you mean by adjust carb? and maybe you got yourself a bad motor? i always like to hear them run before i switch them.
Apr 9, 2011 at 6:02 PM
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AMWARDELL
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i drove the car before i swapped the motors and it ran fine. theres a screw on the back of the carburetor that if you screw in i believe it makes it rich and out makes it lean. it will run on its own if i screw it almost all the way in. do you know where the vapor return line goes? its the vacuum line that connects the vapor canister to the fuel tank, i cant find where it hooks up so its loose. if you had pictures thatd be great, the diagrams dont help.
Apr 9, 2011 at 7:12 PM
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FIXITMR
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if your crankcase is filling with gas you probably have a float not working properly and it's overspilling into intake this would account for too rich. i wonder if that screw is either air adjust or float adjust?
Apr 10, 2011 at 11:03 PM
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AMWARDELL
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ill check the manual and let you know. if it isnt, then should i rebuild the carb?
Apr 10, 2011 at 11:34 PM
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FIXITMR
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but it was working ok before the switchover?
Apr 11, 2011 at 10:27 PM
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AMWARDELL
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yes. and a couple of times it worked fine after, but died after running for about 10 minutes
Apr 11, 2011 at 11:46 PM
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FIXITMR
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what about switching carb from old engine?
Apr 12, 2011 at 3:08 AM
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AMWARDELL
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the old engine is long gone unfortunately
Apr 12, 2011 at 3:25 AM
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FIXITMR
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have you thought to do a search for subaru forums? i'm finding that the older stuff is getting left behind and ignored mostly in many different car types.
Apr 12, 2011 at 4:14 AM
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AMWARDELL
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ive spent HOURS in subaru forums
Apr 12, 2011 at 7:45 AM
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FIXITMR
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so did you determine if the choke is the problem?
Apr 12, 2011 at 8:33 AM
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AMWARDELL
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im pretty sure its not. besides its non adjustable on this car.
Apr 12, 2011 at 4:17 PM
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FIXITMR
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it's automatic in design, right? you can hold it open when cold to see if that helps?
Apr 12, 2011 at 8:59 PM
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AMWARDELL
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i tried that it doesnt help
Apr 12, 2011 at 9:30 PM
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FIXITMR
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i have seen lots of complaints on the net about that carb. i would guess if you got some vac hoses crossed it could mean trouble. i had a sentra with a carb i never did completly get right.
Apr 13, 2011 at 2:46 AM