Troubleshooting
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Cross-Country
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Troubleshooting
I have a 1983 F250 XL with a 300 L6 on my hands. It starts up just fine but cuts out and dies after about a minute if I let it idle or if I give it more than about 50% throttle. I've changed the sparkplugs, cap and rotor. I think that the carb might be bad and is just flooding the engine but I'd like to hear other people's opinions or if they've dealt with the same issue.
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From: Virginia
Does it start right back up? If it just cranks over and over after it stalls, shoot some brake cleaner down the carb and see if it tries to run on that. If it does, you know you have fuel delivery problem.
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Cross-Country
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It starts up after about 30 seconds which makes me think that the carb is flooding the engine and it just needs some time for the gas to evaporate. I've used carb cleaner and some starter fluid and it usually starts up and does the same thing and dies after about a minute.
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Joined: Jan 2001
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From: Virginia
It starts up after about 30 seconds which makes me think that the carb is flooding the engine and it just needs some time for the gas to evaporate. I've used carb cleaner and some starter fluid and it usually starts up and does the same thing and dies after about a minute.
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Cross-Country
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I figured out the issue, the previous owner replaced the dual tank switchover valve and I have it on front because that is the tank that has fuel in it but he put it in backwards so when the switch in the cab is in the rear position, it draws from the front tank.
FTE Legend
Joined: Nov 2015
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From: Angier, NC
Thanks for letting us know what the fix was and not that hard to fix at that as the valve only has 3 ports - 1 out 2 in.
For others the valve should be marked F and R IIRC
With no power to the valve it should draw from the rear tank.
Dave ----
For others the valve should be marked F and R IIRC
With no power to the valve it should draw from the rear tank.
Dave ----
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Cross-Country
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Yeah, felt like kind of an idiot because I didn't even think about the selector switch and my mind went to the Darkside about starting to have to replace a bunch of stuff.
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FTE Legend
Joined: Nov 2015
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From: Angier, NC
You may want to check the valve out a little.
If the motor was running out of fuel running from the wrong tank, then why would it restart after sitting?
I think the valve is not fully seated 1 way or the other and might be pulling from each tank and why it may restart after it runs out of gas?
Or do you think the other tank is that low on fuel it would not keep the carb full?
I have found the valve on Ebay think under FV-1 PN.
The wire hooks up a little different and I think I had to use nuts & bolts to bolt it to the frame other wise hoses hook up and works as it should.
I bough 2 extras at 1 time because the new one I had installed I thought stopped working but was a blown fuse.
My valve has been working going on 3 years now.
Dave ----
If the motor was running out of fuel running from the wrong tank, then why would it restart after sitting?
I think the valve is not fully seated 1 way or the other and might be pulling from each tank and why it may restart after it runs out of gas?
Or do you think the other tank is that low on fuel it would not keep the carb full?
I have found the valve on Ebay think under FV-1 PN.
The wire hooks up a little different and I think I had to use nuts & bolts to bolt it to the frame other wise hoses hook up and works as it should.
I bough 2 extras at 1 time because the new one I had installed I thought stopped working but was a blown fuse.
My valve has been working going on 3 years now.
Dave ----
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Cross-Country
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I think because I was trying to get it to start using some brakleen it was just running off of that but I'm not sure. I know the previous owner just replaced the valve before he sold it to me and I think he just put the hoses on backwards but it runs now. Just have some little tweaks to figure out in the guage cluster now.
Lead Driver
Joined: Nov 2013
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Ooh, well played. Always blame the previous owner!
You may want to play around with the valve a little to make sure it's operating correctly. The 3-port valve is very simple. It is spring-loaded to connect the outlet to one inlet port. When energized with battery power, the internal electromagnet moves the valve so the other inlet port is connected. If the electromagnet has failed, or the fuse is blown, the valve will spring-load to the default position.
Could be the previous owner plumbed the valve correctly but it failed electrically, so it only feeds from the default tank regardless of the switch position. Only early models, the front tank was the default. On later models, the rear tank was default. Not sure exactly when the wiring was changed, but the rear tank is the default on my '84.
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Cross-Country
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I'll for sure take a look at it but the rear tank is still empty because he only just replaced the valve so I have yet to test if putting the switch in the front position will draw from the rear tank.
Lead Driver
Joined: Apr 2002
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When there is no power to the switch I think the valve defaults to the rear tank. That may be part of your issue.
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