1985 4.9 fuel problem
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1985 4.9 fuel problem
i've already searched for this and couldn't find anything of help. i just bought a 1985 f150 with the 4.9 straight 6. only paid 500 bucks for it. its ran fine all this past week. tonite i was on my way to wendy's and it stalled at a traffic light. i pushed it into a parking lot and tried several times to start it, only to fail. when it stalled i smelled a strong smell of gas. and when i was trying to get it to start again, i smell a very strong gas smell. it turns over, i have all functions, except for starting. the more i try to start it, the more it smells like gas. does any body have any idea's on what is going on? any help would be greatly appreciated, i have to go back to work on monday. 
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i'm not sure if i have spark or not. that was one of the things i was considering. how would it flood? i mean, i'm not pressing the pedal when i'm trying to start it. i'm hoping its the spark or lack there of. i just bought a cap and rotor, plugs and wires today, they are still in the advanced auto bag on the floor. 
i guess in the morning i'll get the wife to take me to it and see if its getting spark. i'm kinda new to this carb thing, i'm used to fuel injected honda's, *flame suit on*. lol.
i guess in the morning i'll get the wife to take me to it and see if its getting spark. i'm kinda new to this carb thing, i'm used to fuel injected honda's, *flame suit on*. lol.
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When the motor turns, the camshaft spins and bumps the fuel pump arm. Even though you aren't touching the gas pedal, the fuel pump is still drawing fuel from the tank to the carb because of the fuel pump arm being pushed down by the camshaft.
One of the big things on these trucks is the ignition box or the pickup coil inside the distributor heating up and shutting the truck off like someone turned off a switch. The ignition components heat up and create resistance and then you get no spark. If you let the system cool off and it starts again, then two things you could look at is either the ignition module on the drivers side fender well, (the little silver box), or the pickup coil inside the distributor.
Either one of those can be taken down to a parts store and tested to see if it's any good or not so you don't throw good money after bad. Both of those parts aren't that expensive if you just decide to get new ones but I'd get them tested if you can.
One of the big things on these trucks is the ignition box or the pickup coil inside the distributor heating up and shutting the truck off like someone turned off a switch. The ignition components heat up and create resistance and then you get no spark. If you let the system cool off and it starts again, then two things you could look at is either the ignition module on the drivers side fender well, (the little silver box), or the pickup coil inside the distributor.
Either one of those can be taken down to a parts store and tested to see if it's any good or not so you don't throw good money after bad. Both of those parts aren't that expensive if you just decide to get new ones but I'd get them tested if you can.
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now the silver box thing i'm sure i can identify. as for the pickup coil in the distributor, will i be able to see that if i take off the distributor cap and the rotor? if so what exactly does it look like? and how difficult is it going to be to get too? since its sitting in the parking lot of a bank, i'm not going to have a great tool selection at my disposal.
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IMO, it's a whole lot easier to just take out the distributor and have it tested. If you've never taken out a distributor, here's how I do it.
I take the distributor cap off and mark on the top of the base of the cap where the rotor is pointing with a sharpie. Then, I draw a line on the distributor shaft and onto the engine block. Then, when you take it out and put it back in, just line up the lines on the distributor shaft to the block and if it's done right, the rotor should be pointing right to the mark on the cap base.
I take the distributor cap off and mark on the top of the base of the cap where the rotor is pointing with a sharpie. Then, I draw a line on the distributor shaft and onto the engine block. Then, when you take it out and put it back in, just line up the lines on the distributor shaft to the block and if it's done right, the rotor should be pointing right to the mark on the cap base.
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mark everything. ok. now when i do that will i still have to re-time the engine? or no. update: i went to the truck this morning and it started right up. now, from what i learned about 4 cyl. if it shuts off that means that it most likely is the pickup module in the distributor. if its ready to take a ****, when it gets hot it stops working, am i right? as far as replacing that, i searched autozone.com and the module is 20 bucks. but my question is would it be a good idea just to replace the whole distributor since i can get those remaned for 45 bucks after core? or just the module will be easier since i would have to re-time the engine after i remove and replace with a new distributor.
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From: Billings Montana
You may have to fine tune the timing even though the marks may line up, but if you get a good timing light, they're only $40-50.
$65 for a distributor and an ignition module isn't a bad deal at all so if you think you should and money allows it, I'd go ahead and buy them both. It's cheap insurance and if both are original in the truck, it may be time to replace them anyway.
$65 for a distributor and an ignition module isn't a bad deal at all so if you think you should and money allows it, I'd go ahead and buy them both. It's cheap insurance and if both are original in the truck, it may be time to replace them anyway.
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a friend of mine is telling me that my choke could be messed up. he said that if it flooded itself that might cause it to shut down. now, if that were to happen how would i fix that? i have noticed in the past that when i drive to work, or back from work, and i would be pulling into my spot, i hit the clutch and the engine continues to run at a higher rpm, almost like my foot is on the gas but its not. if i quickly hit the gas it sometimes idles down, but other times it doesn't could this be a culprit? guess i should have said something about that earlier huh?
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i just changed the module on the side of the distributor and it seems to run the same, i guess next thing is to replace the coil and the pickup in the distributor. it idles and drives fine now. maybe you're right about the choke, i'll look at that too. ummm....what am i looking for? somthing on or near the carburator i'm sure. is there some way to bypass that? or not. thanks again for your help.
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Changing the module won't always change how well it idles or runs, there's too many variables that determine that. With the choke, there's a black circular housing on the side of the carb that you can adjust.
With the engine cold and off, tap the gas pedal to set the choke. Loosen the 3 or 4 screws around the perimeter of the circular housing and move it back until the choke plate opens just a little. That should lean it out a little bit and not cause it to choke out all the time. If you want to, there should be a wire that goes to the choke housing that you can disconnect and disable the choke.
With the engine cold and off, tap the gas pedal to set the choke. Loosen the 3 or 4 screws around the perimeter of the circular housing and move it back until the choke plate opens just a little. That should lean it out a little bit and not cause it to choke out all the time. If you want to, there should be a wire that goes to the choke housing that you can disconnect and disable the choke.
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alrighty then. i think i'm gonna disconnect the wire to just disengage the choke and see how that works. not sure if there's gonna be any ill side effect but anything is less embarassing than stalling at a a red light and not being able to re-start it you know? lol. thanks for your help. rep added. 
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Just be careful when you start messing with the idle on your carb. They can be pretty particular and if you dont really know what your doing it might be better to find someone who does to either do it for you or help you out.
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thats a good idea huh? because i know absolutley nothing about this truck, and i mean nothing, except for what was just told to me in the above posts. lol. now, what will happen if i do disconnect the choke? nothing, something? or will it just not idle correctly when cold?