I had my truck, 1987 F150 302EFI, parked pointing downhill for a couple of weeks, walked outside the other day and smelled gas. I popped the hood and saw that gas was coming out of the evaporative charcoal canister. I had a hard time starting the truck, smelled flooded, but once I got it going and on a level surface it ran like a champ. Is the charcoal canister ruined? Do I need to replace it? Do you ever need to replace it?

Thanks,

Longneck

 

If the charcoal canister gets flooded, I believe its ruined. You do not have to replace it, but theris something you have to do to the vacuum line to the tank, I belive all you do is stick a plug in it. (block it off). The venting then happens from the gas cap.

any body else have better info?

 

Thanks Fisin1976,
If nobody else has any ideas I will try and do a little more research on it. I'm worried the carbon will fuse together and wont be able to pull a vaccum anymore.

Longneck

 

it would be best to replace the canister it does serve to vent the fuel tank safely. and you should investigate why the fuel system is leaking raw fuel and not vapor in your vent line(s)

 

Fuel vapor in the fuel tank is vented to the carbon canister through the vapor valve assembly, "Fuel Tank Vapor Orifice and Rollover Valve Assembly". The valve is mounted in a rubber grommet at a central location in the upper surface of the fuel tank. A vapor space between the fuel level and the tank upper surface is combined with a small orifice and float shut-off valve in the vapor valve assembly to prevent liquid fuel from passing to the carbon canister.

It sounds as though you either had a 3/4 or more tank of gas and that kept the valve open enough to "pass the gas" at that steep of an angle. Or the valve may simply be stuck open. Either way, the can should be replaced.

 

This reminds me, I pulled my codes the other day and it read "canister purge solonoid circuit fairure". Anyone have an idea what this means? I looked for the solonoid, which I believe is supposed to be right in the vac line from the charcoal canister, but I couldn't find any electrical wires going to anything that could let the computer know about it.

 

I don't have one either, but I don't remember there being a pin location for one in the computer. I was looking for one for the mass-air swap I'm doing, and fordpartsonline.com didn't list one for the 302 for all the years I checked. The Haynes manual says that all vehicles with EFI have a purge valve. NAPA online lists 2 for an 87 with 302, which should be pretty similar to a 90. I need to find one that works so I can get everything connected to the new computer properly. I thought that since I had an 87, they didn't add a purge valve until later editions of EFI, but apparantly they forgot to put them on the 302's. If anyone else knows more, please post.

 

I had a 87 300-6 efi that did not have any purge valve, the vacuum was controlled by the TB. Same way on my '88 351w efi, no purge soleniod. just vacuum lines from the tank to the canister, canister to a 'Y', 'Y' to 2 places on the TB. Thats it. Couldn't tell you about 302's. There were more of those made than either of the other gas engines. Could have been one of those deals with EPA. You know, make your best selling models comply, and we will let you sell the rest that don't comply. Something like that.

 

Yeah, I had a full tank and it was parked on a pretty steep incline. Thanks for the comments, I will start calling around today and see how much a new canister is and who has one.

Thanks,

Longneck