shipmag
Hagler Technology LLC. Aka Shipmag
I have a 74 FJ40 that I want to reinstall the vapor recovery system and charcoal canister. Does anyone have pictures of their vapor system or a diagram I could use to book this system back up?
74 FJ40 fuel vapor line and charcoal canister diagram
- Thread starter shipmag
- Start date
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I am doing the same for my 10/72, not sure if they are the same. My can is mounted to the fender, some years it was on the battery stand. I found these.
This version is mounted to the battery bracket
There is a hard line that runs under the floor from the vapor separator and check valve to the charcoal can. Then another hard line that runs up and across the firewall to the driver side fender.
This version is mounted to the battery bracket
There is a hard line that runs under the floor from the vapor separator and check valve to the charcoal can. Then another hard line that runs up and across the firewall to the driver side fender.
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Then it makes a bend and ties into the intake thru the VSV with a rubber tube.
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shipmag
Hagler Technology LLC. Aka Shipmag
- Thread starter
- #4
Thanks that helps a lot. I want
To put the old soled carb back on but don't want replace the header with the original intake. Don't have the time to match machine intake and exhaust. Any one in north Phoenix I could take a look at your vapor system. Either Thursday or Friday next week?
To put the old soled carb back on but don't want replace the header with the original intake. Don't have the time to match machine intake and exhaust. Any one in north Phoenix I could take a look at your vapor system. Either Thursday or Friday next week?
I think you are correct. Mine was all disconnected and plugged. Then the PO drilled a hole in the gas cap.
In my case the fuel separator, one-way check valve by the passenger b-pillar, charcoal canister, and hardline remained. I still use my 1974 intake, but I’ve got a 76/87 hybrid carb JimC built for me.
I was going to run it through a VSV (activated with a thermostat switch) to a carb port. But all the complaints stopped when I put on an OEM fuel cap and hooked everything up thru the charcoal canister. I also just use ethanol free fuel. I think that helps too.
If your hardline from the check valve to the charcoal canister has been open, I recommend blowing it out with some compressed air. Mud daubers built a nest in mine.
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shipmag
Hagler Technology LLC. Aka Shipmag
- Thread starter
- #8
Thanks for the tips. I'm the original owner and 40 years ago every one wanted to remove the smog stuff. And raved Weber carbs were the
Best. So like an ill informed dumb young owner if looked like Smog stuff I removed. So now I got to put
It back the way it supposed to to be. But not enough time to do it right which is put the original exhaust on and carbs so tomorrow will be discovery time.
Best. So like an ill informed dumb young owner if looked like Smog stuff I removed. So now I got to put
It back the way it supposed to to be. But not enough time to do it right which is put the original exhaust on and carbs so tomorrow will be discovery time.
Just watch out for the tip barbs on the plastic separator. With age they can snap off. One of mine was broken and the fragrance of gasoline was a reminder something was off. When I replaced the fuel tank is only when I’d discovered it, repaired it and now….ideal!
Important:
You can just see the one way check valve in Engineer's first photo in post 11. It's white, tucked behind the fuel fill neck. This is perhaps your key. The check valve just holds "slight" pressure in the fuel tank. Maybe a couple psi? (Edit: looks like .5 psi from Engineer’s post below.) So with the OEM fuel cap (vented, but only one way which lets air into the tank, NOT out), this keeps the fuel system "sealed" while sitting in the garage. So between the cap and the check valve it is essentially a sealed system with no vapors escaping. (Assumption is your fuel supply and return lines are properly hooked up, and no cracks as Knuckle mentioned.)
Once you start driving the fuel starts sloshing around and heating up. This pressure overcomes the check valve and the charcoal canister comes into play.
This is why my fuel vapor smell went away without my having to hook the charcoal canister exit line into the carb. The system seals up quick enough when I park in my garage. If not, then the line should be routed through a VSV.
You will get a slight "whoosh" when opening the fuel cap to refill. If you aren't now, that is a symptom of this system not working.
You can just see the one way check valve in Engineer's first photo in post 11. It's white, tucked behind the fuel fill neck. This is perhaps your key. The check valve just holds "slight" pressure in the fuel tank. Maybe a couple psi? (Edit: looks like .5 psi from Engineer’s post below.) So with the OEM fuel cap (vented, but only one way which lets air into the tank, NOT out), this keeps the fuel system "sealed" while sitting in the garage. So between the cap and the check valve it is essentially a sealed system with no vapors escaping. (Assumption is your fuel supply and return lines are properly hooked up, and no cracks as Knuckle mentioned.)
Once you start driving the fuel starts sloshing around and heating up. This pressure overcomes the check valve and the charcoal canister comes into play.
This is why my fuel vapor smell went away without my having to hook the charcoal canister exit line into the carb. The system seals up quick enough when I park in my garage. If not, then the line should be routed through a VSV.
You will get a slight "whoosh" when opening the fuel cap to refill. If you aren't now, that is a symptom of this system not working.
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A couple vendors on here sell the correct white check valve.
Correct.
My ‘74 valve still works. I have no idea if that’s an anomaly or not. Nor do I have any idea how long it was in service earlier in its life, or if that matters.
I do know that the hardline it connects to was plugged by mud daubers in my case. The fuel tank was making a horrible popping sound as it was over pressuring until I figured it out.
My ‘74 valve still works. I have no idea if that’s an anomaly or not. Nor do I have any idea how long it was in service earlier in its life, or if that matters.
I do know that the hardline it connects to was plugged by mud daubers in my case. The fuel tank was making a horrible popping sound as it was over pressuring until I figured it out.
My ‘75 check valve was also still working fine. I did replace it however with a new one from @ToyotaMatt early last year. You may think that as a small plastic nothing it would be inexpensive… it ain’t!
it doesn't matter
pb4ugo
SILVER Star
Someplace on CCOT's website has a hose routing diagram.
