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Identity of this junction block

Speedrdr

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Nov 27, 2017
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Paris, MS
While lying on my back under the 77 and trying to track lines…both brake and fuel…I ran across this junction (?) block that appears to be fuel related. There’s a line that travels from this block into the PS of the engine compartment and is attached to nada.
Have I uncovered the “roll over valve” and the lne that connects the an evaporative charcoal canister? I thought this 💩 was going to be easy peasy.

Randy
 

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bronco italiano

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'77 should have vent/overflow behind passenger seat in the quarter panel just behind the door
 

DirtDonk

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The anti rollover valve is hidden behind that little metal shield just ahead of the junction connection.
Do you have dual tanks? Just follow the lines and you’ll probably see that there’s one to each tank.
That’s just a guess though.

But a 77, and even some late 76 models no longer had that collection tank behind the panel in the passenger department. That was outlawed along with gas tanks behind seats and pick up cabs.
77 was the last year for that, but Ford made a running change in 76, on the Broncos at least, as far as I can remember.
That’s when they changed from the round metal canister on the frame rail, to the later model plastic rectangular canister up on the firewall.
Do you still have the charcoal canister under the hood?
 
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Speedrdr

Speedrdr

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Learning Member
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Loc.
Paris, MS
The anti rollover valve is hidden behind that little metal shield just ahead of the junction connection.
Do you have dual tanks? Just follow the lines and you’ll probably see that there’s one to each tank.
That’s just a guess though.
Yes, sir, dual tanks. Have found a line that goes from the aux tank across the bed to the R frame to a T fitting at the rollover (?) valve.

But a 77, and even some late 76 models no longer had that collection tank behind the panel in the passenger department. That was outlawed along with gas tanks behind seats and pick up cabs.
77 was the last year for that, but Ford made a running change in 76, on the Broncos at least, as far as I can remember.
Yep, the panels behind BOTH seats are welded up.
That’s when they changed from the round metal canister on the frame rail, to the later model plastic rectangular canister up on the firewall.
Do you still have the charcoal canister under the hood?
Do not have the canister…just the lonesome line that comes free from the rollover (?) valve continuing up the frame into the engine bay.

Randy
 

904Bronco

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San Martin, CA
Both tanks vent lines are joined together with that "T" before connecting to the roll-over valve mounted on the outboard side of the frame rail.

Then the line runs up to the Charcoal canister in the engine compartment mounted on the firewall
 

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Speedrdr

Speedrdr

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So this block circled in yellow is the rollover valve and the line that exits (2nd pic circled in yellow) goes to my charcoal canister…if I had one, that is.

R
 

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