New EVAP hoses, but how does it all go?

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Deathacus

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Hey there! Gosh, I hate starting a whole thread for such a silly question. My '94 MTX; I ain't the first guy to work on her. I am replacing some vacuum lines under the hood because dry rot is a thing. I don't know which way the purge valve is supposed to go, if direction matters, or how to test if it even still works. Also the reducer. The little red plastic one.
On to the lines themselves, going to the canister. What size are they? I brought them into work to match them up, looks like maybe 7/16? Unless they are just stretched out where the barbs are. Curious, they look like the same vac lines that run everywhere else. Wouldn't an fuel vapor tank need, ya know, fuel line?

And not really a question but anybody have experience with SHOsource's vacuum kit? I just got the firewall kit and the reducer is WAYYY to big, and not brass as advertised, plus the fuel regulator line tore already.

Ugh, since I'm already going ocd on this I'll ask: Near the TB, is the evap hose supposed to go over, or under the PCV hose? And how 'bout the ignition coil plug? (I know this one is just aesthetics, but like, just play along)

Meh, maybe this was worth a thread
 
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zoomlater

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Hey there! Gosh, I hate starting a whole thread for such a silly question. My '94 MTX; I ain't the first guy to work on her. I am replacing some vacuum lines under the hood because dry rot is a thing. I don't know which way the purge valve is supposed to go, if direction matters, or how to test if it even still works. Also the reducer. The little red plastic one.
On to the lines themselves, going to the canister. What size are they? I brought them into work to match them up, looks like maybe 7/16? Unless they are just stretched out where the barbs are. Curious, they look like the same vac lines that run everywhere else. Wouldn't an fuel vapor tank need, ya know, fuel line?

And not really a question but anybody have experience with SHOsource's vacuum kit? I just got the firewall kit and the reducer is WAYYY to big, and not brass as advertised, plus the fuel regulator line tore already.

Ugh, since I'm already going ocd on this I'll ask: Near the TB, is the evap hose supposed to go over, or under the PCV hose? And how 'bout the ignition coil plug? (I know this one is just aesthetics, but like, just play along)

Meh, maybe this was worth a thread
go the bottom of the link below and look for the SHO Engine Book, it may have the exploded view you need. Or you can contact Shosource and ask them

 

Greg Corcoran

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I am replacing some vacuum lines under the hood because dry rot is a thing. I don't know which way the purge valve is supposed to go, if direction matters, or how to test if it even still works. Also the reducer. The little red plastic one.
On to the lines themselves, going to the canister. What size are they? I brought them into work to match them up, looks like maybe 7/16? Unless they are just stretched out where the barbs are. Curious, they look like the same vac lines that run everywhere

Ugh, since I'm already going ocd on this I'll ask: Near the TB, is the evap hose supposed to go over, or under the PCV hose? And how 'bout the ignition coil plug? (I know this one is just aesthetics, but like, just play along)
Hey there! Gosh, I hate starting a whole thread for such a silly question. My '94 MTX; I ain't the first guy to work on her. I am replacing some vacuum lines under the hood because dry rot is a thing. I don't know which way the purge valve is supposed to go, if direction matters, or how to test if it even still works. Also the reducer. The little red plastic one.
On to the lines themselves, going to the canister. What size are they? I brought them into work to match them up, looks like maybe 7/16? Unless they are just stretched out where the barbs are. Curious, they look like the same vac lines that run everywhere else. Wouldn't an fuel vapor tank need, ya know, fuel line?

And not really a question but anybody have experience with SHOsource's vacuum kit? I just got the firewall kit and the reducer is WAYYY to big, and not brass as advertised, plus the fuel regulator line tore already.

Ugh, since I'm already going ocd on this I'll ask: Near the TB, is the evap hose supposed to go over, or under the PCV hose? And how 'bout the ignition coil plug? (I know this one is just aesthetics, but like, just play along)

Meh, maybe this was worth a thread
The evap hose goes under both of those on its way to the intake. The valve doesn’t seem to be marked, but I noted the side towards the intake holds vacuum with the valve unplugged. The side to the canister will weep a bit of vacuum. You need a vacuum pump/gauge for that.
Mine evap vacuum lines were soft, almost mushy at the T under the radiator, and must of the way up to the valve. They were not fuel line rubber, just regular vacuum hose. Mine is a ‘95 MTX.
 

Deathacus

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Thanks for that Greg! I took some parts into work today to try and figure it all out. I'm pretty sure the lines comming off the canister are 7/16. And the valve actually does point out which side goes toward the engine. It is stamped on the plastic T bit. Looking at the sticker with the part number, fittings up, the right hand side should go to the intake, the left hand down to the T fitting in the vapor line. And shosource def sent the wrong fittings so imma have to get on him about that. And the guy before me had some kinda weird patch job so that's all back to normal now.
 
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zak

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Hi - just to the drivers side of the IAC (idle air control valve, or ISC in the SHO engine book referenced above), in between the ISC and the plenum casting, there is a vacuum line that connects and runs forward, over (or maybe under) the intake, to a solenoid valve. After that the line continues on - need to know where that is supposed to go? I think its some kind of fuel vapor recovery system but am not seeing the canister like on one of my older Fords.

Thank you to zoomlater for maintaining that Dropbox, owe you a beer of I make it to the northwest some day
 

zoomlater

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Hi - just to the drivers side of the IAC (idle air control valve, or ISC in the SHO engine book referenced above), in between the ISC and the plenum casting, there is a vacuum line that connects and runs forward, over (or maybe under) the intake, to a solenoid valve. After that the line continues on - need to know where that is supposed to go? I think its some kind of fuel vapor recovery system but am not seeing the canister like on one of my older Fords.

Thank you to zoomlater for maintaining that Dropbox, owe you a beer of I make it to the northwest some day
Actually the dropbox belongs to itwonder
we should all be thankful that its available
 

zak

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Can anyone confirm that the line from the charcoal canister purge solenoid runs straight down to a T fitting on a line that runs horizontally along the top of the lower radiator support? I will have a picture in a little bit. I believe this line runs from the charcoal canister to the T and then across the radiator support and somehow back along with the fuel lines to the top of the tank. e.g. only one maybe 3/8 line to the canister and then quarter inch or smaller back to the top of the tank.
 
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Deathacus

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Yes, from the canister under the fender, to a T under the rad. One end from there goes up to a reducer, then the solenoid, which just dangles there for some reason. The other end of the t, the straight part, keeps going but I havn't raced it all the way to the tank to know what all is going on on that end.
 
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