been playing with my charcoal cannister on the EA82T which has 4 hoses connected. For LPG reasons I have rerouted the one that feeds to the intake boot after the AFM to feed into my air box post filter (used a tubeless valve tit thru a hole). The other three connect to three metal pipes that run through with the fuel supply and vacuum line tubes. The next I tinkered with was the hose that meets the tube closest to the centre of the block. The other end goes to do a right turn bend down into the inlet manifold at the front below the throttle.
Teed in my vac boost gauge here to see what it gets. Oddly it gets just two or three inches of vac and no more when there is heaps more manifold vacuum ??? And gets all of the boost pressure. If this feeds straight off below throttle blade I do not understand why not all vacuum ?? Maybe it is that I have teed off and not straight onto it leaving cannister out of equation. FSM does not offer any reason. I am looking because I suspect boost gas vapour is getting out of manifold on boost and into cannister and escaping - getting slight ethyl mercaptin smell
anyone know these babies??
maybe the vac is lost to the cannister ??
EA82T emission cannister hook up
The primary function of the charcoal cannister is to scavenge vapour from the fuel tank, and feed it to the manifold when in vacuum conditions.
So one line hooks up to a pipe leading to fuel tank - this pipe is the larger return pipe. (gas/vapour needs more volume).
The purge valve is supposed to be vacuum activated.
My recollection of how I hooked it up on ea82t is scant, sorry.
Its very possible it might have been broken by positive pressure to the purge valve,thus open continuously, however I just thought of that now, and I was driving it for years.
It should probably be done with a purge control solenoid, ECU controlled to open the solenoid whenever vacuum detected, using a carbon canister from any newer vehicle.
The 4-port type is really just for carby engines.
:phey you thought you were finished as with your other thread on EGR, ....yes this should be sorted too.
It can be dangerous I think if vapour pressure builds up - reminds me once of when I sitting at lights, a hot day, and this vehicle infront had a shimmering effect distinctly hovering over the fuel cap and quite alot too, if some smoker happened to pull up next to it - big bang!
So one line hooks up to a pipe leading to fuel tank - this pipe is the larger return pipe. (gas/vapour needs more volume).
The purge valve is supposed to be vacuum activated.
My recollection of how I hooked it up on ea82t is scant, sorry.
Its very possible it might have been broken by positive pressure to the purge valve,thus open continuously, however I just thought of that now, and I was driving it for years.
It should probably be done with a purge control solenoid, ECU controlled to open the solenoid whenever vacuum detected, using a carbon canister from any newer vehicle.
The 4-port type is really just for carby engines.
:phey you thought you were finished as with your other thread on EGR, ....yes this should be sorted too.
It can be dangerous I think if vapour pressure builds up - reminds me once of when I sitting at lights, a hot day, and this vehicle infront had a shimmering effect distinctly hovering over the fuel cap and quite alot too, if some smoker happened to pull up next to it - big bang!
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steptoe
- Master Member
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- Joined: Thu Oct 06, 2005 10:00 am
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further testing and I hook up vac boost gauge directly to pipe from manifold and no T in this time - I get as expected manifold readings. So looks like on vacuum the valve allows vapours from the cannister or just air if no vapours to enter manifold. On boost it looks like the valve closes which is why I got boost readings.
Checked the specs of these things and all EA82s from early are four hoses with exception of the non turb mpfi it has one plugged up so has three hose connections
EDIT: no members online !! I'd better leave too.
Further reading helps with an interest in the topic. I find that the vacuum line at the front of the TB is a control line (much like dizzy vac advance) for the purge valve so does not actually bypass any air or vapour of the AFM or throttle. It doesn't hurt to play with and test to get a better understanding of pollution rubbish stuff that many mechanics have not understood in the past and just plugged up any hose not seeming to have any importance. I now have a better understanding of pollution controls of cars made twenty years ago !! Looks like it is a smaller diameter hose that comes from tank, but not worry about that memory loss going on hey
Checked the specs of these things and all EA82s from early are four hoses with exception of the non turb mpfi it has one plugged up so has three hose connections
EDIT: no members online !! I'd better leave too.
Further reading helps with an interest in the topic. I find that the vacuum line at the front of the TB is a control line (much like dizzy vac advance) for the purge valve so does not actually bypass any air or vapour of the AFM or throttle. It doesn't hurt to play with and test to get a better understanding of pollution rubbish stuff that many mechanics have not understood in the past and just plugged up any hose not seeming to have any importance. I now have a better understanding of pollution controls of cars made twenty years ago !! Looks like it is a smaller diameter hose that comes from tank, but not worry about that memory loss going on hey
just got back from a ocean swim;), and relaxing a bit now as you do at ausubaru:)
Its not once that people have asked what anti-polution shit!:mad: they can remove in the mistaken belief of getting more power.
Now I was just thinking, your using LPG, which doesn't the add on gear already deal with collecting vapour, and the LPG tank is a pressure vessel,
not like a petrol tank, so perhaps carbon canister is redundant in your case?
Can you get a valve that only passes vacuum ?
Its not once that people have asked what anti-polution shit!:mad: they can remove in the mistaken belief of getting more power.
Now I was just thinking, your using LPG, which doesn't the add on gear already deal with collecting vapour, and the LPG tank is a pressure vessel,
not like a petrol tank, so perhaps carbon canister is redundant in your case?
I think your spot on, I do kinda recall smell after boost, so the boost is forcing fumes out from the carbon canister maybe?" wrote:Teed in my vac boost gauge here to see what it gets. Oddly it gets just two or three inches of vac and no more when there is heaps more manifold vacuum ??? And gets all of the boost pressure. If this feeds straight off below throttle blade I do not understand why not all vacuum ?? Maybe it is that I have teed off and not straight onto it leaving cannister out of equation. FSM does not offer any reason. I am looking because I suspect boost gas vapour is getting out of manifold on boost and into cannister and escaping - getting slight ethyl mercaptin smell
Can you get a valve that only passes vacuum ?
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steptoe
- Master Member
- Posts: 11582
- Joined: Thu Oct 06, 2005 10:00 am
- Location: 14 miles outside Gotham City
while a perol tank is in the car and some petrol still in it there is a need for emission control there.
the valve integrated into the top of the cannister seems to be doing its job because I do get a boost reading when T'd in to observe so it looks that it shuts off holding boost pressure from entering cannister and on vacuum it must only control the flow of the other hoses. It does indicate that on normal turbo or efi the cannister does allow air to get to combuston bypasing afm where the air from cannister hose connects to the flexible boot after afm
the valve integrated into the top of the cannister seems to be doing its job because I do get a boost reading when T'd in to observe so it looks that it shuts off holding boost pressure from entering cannister and on vacuum it must only control the flow of the other hoses. It does indicate that on normal turbo or efi the cannister does allow air to get to combuston bypasing afm where the air from cannister hose connects to the flexible boot after afm