Excellent R&D !!
I know it had something to do with the vent lines, but I didn't figure it out.
Thanks for posting that up in that detail !!
Charcoal Canister / LRA Breather Fix
- Thread starter TeCKis300
- Start date
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Excellent R&D !!
I know it had something to do with the vent lines, but I didn't figure it out.
Thanks for posting that up in that detail !!
I have a couple of dumb questions on my comprehension here..
The modification here is:
Add the new filter up high (remove old one)
Run a 5/8" line from the new filter to the charcoal canister
Run a 5/8" line from the charcoal canister to the adapter (5/8" to 3/4")
Attach the adapter to the 3/4" line that goes to the Evap Canister.
Did I get that right?
and then the rest of the hoses are like in this diagram?
I'm not claiming it is correct, but I ran 5/8" between the charcoal filter and the input of that square box (not sure it's purpose) relocated to the fender, and the rest of the 5/8" from the exit of that square box up to a K&N filter up by the filer neck.
- Thread starter
- #44
Simpler than that. What needs addressing is what's highlighted in yellow. I'll add this to the original instructions for clarification.
Charcoal canister filter > 5/8" line > New cone filter
I went I looked at what I had done with the lines as I know I had figured this was the problem area before.
I had plugged the little 1 / 4” opening up at the filler area.
I had “T” tapped the 1 / 4 “ main vent line into the 5 / 8 aux vent line and ran them up to the 5 / 8 opening at the filler area.
I did report what I had done to LRA, that I “T” tapped the vent lines, and the bigger filter, but I was still getting codes occasionally.
I had cut the 3 / 4 “ hose going to the Evap box and extended the 3 / 4 hose up to a 3 / 4 filter and zip tied it off.
I’m not going to gain anything going from a 3 / 4” filter down to a 5 / 8 “ filter.
My tanks both fill slow “first click” at the pump or I have to stick the fuel cap in to hold it open at the correct slow fill amount.
I still get the codes, but it is once a week or sometimes once every 2 weeks. I only get the codes in the mornings after sitting all night, or sitting for several days. I never get the codes driving around or on the many errands I run, stopping the engine and restarting. It is only when sitting over night.
I’m going to check in the mornings, remove the cap and see if there is any pressure. Maybe my codes are from something different? I was thinking maybe the calculation used for a single tank when the EVAP check is done may not be working for the dual tanks, but I'm not sure if those parameters can even be changed?
Please let us know if you still get the codes, as I'm unsure if it is from the setup with the two tanks or something else?
I had plugged the little 1 / 4” opening up at the filler area.
I had “T” tapped the 1 / 4 “ main vent line into the 5 / 8 aux vent line and ran them up to the 5 / 8 opening at the filler area.
I did report what I had done to LRA, that I “T” tapped the vent lines, and the bigger filter, but I was still getting codes occasionally.
I had cut the 3 / 4 “ hose going to the Evap box and extended the 3 / 4 hose up to a 3 / 4 filter and zip tied it off.
I’m not going to gain anything going from a 3 / 4” filter down to a 5 / 8 “ filter.
My tanks both fill slow “first click” at the pump or I have to stick the fuel cap in to hold it open at the correct slow fill amount.
I still get the codes, but it is once a week or sometimes once every 2 weeks. I only get the codes in the mornings after sitting all night, or sitting for several days. I never get the codes driving around or on the many errands I run, stopping the engine and restarting. It is only when sitting over night.
I’m going to check in the mornings, remove the cap and see if there is any pressure. Maybe my codes are from something different? I was thinking maybe the calculation used for a single tank when the EVAP check is done may not be working for the dual tanks, but I'm not sure if those parameters can even be changed?
Please let us know if you still get the codes, as I'm unsure if it is from the setup with the two tanks or something else?
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Sounds like you're getting the codes after an evap cycle is run then. It runs after the truck is off a certain number of hours. That probably means an evap leak.
Thanks,
I was wondering if the evap cycle runs sometimes on startup? I'm not sure how to check when an evap cycle is run, or was run last.
My friend (a good mechanic) who help me install this suggested checking the fuel cap every morning to see if there is any Positive or negative pressure. There should be no pressure. His though was that it may not be releasing the negative pressure when turned off, as this more often happens when the temp cools off at night.
Gone are the days when a smoke test was all that was needed.
Our trucks have a compare type test. The system pulls a vacuum with a known leak in it, and counts how long it takes to lose the vacuum. Then it pulls the vacuum on the evap system and compares. It can then register a code for 'small leak' or 'large leak' based on the comparison.
THere's a nice youtube overview from a mechanic training course I've linked previously somewhere. It is a long video, and not all applies, but might be worth the time investment if you have an ongoing problem
THere's a nice youtube overview from a mechanic training course I've linked previously somewhere. It is a long video, and not all applies, but might be worth the time investment if you have an ongoing problem
Today when I opened the fuel cap before starting the vehicle I did get a whiff of fuel, when normally I do not. So maybe it was under a little pressure?
Then when I started it those codes appeared.
It's been a couple of weeks since i last got them.
I'm not sure how that valve works that releases the pressure when the vehicle is turned off?
Then when I started it those codes appeared.
It's been a couple of weeks since i last got them.
I'm not sure how that valve works that releases the pressure when the vehicle is turned off?
After some issues on a couple trips to high elevations last year, including the auxiliary tank not wanting to transfer because of pressure build up in the main tank, and getting to smell gas on another trip the entire time we were on the trails (along with slow fill ups), I decided to finally swap out the filter and pipe. Here is the tiny filter that I found when I got in there. We do at least one trip a month, generally dusty roads, no wonder it was clogged. Hopefully will get a trip in soon where I can test it out and see if it's fixed.
RET2
SILVER Star
Ever consider a pre-filter fine mesh cover?
RET2
SILVER Star
Ok, Ok I'll say it, pantyhose work great. Not fishnets
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I talked to Ward at LRA about it a month or two ago, and he suggested putting a kids sock over it. This is how it actually sits. I used what was available.
- Thread starter
- #57
More things to complicate the breather.
Recently had my charcoal canister fail due to an internal vacuum switching valve, Vent VSV, corroding.
forum.ih8mud.com
I believe it's due to this aftermarket breather once again. Cruising in rain must have a lot of moister and water droplets kicked up into where the breather is mounted, and over time, enough moisture causes corrosion in the VSV.
Solution is to do a high loop of the breather line and invert the breather mushroom.
A better solution might be to run the breather up to the engine bay. I got lazy and didn't have the hose on hand, so this was my solution.
Recently had my charcoal canister fail due to an internal vacuum switching valve, Vent VSV, corroding.
Anatomy of P0456 - Small Evap Leak
Recently have been getting CEL code P0456 - small evap leak. As the evap system self test is performed at night by the vehicle, usual symptom would be a nice greeting in the morning with flashing CEL, 4LO, TRAC, etc. And the inability to toggle 4LO, CDL, etc., if off-road camping. It...
forum.ih8mud.com
I believe it's due to this aftermarket breather once again. Cruising in rain must have a lot of moister and water droplets kicked up into where the breather is mounted, and over time, enough moisture causes corrosion in the VSV.
Solution is to do a high loop of the breather line and invert the breather mushroom.
A better solution might be to run the breather up to the engine bay. I got lazy and didn't have the hose on hand, so this was my solution.
Could you please tell me what part is this you relocated to the engine bay, is it the Vent VSV and where is that normally located?
It looks like you have it up near the front passenger side of the radiator?
Is this the valve the closes to pressurize the fuel system and opens to release the pressure when fueling?
I relocated the entire canister to fit the oem row sub tank.
Yes, placed by the radiator after moving power steering reservoir.
Yes, placed by the radiator after moving power steering reservoir.