ECS System

larry & kaye kepple

New member
Jan 4, 1999
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[Admin note - Bounced as a "nonmember" submission. Larry, I think the
correct address is "snowcrest.net" Patrick]

Some questions on the ECS system after reading the manual.

1. During filling the gas tank what keeps the fuel vapors from simply
coming from the tank back through the fill vent hose? It seems to me
only part of the vapors would be forced into the carbon cannister
through the separate vent hoses.

2. How important is it to keep this system in operation? Should I
replace the carbon cannister?

3. I see a kink in one ECS vent hose near the fuel/vapor separator. If
this line is shut off what problems might occur?

4. During over filling of the gas tanks I noticed a leak near the frame
behind the fuel/vapor separator. I suspect this is a leak in the ECS
vent hose. Any comments appreciated.

Larry Kepple 73 26'
 
Larry,
My guess is that your rubber hoses might be original or may never have
been replaced. I know most owners have had their hoses on the fuel fill
and vent system replaced at least once in its lifetime. If you decide
to replace be sure to use hose that is marked for FUEL use. This hose
will stand up to the newer fuel that are available. As for question 1
nothing keeps the vapors from exiting the fuel fill area, that is the
tank vent during filling. The canisters can be found at most wrecking
yards in full size early 80 GM cars. As for question 3&4 I would
replace the hoses.

J.R. Wright

>
> [Admin note - Bounced as a "nonmember" submission. Larry, I think the
> correct address is "snowcrest.net" Patrick]
>
> Some questions on the ECS system after reading the manual.
>
> 1. During filling the gas tank what keeps the fuel vapors from simply
> coming from the tank back through the fill vent hose? It seems to me
> only part of the vapors would be forced into the carbon cannister
> through the separate vent hoses.
>
> 2. How important is it to keep this system in operation? Should I
> replace the carbon cannister?
>
> 3. I see a kink in one ECS vent hose near the fuel/vapor separator. If
> this line is shut off what problems might occur?
>
> 4. During over filling of the gas tanks I noticed a leak near the frame
> behind the fuel/vapor separator. I suspect this is a leak in the ECS
> vent hose. Any comments appreciated.
>
> Larry Kepple 73 26'
 
Talked to Bob Lamy about the cannister. He said it was not that
important. I had a problem with the vacuum and it was disconnected in
the process. No problem says Bob. So, in my case I am not going to
worry about it.
Al
 
[Admin note - bounced as a "nonmember submission". Bad "From" header.
Patrick]

While looking for a gas leak in the vent piping near the fuel/vapor
valve I got carried away with the air pressure durig a test and broke
the the plastic fuel/vapor valve. The good news is that Cinnabar now has
these in stock. The bad news is that they cost $140
but I bought it anyway.

Some previous owner installed transmission cooler hose for the various
fuel vent hoses. The outside is checked pretty bad but the inside looks
OK. I found one leak where it rubbed against the frame. I don't want to
replace these hoses because I would have to drop the tanks. Anybody know
if transmission cooler hose will hold up to gas fumes?
 
Rick,
I, too, attempt to do all I can to minimize the impact my activities
have on the environment.
Having said that, I would remind us all that, for instance, Mt.
Pinatubo hurled multiples of ALL THE sulfur and carbon compounds into the
atmosphere than mankind has produced throughout all recorded history.
Not to worry, however. Algore and his clones will shortly introduce
legislation making such eruptions ILLEGAL! And as an added precaution, they
are working on GIANT charcoal cannisters for every volcano so bold and
insensitive to the environment as to erupt in violation of this new statute.
(This, of course, explains the scarcity of charcoal cannisters for GMCs.)
The total area of these new cannisters is almost precisely the same as the
surface of the earth, leaving -- except for a small square area on the
Potomac River -- no room for humans, effectively solving BOTH "problems."
Can anyone see some hidden agenda in our anointed would-be masters'
making "the environment" a virtual religion, the precepts of which are
violated by its "subjects" at the peril of draconian penalties?
Can you say "CONTROL?"
(Sorry for the rant. Must have caught "Arch Syndrome" from his recent post.
:-))

Dick 75 PB on Atlanta

>
>> Some questions on the ECS system after reading the manual.
>>
>> 1. During filling the gas tank what keeps the fuel vapors from simply
>> coming from the tank back through the fill vent hose? It seems to me
>> only part of the vapors would be forced into the carbon cannister
>> through the separate vent hoses.
>
>Larry,
> When filling the tank, the majority of fumes go out into the air. That's
>why you see the unweildy "vapor recovery" nozzles at gas stations in the
>northeast and California these days. BTW, the EPA has decreed that soon all
>new cars must have giant-sized charcoal cannisters to adsorb ALL that vapor,
>rather than retrofit any more gas stations. This apparatus will take up 2 or
>3 cubic feet of space, slightly increase fire risk, and cost you, oh, mebbe
>another $100 - $200 on your new car. Be that as it may, the majority of
>unburned hydrocarbon fumes emitted from the fuel tank(s) are from simple
>evaporation, especially on hot days or altitude/temperature changes. These
>emissions, our conventional charcoal cannisters trap quite nicely, if they
>work.
>
>> 2. How important is it to keep this system in operation? Should I
>> replace the carbon cannister?
>
> Despite my rant above, any time I can do my part for cleaner air for a
>reasonable cost, I am glad to do so. On that basis alone I would say keep it
>working. Now charcoal cannisters lose some effectiveness over time (although
>heat tends to rejuvenate them, so we may finally have a GOOD effect of our
>toasty engine compartments). Most manufacturers recommended replacement
>anywhere from 50,000 to 100,0000 miles, but I've yet to meet anyone who ever
>did it. Even finding replacements may be difficult in some areas. I would
>say replace the cannister filter if dirty or deterioriated, replace the
>cannister if damaged, and replace it for good measure after weighing its cost
>against the weight of your guilt, if any. ;-) One additional thought is
>that this vent system maintains a slight positive pressure in the gas tanks.
>This ensures that all fumes get routed to the charcoal cannister, and the
>pressure reduces the total evaporation. Most important to us, that positive
>pressure (only a few inches H2O) significantly reduces vapor lock in hot
>weather.
>
>> 3. I see a kink in one ECS vent hose near the fuel/vapor separator. If
>> this line is shut off what problems might occur?
>
> Well, may I suggest fuel starvation, vapor lock, ballooned or collapsed
>gas tank(s), for starters. Replace it.
>
>> 4. During over filling of the gas tanks I noticed a leak near the frame
>> behind the fuel/vapor separator. I suspect this is a leak in the ECS
>> vent hose. Any comments appreciated.
>
> As the saying goes, "Git on down there and check it out!"
>>
>> Larry Kepple 73 26'
>
>
>HTH.
>
>Rick Staples
>'75 Eleganza
>Louisville, CO
>
 
[Admin note - Bounced due to bad "From" header. Patrick]

To Rick Staples and others. Thanks for the comprehensive description of
the ECS. But this generates another question. How does the gas vent
system operate under a positive pressure. The carb. is drawing vac. on
the carbon cannister at about 3 plus inches of merc. I would think that
the vent system which is also connected to the carbon cannister is
seeing at least a little of this vacuum, but I don't understand the
configuration of piping inside the cannister. I understand air is drawn
through the bottom of the cannister and is mixed with the vent gas ,
right? But I expected to see a small vac. back at fuel/vapor separator
valve with engine running and didn't. But due to routing of vent piping
with a sag with gas in it I didn't think the vac. was enough to over
come the few inches of gas in the sag. In summary I don't understand
where the system gets a positive pressure.
 
>


Rick, add clairvoyance to your list of talents. I just send my email
"ECS Again" and then checked my mail. Gotta learn to do it the other
way around.

Thanks!
Patrick
- --
Patrick Flowers
Mailto:patrick

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