help with 73 bay fuel vent PO issues

[alman72]

I really would like to get my fuel vent lines back into stock shape. I am missing some parts, and don't know what other parts look like. Let me start with the charcoal can. Looking on the forums, it should be on the top of the engine compartment, but I have a clamp for it on the firewall.

the little bits of tubing that go bad have been replaced, but I don't know what is going on here-

some pics i have seen have the canister here, but different tubing config.


the PO took this off, and plugged it with a sparkplug. when i get all parts in, i will just put it on the nipple. any reason besides missing canister/airfilter that this would be plugged off?

here is a canister i can run thru a vac oven. or run as is. will it work?

and lastly, the posts i have read indicate that the other big line off the canister go into the air cleaner. I think mine is gone. I could not find a pic for a 73.
anyone have a pic of an air cleaner for a 73? or whatever years were the same?

I have this that was aquired in a box of parts, but dont think it is an air cleaner, or even for a bus. Is it an oil bath?

thanks for any help. dont be hard on the grime or funky wire routing. Not me. working on it.

[Wildthings]

It looks like you have a center mount progressive carb, so there is really no system that is an exact fit for your fuel tank ventilation system. The European system of that era just vented the tank into the air cleaner without using a carbon canister and that is the easiest thing to do. You can actually vent it to just outside the air cleaner and it will work pretty well.

To hook up the carbon canister you need to under stand how it works and that its operation is somewhat unique to an air cooled engine. Not particularly hard to do, but you will not be able to have a valve controlling the vapor release from the carbon canister as per the FI rigs.

What do you have in the way of a crankcase ventilation system? A good functioning crankcase ventilation system is important not just to reduce pollution and stink, but to prolong engine life.

[busdaddy]

Here's a solution: https://www.thesamba.com/vw/classifieds/detail.php?id=2161187 , send them to Tim @ Volkzbitz and after there will be no confusion over where to connect stuff and why it runs bad or gobbles gas.
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[Tcash]

Evaporative Emission Control EVAP/Charcoal, Carbon Canister

[xyzzy]

I'll make you a video tomorrow morning when its light out. I have a 73 that has all the stock components. The spark plug in the braided hose looks like the crankcase breather hose that goes from that nipple to the charcoal canister (overhead). The air cleaner you need is the box-filter with the pizza-slice arms shown in the classifieds link for the dual carb setup.
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1973 VW Westfalia 2L hydraulic, dual Solex PDSIT
1987 VW Vanagon Westfalia

[Tcash]

1973-74 Air cleaner
https://www.thesamba.com/vw/forum/album_search.php...t_dir=DESC

[alman72]

[alman72]

[Wildthings]

[alman72]

it has great slope as it goes up to the bottom of the air filter on the center mount carb.
my center mount carb also has a nipple off the back of the manifold that goes to the brake booster. Another thing I will try to confirm tonight.

[Wildthings]

[xyzzy]

Here's the routing for my 73 dual carb.


Link

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1973 VW Westfalia 2L hydraulic, dual Solex PDSIT
1987 VW Vanagon Westfalia

[Abscate]

I think someone didn't completely understand the use of the word 'plug' in spark plug
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[alman72]

thanks Xyzzy. So on the right side of the charcoal canister, where the T comes in on the small nipple, the big nipple is not hooked up to anything?

I am missing my airbox for sure. not sure where to plumb the end off the canister.
with my tubes on the top of the engine bay looking to be in the configuration for the charcoal canister and rubber T to be there like a stock 73, but I have the canister clamp on the firewall like other years stock setup.....maybe PO put in a firewall from a different year?

[alman72]

the braided line plugged off with the sparkplug goes back to the rear of the tin, into a nipple. went under the bus, removed some tin, and damned if I cant find where the other end of the nipple comes out. I did find, however, that the braided hose that used to be on the evasive nipple, has been mated to a new vac line that goes to the manifold under my center mount carb.

[xyzzy]

[alman72]

[SamW]

Not to hi jack this post, but I am having a similar issue. I just bought a '73 and one of the POs removed most of the emissions control and looks like they re-piped some of the central idle control for the brake booster. I am trying to figure out what I need to put back in place or if what the PO did is ok. The fuel vent goes to the carbon canister, but the other side of the canister is blocked off.

Currently I am rebuilding the carbs due to a fuel leak in one of them. It would sort of start, but not hold an idle.

You can see what I have left of the emissions system in the pictures. Any help would be appreciated.

[SGKent]

were it me on an old pre-smog bus I might consider just plugging the evap system off, and using a vented gas cap. One is more likely to end up with a fire from a broken evap system dripping fuel onto the engine than a vented cap causing issues. In addition, if you just put it to the air cleaner, which some do, one must add a flame trap to prevent a backfire from requiring a fire truck to put a fire out. Same for a crankcase breather line plugged to the top of the air cleaner. The CO blowby in the crankcase is very flammable. A flame trap can just be some brass wool stuffed into a big line etc. The breather filter on air cleaners is designed to not only keep dirt out of the engine, but to stop a flame front.

example

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[ol'westy]

Howdy gang,
I'm going through a similar process with my 74 westy. PO removed the charcoal canister, and joined the gas tank vent lines in the roof of the engine compartment to each other instead of into a Tee. Also, oil breather line from crank case vent goes into a nipple in top of air cleaner cover on Weber progressive center mount carb.

A couple questions. I don't think there is a flame trap in the oil breather line. It's joined with a PCV valve that has been drilled out so it is really just a coupler. Can I stuff some brass/copper/bronze wool in there as a flame trap? Should it be fine like wool or coarse like a copper scrub sponge? How tight does it get packed in? Is there a worry a back fire could push the flame trap material into the engine?

Second, I couldn't locate the proper charcoal canister for my bus, but I have a new charcoal canister in the vertical plastic case used on later buses and vanagons that I modified to fit.

My original canister was mounted horizontally to the fire wall. I will mount this one in the same place, but vertically. The modern one has the same three lines, 1 small inlet from gas tank vent tee, 1 large inlet from fan shroud nipple and another large one from the snout outlet. I used a nylon barb adapter to get the wide snout down to 1/2 inch line that I will use with another nipple into the top of the air cleaner cover. Same question about flame trap. How coarse/fine should it be and how tight should I pack it into the hose? Is it better closer to the air cleaner or closer to the charcoal canister?

Anything else I should be worried about? I've changed all my rubber filler hoses and vent lines, but there is still a slight gas smell I'd like to get rid of as well as do my small part to save the ozone layer.

Thanks for any help or advice you can give.