TheSamba.com :: View topic - Charcoal canister hook-up to a 2.0 with dual carbs.

Sun Oct 25, 2009 11:28 pm

Hello folks... first off let me thank all of you who have helped me so much with your posts wether you know it or not. I recently purchased a 78 campmobile that has a 2.0 with the raby "camper special" engine kit. It has dual weber carbs and a non-vacuum advance dizzy. This is my first air cooled vw.

My questions are:
1. I have replaced all the fuel lines and fuel breather lines, tuned and sync'd the carbs, timed the engine, replace almost all of the steering components, and am in the process of replacing the fuel filler piece at the gas cap end. Is there anything else I should look into before I take my family on our first road trip?

2. As i was replacing the fuel breather lines, I noticed that the charcoal canister is hooked up to the breather lines back to the gas tank, but the 90 degree large elbows on the top and bottom are not connected to anything. Is it OK to leave them this way? If not, should I connect the top elbow to the vacuum nipple on one of the carbs to pull gas vapor?

Thanks in advance!

Mon Oct 26, 2009 6:30 am

Welcome and congratulations! Did you build the CS or did it come with the bus?

If the small line to the tee in the top of the engine compartment is already connected you need to find the nipple on the right rear side of the engine tin over cyl #2 and connect it to the canister, then add a hole and fitting into an aircleaner base for the other large line off the canister.

How did you adjust your timing? What method and what spec?

Mon Oct 26, 2009 7:19 am

thanks for the welcome! the CS came with the bus and has quite an extensive write up on the build here on the samba.

i adjusted my timing using a strobe. i manually accelerated the bus until the mechanical advance stopped working and held it at that RPM. i then turned the dizzy until i was getting about 28 degrees BTDC which is what jake raby suggests for the kit.

so the large fitting on the top of the canister goes to an aircleaner and the fitting on the bottom goes to the nipple on the right rear of the engine tin?

thanks again!

Mon Oct 26, 2009 7:37 am

Yes, correct on the plumbing.
Also good to hear you are timing it correctly, some go at it in dangerous directions that could lead to serious engine damage.

So is that Ryan's bus?

Mon Oct 26, 2009 7:59 am

it is ryans bus... and man do i love it!!

Mon Oct 26, 2009 8:16 am

just a few more questions... for now.

busdaddy; when you say add a fitting to an aircleaner base, do you mean just drill a hole and add a fitting? can i do it on the aircleaner top plate? as i said before i have replaced all the breather lines, fuel lines, and am doing the filler neck now. now that the canister will be hooked back up (thanks), is there anything else i can do to eliminate gas smells?

also, as long as i'm typing... does anyone know how the seatbelts are attached for the rear seat on a 78 campmobile? there will soon be (a few days hopefully) another member in our family and i need to add another seat belt. there are two sets of threaded holes on the back wall under the bench seat, but they don't seem to line up with where people would be sitting. if anyone has a picture that would be really helpful.

thanks.

Mon Oct 26, 2009 10:35 am

Yes, drill a hole and add a fitting with a nut on each side, plastic is fine and an elbow may give you even better clearance. As for top or bottom? it's your call, if it's in the base you don't have to disturb it everytime you clean a filter.

There is 2 pairs of holes behind the rear seat and another single one on each fenderwell, the fridge covers it on a late camper so there's only 2 pair that are really useful on the right and middle. Follow the seatbelts to find them.

Mon Oct 26, 2009 10:50 am

thanks again!

Mon Oct 26, 2009 12:02 pm

i have another question... i read a lot about people recharging their charcoal canisters if they are the plastic cylindrical ones, but i havent been able to find how to open one up. mine seems to be sealed. any hints?

thanks,

Wed Nov 04, 2009 5:28 pm

well, thanks for all your help friends... but now i have a new problem. i drilled a port on the right carb's airfilter top and put an elbow fitting to attach the charcoal canister return. (the fuel breather system is now complete), while i was working on this, i replaced the fuel filler elbow as well because of cracking. i got everything back together and went to start her up and she runs... but only on two cylinders. (maybe) is the change in air draw on the carb i drilled the port in enough that i will have to re-sync the carbs? if so, how should i go about doing this?

thanks,

Wed Nov 04, 2009 6:56 pm

Don't go messing with any adjustments yet, try removing both airfilter tops and see if the issue goes away. If it doesn't start looking for a wire that's been knocked off or someting pinched.

Wed Nov 04, 2009 7:17 pm

will do... thanks

Thu Nov 05, 2009 8:35 am

well, i took the filters off the carbs and it seemed to run fine, for a few minutes. but then it started running rough again. i searched for any wires or otherwise i might've bumped during the work but couldn't find any. any other suggestions?

thanks

Thu Nov 05, 2009 9:38 am

UPDATE: i can start the bus fine after it sits for a while and it runs fine for about 3-5 mins, and then starts backfiring and putting and eventually dies. i put an untouched top back on the carb so the system is like it was before i tapped the hole for the fuel breather system. is it possible that because i replaced the filler elbow and all the hoses on the fuel breather system the fuel tank is a "closed" system now (with no air leaks) and that could be causing problems. i'm going to take the gas cap off here in a few minutes and see if it runs longer with it off. any ideas would be greatly appreciated!!

thanks guys!

Thu Nov 05, 2009 10:11 am

Sounds like you are going about this logically, try removing the small hose from the canister and blowing into it, you should be able to blow a while and when you stop it should blow back at you.

Any chance you disturbed some crap in the fuel system?

Thu Nov 05, 2009 10:45 am

thanks busdaddy... i i blew into the canister as you said and it blew back at me. something else i noticed as i was staring sadly into the engine bay as it died this time... after the engine dies, the left carb hisses (for lack of a better term) and the right one does not. is this normal?

thanks again.

Thu Nov 05, 2009 11:17 am

How about if you blow into the line coming from the vapor system? I worded the previous post a little vaguely, the canister shouldn't blow back at you but pass air through to the large ports, Hmmm......

Tried running it with the small hose on the canister disconnected?
The hissing could be a few things, maybe it just happened to stop with some compression in one of those cylinders and the intake valve wasn't fully seated. Maybe the float level is high in that carb or the needle/seat is weak and it's overflowing slightly. Is that the one with the port for the brake booster on it? maybe the check valve is leaking.