Stock Dual Carb Type 4 Runs On After Key is Off

Carbs & F.I.

Moderators: Sluggo, Amskeptic

Post Reply
User avatar
jonyem
Getting Hooked!
Location: Sequim, Washington
Status: Offline

Stock Dual Carb Type 4 Runs On After Key is Off

Post by jonyem » Mon Jul 22, 2013 7:28 pm

When I stop the bus and turn the key off it runs and sputters for half a second before it stops and everything is quiet.
What do I need to look for?

Jonathan
Late 1973 ASI/Riviera conversion.

User avatar
Amskeptic
IAC "Help Desk"
IAC "Help Desk"
Status: Offline

Re: Engine Runs A Little After Key is Off

Post by Amskeptic » Tue Jul 23, 2013 1:00 am

jonyem wrote:When I stop the bus and turn the key off it runs and sputters for half a second before it stops and everything is quiet.
What do I need to look for?

Jonathan
You need to inform the readership of your current carburetion set-up.

If you have a carburetor (vs fuel injection) does it have an electromagnetic cut-off solenoid?
Make sure it is seated.

"Dieseling" is often an indication of too much heat in the combustion chambers. Carbon can glow like redhot little spark plugs and set off the fuel/air without need of your engine's actual ignition system. This is bad for the engine.

In the meantime while you track this down, do the following mandatory engine protection procedure:
At shut-down, engage 4th gear, foot on the brake, load down the engine by letting out the clutch a bit, turn key to "off". This will help prevent damage.
Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

User avatar
jonyem
Getting Hooked!
Location: Sequim, Washington
Status: Offline

Re: Engine Runs A Little After Key is Off

Post by jonyem » Tue Jul 23, 2013 9:03 am

Dual carb, no cut-off solenoid.
Late 1973 ASI/Riviera conversion.

User avatar
Amskeptic
IAC "Help Desk"
IAC "Help Desk"
Status: Offline

Re: Engine Runs A Little After Key is Off

Post by Amskeptic » Wed Jul 24, 2013 11:50 am

jonyem wrote:Dual carb, no cut-off solenoid.
Let's keep going. What dual carb set-up? Stock? Weber? Dellorto? Kadron?
Colin?
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

User avatar
jonyem
Getting Hooked!
Location: Sequim, Washington
Status: Offline

Re: Engine Runs A Little After Key is Off

Post by jonyem » Wed Jul 24, 2013 12:30 pm

Sorry, they're Stock.
Late 1973 ASI/Riviera conversion.

User avatar
jonyem
Getting Hooked!
Location: Sequim, Washington
Status: Offline

Re: Engine Runs A Little After Key is Off

Post by jonyem » Wed Jul 24, 2013 3:04 pm

I tried backing out the idle adjust half a turn and it's back to normal.
A few days ago I was making carb adjustments and turned it in too much.
Late 1973 ASI/Riviera conversion.

User avatar
Amskeptic
IAC "Help Desk"
IAC "Help Desk"
Status: Offline

Re: Engine Runs A Little After Key is Off

Post by Amskeptic » Thu Jul 25, 2013 10:24 am

jonyem wrote:I tried backing out the idle adjust half a turn and it's back to normal.
A few days ago I was making carb adjustments and turned it in too much.
What is the "idle adjust". We have two mixture screws on the carburetors one mixture and one idle speed screw atop the left carb for the central idling circuit. Now that you do not have spark plugs launching at the ceiling, we could do a day next summer that is able to focus on the magic that is the factory dual carburetor set-up.

Glad you got it dealt with!
Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

User avatar
jonyem
Getting Hooked!
Location: Sequim, Washington
Status: Offline

Re: Stock Dual Carb Type 4 Runs On After Key is Off

Post by jonyem » Thu Jul 25, 2013 12:21 pm

Sorry, I may have my terminology wrong. I'm going to need to upload some photos of my carbs to help me identify what I actually have. Little by little I get something down to the point where I know enough to ask the right questions. Carbs are still on the "I dunno" list.

Otherwise the bus has been running beautifully as of late, and it's been a joy to drive.
I meant to schedule a visit this year but money has been an issue (when isn't it?) and couldn't decide what to tackle this time around. Between now and when the deposits are due next year I'll have both the money for the visit and getting some parts.
Late 1973 ASI/Riviera conversion.

User avatar
Amskeptic
IAC "Help Desk"
IAC "Help Desk"
Status: Offline

Re: Stock Dual Carb Type 4 Runs On After Key is Off

Post by Amskeptic » Fri Jul 26, 2013 11:35 am

jonyem wrote: The bus has been running beautifully as of late, and it's been a joy to drive.
money has been an issue.
Good. You deserve some deposits in the bank of VW karma.

Rustle up couch cushion change, empty your pockets before each wash, raid the kid's piggybank, charge people to look in the bus, throw a bake sale "Help Keep The Legend Alive".
Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

Post Reply