• Hi Guest!
    You can help ensure that British Car Forum (BCF) continues to provide a great place to engage in the British car hobby! If you find BCF a beneficial community, please consider supporting our efforts with a subscription.
    There are some perks with a member upgrade!
    **Upgrade Now**
    (PS: Subscribers don't see this gawd-aweful banner
Tips
Tips

Run on control

Share this page

Guinn

Guinn

Jedi Warrior
Offline
I like my Weber DCV carb BUT it does want to run on after the ignition is killed. I have a Run On Control valve inside the right fender which has all the wires and tubes except for the tube that would connect to the Zenith-Stromberg if it were installed. Can anyone tell me (pictures, please) how to make this ROC work?

Also, where is the oil pressure switch and what does it look like? My info is that it is on the firewall but I cannot locate it. This is a part of the ROC system.

Feeling dumber than usual,

Guinn /ubbthreads/images/graemlins/confused.gif
 
The oil pressure switch should be on the right side on the shelf of the fire wall. Follow the smaller of the 2 oil lines from the back of the engine block to the firewall and it should be there. ROundish item with a single electrical plug.
 
1969 MGB Run On Control= Shift into third. Foot firmly on brake. No Gas. Drop clutch.
 
The run on control valve applies manifold vacuum to the float bowl of the ZS carb.. If you don't have a vacuum connection on your webber float bowl, you will be out of luck!!!/ubbthreads/images/graemlins/shocked.gif

Basically, it starves the engine of gasoline when it shuts off.
 
Roadstr6, currently I find that a quick "goose" to the gas pedal after turning the ignition off USUALLY kills the engine. Sometimes it needs to be in gear and the clutch dropped.

Alameda, I think you may be right. Can't find a vacuum line to the carb except for Dizzy advance.

Guinn
 
hey guinn, have you had any problem with vapor lock? After i run my B, I have a hard time starting it when the engines hot. I've got the downdraft weber, and am considering switching to dual S.U.'s. Do you have a picture of yours installed? Also, did you install a heat shield?
 
Never had problems with vapor lock, always starts readily. I just got back from a weekend trip but will take a picture and add it in here.

Guinn
 
Run on typically occurs due to two reasons.

1. The mixture too rich.

2. There is carbon buldup in the cylinders which gets very hot and ignites the mixture. Try an Italian tune-up.
 
Back
Top