[C1] Engine sputtering on sharp decline
Thread Starter
Cruising
Joined: Feb 2006
Posts: 13
Likes: 0
Well then, a few things:
Float height and a PRECISE positioning of the float in the bowl is hyper-critical on these carbs so I hope your rebuilder was savvy on those points. There is a "left turn stall" fix that has been a known problem in these carbs for years. Fuel can slosh over into a passage and essentially flood the car to the near stalling point.
Its a simple fix but generally the issue only occurs on left turns but any inclines can exaggerate it...
So, to answer your question, yes the stumbling could easily be a flooding condition, in fact, I would give that a high probability.
Float height and a PRECISE positioning of the float in the bowl is hyper-critical on these carbs so I hope your rebuilder was savvy on those points. There is a "left turn stall" fix that has been a known problem in these carbs for years. Fuel can slosh over into a passage and essentially flood the car to the near stalling point.
Its a simple fix but generally the issue only occurs on left turns but any inclines can exaggerate it...
So, to answer your question, yes the stumbling could easily be a flooding condition, in fact, I would give that a high probability.
Thread Starter
Cruising
Joined: Feb 2006
Posts: 13
Likes: 0
Team Owner
Joined: Aug 2007
Posts: 58,061
Likes: 7,145
Army
Uh...that would be an emphatic NO!
Here is the left turn stall fix - but it may not apply to your situation.
Last pic is one of my carbs with the fix (red circle) - at one point I had 8 WCFBs on cars and as spares and they all had this fix.
A 1/2" of 1/8" OD pipe from Ace Hardware slightly beveled on one end with a jeweler's file for smooth insertion and tapping the piece in the hole slightly is all it takes. I've done it with the carb still on the car at times
Here is the left turn stall fix - but it may not apply to your situation.
Last pic is one of my carbs with the fix (red circle) - at one point I had 8 WCFBs on cars and as spares and they all had this fix.
A 1/2" of 1/8" OD pipe from Ace Hardware slightly beveled on one end with a jeweler's file for smooth insertion and tapping the piece in the hole slightly is all it takes. I've done it with the carb still on the car at times
Last edited by Frankie the Fink; Jul 29, 2016 at 07:30 AM.
Safety Car
Joined: May 2014
Posts: 3,783
Likes: 655
These are all good suggestions, I want to add something for you to think about. On deceleration, engine vacuum is very high so if you have a over exposed transfer slot because of improper throttle blade position at idle vacuum can pull hard on the slot and create a rich condition.
What do the spark plugs look like, that may indicate if the engine is rich.
What do the spark plugs look like, that may indicate if the engine is rich.
Thread Starter
Cruising
Joined: Feb 2006
Posts: 13
Likes: 0
Uh...that would be an emphatic NO!
Here is the left turn stall fix - but it may not apply to your situation.
Last pic is one of my carbs with the fix (red circle) - at one point I had 8 WCFBs on cars and as spares and they all had this fix.
A 1/2" of 1/8" OD pipe from Ace Hardware slightly beveled on one end with a jeweler's file for smooth insertion and tapping the piece in the hole slightly is all it takes. I've done it with the carb still on the car at times
Here is the left turn stall fix - but it may not apply to your situation.
Last pic is one of my carbs with the fix (red circle) - at one point I had 8 WCFBs on cars and as spares and they all had this fix.
A 1/2" of 1/8" OD pipe from Ace Hardware slightly beveled on one end with a jeweler's file for smooth insertion and tapping the piece in the hole slightly is all it takes. I've done it with the carb still on the car at times
Last edited by ASJ1960; Jul 29, 2016 at 12:18 PM.
Team Owner
Joined: Aug 2007
Posts: 58,061
Likes: 7,145
Army
Interesting, and even more interesting fix. That has definitely not been an issue for me; just the very specific sharp decline, when I can't provide a little extra gas because I need to decelerate or stop. Without me force feeding the engine in those situations, it loses RPMs and stalls.
Thread Starter
Cruising
Joined: Feb 2006
Posts: 13
Likes: 0
Well, its about $2 and 35 minutes to install that tube, but, I agree it may not be your problem. I'm not buying fuel starvation though unless a float is hanging up....there is enough in the bowls when decelerating down an incline to run the car for many, many seconds..
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