Engine miss at 30 MPR
- Thread starter JimT
- Start date
Daves55Sedan
Well-known member
BTW...it's MPH (miles per hour).
Could be that your float is set too low, so that the more gas you use, the closer your float chamber gets to empty, so the engine starts sputtering.
If you have done a carb rebuild, go back and look at the float adjustment instructions that come with the carb rebuild kit. There are a couple different versions of the needle, seat and washer(s) depending upon whose kit you buy, so you must use the instruction sheet from the exact carb kit it came in.
It is very easy to adjust the float on a Ford 8BA, EBU, Holley 2100 or ECG carb (Holley 2110). Just take the top (air horn) portion off and turn upside down to gain access to the float and use the cardboard measuring stick that came with your rebuild kit.
Could be that your float is set too low, so that the more gas you use, the closer your float chamber gets to empty, so the engine starts sputtering.
If you have done a carb rebuild, go back and look at the float adjustment instructions that come with the carb rebuild kit. There are a couple different versions of the needle, seat and washer(s) depending upon whose kit you buy, so you must use the instruction sheet from the exact carb kit it came in.
It is very easy to adjust the float on a Ford 8BA, EBU, Holley 2100 or ECG carb (Holley 2110). Just take the top (air horn) portion off and turn upside down to gain access to the float and use the cardboard measuring stick that came with your rebuild kit.
Merc Cruzer
Well-known member
Sounds like fuel starvation.
54vicky
Well-known member
to confirm fuel starvation when it starts to do that ease off the throttle.do not lift off the throttle but slowly ease off it will allow fuel to fill the bowl if it is the float setting.then slowly ease into it see if it keeps up.another thing you can try if you have a manual choke is pull the choke out slowly while driving when miss starts this will change the air fuel ratio.good luck.there may be a problem elsewhere in the fuel delivery system (hole in fuel line etc)
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dmsfrr
Well-known member
The rubber hose between the fuel line on the frame and pump may be obstructed inside. Age and ethanol can ruin them. Check the output pressure & flow of the fuel pump if you can. (keep a fire extinguisher nearby)
Which carburetor and distributor does the engine have?
If the engine has an original 'Loadomatic' distributor you may not be getting any timing advance. When the rubber diaphragm in the vacuum canister goes bad the timing advance does not work at all.
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Which carburetor and distributor does the engine have?
If the engine has an original 'Loadomatic' distributor you may not be getting any timing advance. When the rubber diaphragm in the vacuum canister goes bad the timing advance does not work at all.
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rotorwrench
Well-known member
I've even seen stuff in a gas tank get sucked over to the stand pipe and block it under acceleration. Any flex line that feeds the fuel pump can either have blockage or even a hole in it. Under suction draw it will leak air into the line.
The jets and main fuel metering passages in the carb may have a problem with blockage to fuel or air vaporization flow. Some of the new power valves don't fit the older carbs well. The accelerator pump has to function correctly. Older carb bodies can get warped or have worn throttle shaft bores due to age and shade tree maintenance. Load-O-Matic spark control has been mentioned but this was a system that utilized the carburetor as part of the system. The ports for venturi suction to operate the system also have to be in correct configuration in order to function the diaphragm in the distributor as designed.
The jets and main fuel metering passages in the carb may have a problem with blockage to fuel or air vaporization flow. Some of the new power valves don't fit the older carbs well. The accelerator pump has to function correctly. Older carb bodies can get warped or have worn throttle shaft bores due to age and shade tree maintenance. Load-O-Matic spark control has been mentioned but this was a system that utilized the carburetor as part of the system. The ports for venturi suction to operate the system also have to be in correct configuration in order to function the diaphragm in the distributor as designed.