1948 8n rpm problems

[mbigggbass]

hello to all I have 1948 8n and have put new points ,carb ,plugs,wires,ex manifold coil my problem is the rpms go up an then down real low to the point were it almost dies an then goes up again an then down an dies I set timing on the side like book says I some please help tired of throwing money out thnks

 

[DJ54]

Almost sounds like a fuel restriction back at the tank, or sediment bowl. Ever check for fuel flow to the carb.??

How long will it run, before it acts up..?? With a restriction, it will fill the bowl, then the engine will run for a while, but will use it faster than the restriction will fill the sediment bowl. An engine will rev up when the fuel leans out, then die.

 

[mapper]

This could also be an issue with the governor. I used to have a 48 8N, the governor would sometimes stick a bit, try disconnecting the linkage to the governor and working the rods on it back and forth to loosen them up a bit. Try this before you attempting a rebuild.
The previous post by DJ54 suggests looking at the fuel sediment bowl, you should also know that there is a small filter screen in the fuel line elbow into the carburetor, and another intake screen in the fuel tank as well. I never had problems with the tank screen, but the folks I bought my 8N from had stored it in a shed that also housed a number of rabbits, the carb screen was clogged with rabbit fur. Good luck with finding your problem, at least checking and cleaning fuel screens shouldn't cost much.

 

[mbigggbass]

thanks for replay I have cleaned tank before I put all the stuff on but will check that an I will see if gov is stuck thanks a lot will let u no what happens.

This could also be an issue with the governor. I used to have a 48 8N, the governor would sometimes stick a bit, try disconnecting the linkage to the governor and working the rods on it back and forth to loosen them up a bit. Try this before you attempting a rebuild.
The previous post by DJ54 suggests looking at the fuel sediment bowl, you should also know that there is a small filter screen in the fuel line elbow into the carburetor, and another intake screen in the fuel tank as well. I never had problems with the tank screen, but the folks I bought my 8N from had stored it in a shed that also housed a number of rabbits, the carb screen was clogged with rabbit fur. Good luck with finding your problem, at least checking and cleaning fuel screens shouldn't cost much.