1979 55HP Chrysler Rough at low rpm

[Burntside Troller]

Idle and 3/4 to WOT are smooth but when first getting under way all the way up to 3/4, she shakes/shudders pretty roughly. Timing issue? Plugs are new. Running 91 octane (non-oxygen) fuel.<br /><br />thanks<br />bside troller

 

[eurolarva]

Re: 1979 55HP Chrysler Rough at low rpm

I would replace the fuel pump diaphram. NAPA part number 18-7806(nine dollars). You could do a rebuild on carb as well NAPA part number 18-7037 (15 bucks). I would switch to 87 octane for the motor. I understand the reasoning for using non oxiginated fuel but these older chryslers dont like the higher octane. Get a can of seafoam and run that like every 5 th tank of gas. What plugs are you using? Champion L82C are the best plugs for the motor. They run about 2 bucks a plug. So Ely Huh. Is the ice off the lakes yet?

 

[Burntside Troller]

Re: 1979 55HP Chrysler Rough at low rpm

Heck ya, ice been off the lakes for a few days now. lol! L82c plugs. I'll order the carb kit and diaphram today and thanks.<br /><br />bside troller