85lebaront2 Posted June 21, 2018 Share Posted June 21, 2018 Thought so. In that case you can't just adjust for max vacuum. That's why they introduced the propane method. It is really confusing that they say the trucks above 8500 lbs don't use the propane method, but then they don't give the proper method. Bill - Is there a rule of thumb? Like "Find max vacuum and then lean the mix by 1 turn"? Roughly, when the emission systems first came East, we had a combustion meter and they had to be set to I think it was 15:1 at idle, propane enrichment came later with catalytic converters as you couldn't get a mixture reading through them. To do the mixture setting the Thermactor pumps need to be disconnected and the lines to the head and or manifolds capped so you are reading actual A/F ratio. If it has to be tested, do a fresh oil change and maybe a PCV valve refresh. Damn glad I do not have that crap here! Link to comment Share on other sites More sharing options...
Gary Lewis Posted June 21, 2018 Share Posted June 21, 2018 Roughly, when the emission systems first came East, we had a combustion meter and they had to be set to I think it was 15:1 at idle, propane enrichment came later with catalytic converters as you couldn't get a mixture reading through them. To do the mixture setting the Thermactor pumps need to be disconnected and the lines to the head and or manifolds capped so you are reading actual A/F ratio. If it has to be tested, do a fresh oil change and maybe a PCV valve refresh. Damn glad I do not have that crap here! By "roughly" did you mean my guess of 1 turn lean from max vacuum is close? That was just a wild guess, but I know they had to be very lean to pass. Link to comment Share on other sites More sharing options...
85lebaront2 Posted June 21, 2018 Share Posted June 21, 2018 By "roughly" did you mean my guess of 1 turn lean from max vacuum is close? That was just a wild guess, but I know they had to be very lean to pass. Problem is if it is too lean NOX goes up and those beasts run hot anyway which contributes to it. Unfortunately nothing either of us has found shows the standards for the over 8500 CA requirements. Link to comment Share on other sites More sharing options...
7thSon Posted June 21, 2018 Author Share Posted June 21, 2018 Problem is if it is too lean NOX goes up and those beasts run hot anyway which contributes to it. Unfortunately nothing either of us has found shows the standards for the over 8500 CA requirements.Gonna try bribing the dealer tech with donuts and/or ice cream. Prolly won't be able to do it till beginning of next week (I work next 4 days). I'll let you know how it goes... wish me luck! On Wed, Jun 20, 2018, 8:06 PM 85lebaront2 [via Bullnose Enthusiasts] <redacted_email_address> wrote:   Link to comment Share on other sites More sharing options...
Gary Lewis Posted June 21, 2018 Share Posted June 21, 2018 Good luck! And, let us know how it goes. Link to comment Share on other sites More sharing options...
vjsimone Posted July 12, 2018 Share Posted July 12, 2018 http://www.garysgaragemahal.com/holley-4180c.html Click on "Ford's Service Manual" Link to comment Share on other sites More sharing options...
85lebaront2 Posted July 13, 2018 Share Posted July 13, 2018 http://www.garysgaragemahal.com/holley-4180c.html Click on "Ford's Service Manual" There is still no idle mixture setting procedure. If I have the 1985 or 86 big emission manual I will see if it has anything. I know they are a pain to adjust due to the location on the mixture screws. Link to comment Share on other sites More sharing options...
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