My dad has an 86 f150 351 4v HO that we need some serious help with the carb. It has a new accelerator pump, filter, gaskets. It's a Holly for Motorcraft 4180c I think. We need help in tuning the carb as its running very rich since we replace everything mentioned above. I don't dare take any chances as I don't know much about carbs. Thanks.

 

hook a vac line to an empty port on the carb and attach a vac gauge and then turn the air anf fuel screws all the way in but not tight then back out 1 full turn then slowly adjust both till u get the highest vacuum reading

also if it still seems like its flooding u may want to re jet the carb

and make sure the accelerater pump is adjusted to spec

 

I just talked to my dad and he said the jets have been replaced as well. Is the accelerator pump adjustment the screw and spring on the aperture that actuates the pump (to me its seems right) or is it the set screw above it? Where exactly is the mixture screws? I'm tellin ya, I really don't know carbs!!! gotta pic?

 

ill get u some tomarrow my holly is a 4160 serries but similer ill also see what the gap on the accelerator pump is

they also make this thing i never tryed it it goes inplace of a spark plug n when it runs blue u got a perfect tune.

but i had problems with this damn ethinal it chewed all my gaskets i had to do a full rebuild and swap jets and spent a wile tuning it in to run right

also check ur floats theres a cap on the side of both bowls take them out when the trucks runnin and see if fuel comes out if it does lower ur floats till it barly comes out

but ill have picks of everything tomarrow for u

 

Already adjusted the float level. Did that when we did the gaskets. I have heard about the plug replacement thing to tune it, but they were like $50 I think. Saw it in a jegs. My reference source that was helping us has "fallen of the wagon." I will try to get a vac gauge and try that method. See what happens. This truck has got to get better than 7 mpg. Especially with the low mileage.

 

well u are runnin a 600 cfm carb like i am but mines in an 86 olds cutlass i got a tuned olds 307 motor with a holly 600 cfm4160 carb truedauls no cats and im gettin 10 mpg at the most babying it

 

to adjust the accelerator pump u need to
1. hole the throttle wide open
2.use a feeler gauge, check the clearence between the leaver screw head and pump wile depressing the pump with ur finger it should be 1/64 clearance or .051in or .381mm
3. to make the adjustment hold locknut and turn the screw in to increase n outword to decrees

http://arrc.epnet.com/autoapp/8978/c.../89785g30L.gif this is a diagram for the accelerator pump



this is a pic of my whole carb



this is my accelerator pump spring


this is the mixture screw on the passengers side


this is the mixture screw on the drivers side



hope this helps u

 

I'm not sure as to the cfm of the carb but I did find this in 2hrs of research.
"What makes the Holley 4180 different from its aftermarkoet 4150/4160/1850 cousins is the tamper-proof metering block that makes it virtually impossible to adjust the idle air mixture. Also different are the primary boosters, which are annular discharge to reduce emissions."
Found this on a 5.0 mustang site.
So is there only a screw for the fuel?

 

Double post.

 

the first ling i listed and gave a link to if spacificaly for the 4180c carb

 

on mine theres 2 one on each side u adjust both a little at a time till u get the highest vac.

also u said gaskets were all the little gaskets and diaframs changed because ethinal will eat the old ones.'

like i said i had to compleatly rebuild mine top to bottem all new everything. and it still aint compleatly pefect because of the ethinal the more ethinal in the gas the more hesitation i get the less the better it drives

 

All the gaskets are new. It's basically had a rebuild just a little at a time. We just re did the primary float bowl gasket to to replacing the accelerator pump. I also lapped the accelerator pump housing because it was leaking and wasn't true. Also we replaced the o rings in the cross over tube. Right now nothing leaks. We just need to tune it in. I'll take a look at it when I get off work and check the accel pump gap and find a vac gage.

 

thats one thing good about my 4160 easy adjustments with no emmissions stuff real strait forward