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Discussion Starter #1
:1zhelp: Hi Guys!! Well this is my first post i am fairly new here..... but have been reading your posts for months. I have recently purchased a 1968 XR7 351W..... WOW what a car!! I love it!! :D When i first turned the ignition on the car, it would idle at around 500 and make it's way up to just under 1000. Well it was coming time for a service but due to i live in an apartment not the ideal situation to be in when you want to work on a car!! I took it to a shop for it's first service and a general tune/check up to see if they could see any problems mechanically that i had missed. (I am a rookie mechanic!!) Well he said everything was fine... they flushed all the engine, radiator, changed filters and plugs... oh and they told me the engine was idling a little high so they changed it.... well i said okay... i thought maybe 800 is a better idle speed?? Well i got in (it was dark and i needed to replace the dash light bulbs) and drove home.... less than a mile. The next morning i turned the car over and i noticed that it was idling at 450!! ARGH!! Due to the fact that i have read many posts here advising an idle of 800-900!! Well even a modern car would struggle at that so i changed the idle speed on the carb...... it is a motorcraft #### so it now steadily idles at 900 approx. Well i thought oh well that's sorted!! :p: WRONG!! When i press the accelerator the engine roars like it should but when it comes back down to idle... it has dropped 200rpm approx..... do it again and the same another 200rpm gone... i can't get it back..... and it eventually stalls or i turn it off!! (I don't like to hear it just die on me!!) Could someone please help!! I have no idea.....
Many thanks

A proud new Cougar owner

Stu

p.s Ignore my user name... i have a windsor...... i was going to buy a cleveland but..... it was sold by the time i got there!! :D
 

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Idle adjustment

68Kitty351C,

When you re-adjusted the idle, was the engine up to normal operating temp? All adjustments should be made at normal operating temp. When the engine is cold, the fast idle cam comes into play. That could account for the reason that after you step on the accel and release that the engine idles falls off, becuase when you step on it you release the fast idle cam. Is it a stock carb? If so, which one? 2100D or 4300? You didn't state whether it's a 4BBL or 2. Warm the engine up to normal operating temp, hit the accel to drop off the Fast idle cam, adjust you normal idle setting where you need it. There should be a fast idle adjusting screw on the opposite side of the carb by the choke thermostae to adjust the fast idle down if its too high. There are people on here that I'm sure are better at this than I, so it's just my .02, but at least its a start.

Good Luck,
Ron
 

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Hi Stu, welcome to the forum.
 

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also what kind of choke do you have?? it sounds like an choke adjustment to me as well. before you start the car, press the gas pedal once. then fire it up, it SHOULD be in fast idle with the choke on. it should idle at about 1500 rpm or so, then would normally fall back down after it either warms up or until you press teh gas again. when i used to start my car in the morning with the old 2bbl ( factory ) carb, it would idle at around 450 - 500 rpm until it warmed up. until i started using the choke. then it would do the fast idle and crap until it warmed up where it would settle to about 700 - 800 rpm. ( 550 in drive ) if its still erratic, there are adjustments to the choke itself, i mean here in Southern Cali, the choke isnt needed all that much. but yeah, it helps. check all that out then see what happens.
 

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Discussion Starter #5
Thanks!!

Thanks for all the information!!! I have just finished work...... i will have a little play with the carb tommorow morning and i'll check the choke!! I'll let you know how i get on!! As for now i think Pizza sounds good!!
Once again really appreciate the help..... :D

Stu
 

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idle should be about 600 warm 1200 cold but warmed up on step 1500 anything more than 650 is hard on brakes trans and fuel mileage
 
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