[xj] Resent: AFM and low idle when A/C on 1980 Ser III 4.2

Listers,
Two questions that you will no doubt find basic. On my AFM there is a
screw recessed in the block. It is readily available from the top. What is
its purpose? I see a lot of info in the archives on the idle speed screw
(which you really have to work to find). Is this the idle mixture screw that
I shouldn’t mess with or something else entirely?
The next question is about my idle when I turn on the A/C. It drags the
engine down to where it will not idle. I think I saw a vague reference to
this symptom being associated with a vacuum problem. I am working on
replacing all the vacuum hoses (Vilis, not as simple as you lead me to
believe : )
but have not hit on it yet it seems.
She is running (and feeling better) after the Ignition module repair, a new
power steering pump, an idler bearing replacement on the A/C compressor,
(some) new vacuum lines, a cooling fan replacement (I went with a 16"
Imperial electric with a thermostatic control), a radiator repair and
cleaning, new coolant, and a water pump removal and reinstallation (it wasn’t
bad like I thought … duh), a new O2 sensor, and belts.
I am paying my dues for having a relatively trouble free 1 1/2 years of
everyday use after she had sat uncovered and unused in my father-in-laws yard
for a long time. I plan to write up a submission got the Genesis project if
and when I ever get a break from repairs.

BTW, I decided that yellow was not appropriate for the fan blades so I have
decided to paint everything that spins, twirls, or otherwise moves bright
green and all the braking system parts red (green for go, red for stop…)

Sorry for rambling.

Bruce "Hoon"aday
1980 Ser III 4.2L
1959 Plymouth Fury
1991 Ford E-150 Custom Van===================================================
The archives and FAQ will answer many queries on the XJ series…
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On my AFM there is a
screw recessed in the block. Is this the idle mixture screw that
I shouldn’t mess with or something else entirely?

Yup, that’s the mixture screw that you shouldn’t mess with. But most of us
do anyway…in for richer, out for leaner.

The next question is about my idle when I turn on the A/C. It drags the
engine down to where it will not idle. I think I saw a vague reference to
this symptom being associated with a vacuum problem. I am working on
replacing all the vacuum hoses

Could be a number of things, including, as you say, a vacuum problem
creating a “lean” condition. Also, what is your idle speed ? If it’s too
low it won’t carry the load of having the AC on. If yours is like most, you
won’t be able to adjust the idle speed or mixture before fixing ALL vacuum
leaks and removing the air distribution valve to clean all the gunk residing
therein.
This one sounds interesting so keep us posted !

Doug DwyerFrom: BHornaday@aol.com

===================================================
The archives and FAQ will answer many queries on the XJ series…
FAQs: http://www.jag-lovers.org/xjlovers/xjfaq/xjfaq.html
Archives: http://www.jag-lovers.org/lists/search.html

To remove yourself from this list, go to http://www.jag-lovers.org/cgi-bin/majordomo.

You go, hoon!

Alex
79xj6L SII

BHornaday@aol.com wrote:

[clip]>

BTW, I decided that yellow was not appropriate for the fan blades so I have
decided to paint everything that spins, twirls, or otherwise moves bright
green and all the braking system parts red (green for go, red for stop…)

Sorry for rambling.

Bruce "Hoon"aday
1980 Ser III 4.2L
1959 Plymouth Fury
1991 Ford E-150 Custom Van

===================================================
The archives and FAQ will answer many queries on the XJ series…
FAQs: http://www.jag-lovers.org/xjlovers/xjfaq/xjfaq.html
Archives: http://www.jag-lovers.org/lists/search.html

To remove yourself from this list, go to http://www.jag-lovers.org/cgi-bin/majordomo.