93 F-150 AC Clutch will not engage
Chuck Duchon
clutch on the compressor does not engage. I checked the fuse under the
dashboard and it is OK. I thought I might luck out and find that the system
was low on R134 (the previous owner had it converted from the old type
Freon).
Bought a can of 134, system took a little it, and the gauge on the recharge
kit measured in the "full" range at 35 psi.
Is it possible for me to diagnose/replace a bad compressor clutch or should
I just bite the bullet and take it to an AC shop?
Thanks
Big Al
"Chuck Duchon" <cdu...@yahoo.com> wrote in message
news:IwdRc.5231$cT6....@fe2.columbus.rr.com...
not a lot of pressure for R134, unless you in a very cold place. Like about
40 degrees.
Al
Chuck
clutch is ok.
Tyrone
following; Follow the wire(s) from the A/C clutch and see where it/they
go. This will lead you to a switch that is operated by system pressure.
The switch looks similar to an oil pressure sender. As the pressure
increases and decreases, the switch alternates between open and closed.
This system has replaced the old bulb and thermostat of years gone by
because of it's simplicity. Remove the electrical connector from this
switch to the clutch. Hook up your multi-meter and read voltage from
the exposed pin to ground. With the A/C on, it should cycle between 12V
an 0V every 20 seconds or so. If you only have a continuity tester,
remove both wires from the switch an connect across both terminals. The
switch should cycle between "open" and "closed" at the same rate
mentioned before. If it does not, the switch is probably bad. Just
grab the switch by hand and screw it out of the fitting. There is a
shraeder valve behind it like a tire valve. That valve will
automatically seal the system upon removal of the switch. A new switch
is going to set you back about $30. Let us know how you come out.
"Chuck" <cste...@pacifier.com> wrote in message
news:10hb1mc...@corp.supernews.com...
TranSurgeon
"Tyrone" <Tyr...@innercity.com> wrote in message
news:uwhRc.185552$OB3....@bgtnsc05-news.ops.worldnet.att.net...
> If Chuck's suggestion shows that the clutch is good, proceed to the
> following; Follow the wire(s) from the A/C clutch and see where it/they
> go. This will lead you to a switch that is operated by system pressure.
> The switch looks similar to an oil pressure sender. As the pressure
> increases and decreases, the switch alternates between open and closed.
> This system has replaced the old bulb and thermostat of years gone by
> because of it's simplicity. Remove the electrical connector from this
> switch to the clutch. Hook up your multi-meter and read voltage from
> the exposed pin to ground. With the A/C on, it should cycle between 12V
> an 0V every 20 seconds or so.
if you have disconnected it, you won't see any voltage
cycling.............................
Tyrone
"TranSurgeon" <nobul...@mchsi.dotcom> wrote in message
news:FYpRc.267244$Oq2.23234@attbi_s52...
>
> "Tyrone" <Tyr...@innercity.com> wrote in message
> news:uwhRc.185552$OB3....@bgtnsc05-news.ops.worldnet.att.net...
> > If Chuck's suggestion shows that the clutch is good, proceed to the
> > following; Follow the wire(s) from the A/C clutch and see where
it/they
> > go. This will lead you to a switch that is operated by system
pressure.
> > The switch looks similar to an oil pressure sender. As the pressure
> > increases and decreases, the switch alternates between open and
closed.
> > This system has replaced the old bulb and thermostat of years gone
by
> > because of it's simplicity. Remove the electrical connector from
this
> > switch to the clutch. Hook up your multi-meter and read voltage
from
> > the exposed pin to ground. With the A/C on, it should cycle between
12V
> > an 0V every 20 seconds or so.
>
> if you have disconnected it, you won't see any voltage
> cycling.............................
Try reading it again. "Remove the electrical connector from this switch
to the clutch. Hook up your multi-meter and read voltage from the
exposed pin to ground. With the A/C on, it should cycle between 12V and
0V every 20 seconds or so." Maybe I should have made it clearer that we
are talking about reading between the exposed pin on the switch to
ground.
TranSurgeon
OK, I'm gonna be charitable here and run thru two different scenarios
1) you remove the wire from the switch and probe the wire end
result will be no cyclying, because you have removed the switch from the
circuit
2) you remove the wire from the compressor and probe the wire end
result will be no cycling, because the compressor isn't running
Back to you, Tom Edison............
Chuck Duchon
"Chuck" <cste...@pacifier.com> wrote in message
news:10hb1mc...@corp.supernews.com...
Chuck Duchon
"Tyrone" <Tyr...@innercity.com> wrote in message
news:uwhRc.185552$OB3....@bgtnsc05-news.ops.worldnet.att.net...
Tyrone
"TranSurgeon" <nobul...@mchsi.dotcom> wrote in message
Now it is my turn to return your charity.
1.) I have no idea which wire end you are probing as you don't say. If
it is the wire that runs from the switch to the compressor, and the
switch is working, and you measure from the exposed terminal of the
switch to ground, you will certainly read the cycling voltage as
constant DC voltage is connected to the hot terminal of the switch.
I can see where I might have confused the issue by saying to remove the
connector from the switch to the clutch. I should have said, on the
wire that goes to the clutch, remove the connector at the switch.
2) I said nothing about removing the wire at the compressor. I
suggested he remove the wire going to the compressor at the switch.
However, If you would like to remove the wire at the compressor go ahead
and do so. If you probe the wire, with the other lead to ground, and
the switch is working, you will again read a cycling voltage. That
voltage has absolutely nothing to do with whether the compressor is even
installed in the vehicle.
Back to you Einstein.
Tyrone
> Is there a positive and negative side on the compressor?
The negative side of the compressor is ground. The positive wire will
attach to the terminal on the clutch. To do a test of the clutch, all
you need to do is momentarily jump a wire from the positive terminal of
your battery to the terminal on the clutch. If it is working you will
hear and see it engage. There is no need to have the engine running for
this test.
TranSurgeon
if you break the circuit ANYWHERE, the clutch will no longer be in
operation, and hence, no cycling can occur
>
> I can see where I might have confused the issue by saying to remove the
> connector from the switch to the clutch. I should have said, on the
> wire that goes to the clutch, remove the connector at the switch.
>
> 2) I said nothing about removing the wire at the compressor. I
> suggested he remove the wire going to the compressor at the switch.
> However, If you would like to remove the wire at the compressor go ahead
> and do so. If you probe the wire, with the other lead to ground, and
> the switch is working, you will again read a cycling voltage. That
> voltage has absolutely nothing to do with whether the compressor is even
> installed in the vehicle
to this point, I was willing to think perhaps I had mis-undestood your
directions, BUT................
so now you claim that the switch will cycle (which is caused by pressures
going up and down in the low side of the system), even without a compressor
???
I think perhaps you should read up (or better yet, take a look under the
hood) before you make a TOTAL ass of youorself
David M
to form:
>
> I think perhaps you should read up (or better yet, take a look under the
> hood) before you make a TOTAL ass of youorself
Too late, he already did.
--
David M (dmacchiarolo)
http://home.triad.rr.com/redsled
T/S 53
sled351 Linux 2.4.18-14 has been up 30 days 6:28
TranSurgeon
"David M" <NOS...@nospam.com> wrote in message
news:pan.2004.08.09.23.32.06.468209@sled351...
> On Mon, 09 Aug 2004 14:09:49 +0000, TranSurgeon rearranged some electrons
> to form:
>
>
> >
> > I think perhaps you should read up (or better yet, take a look under the
> > hood) before you make a TOTAL ass of youorself
>
> Too late, he already did.
>
yeah, I thought that 'cycling even with no compressor' was pretty much a
hoot
JS
<snip>
> Back to you Einstein.
>
>
Wouldn't it just be a whole lot easier to check for voltage at the
clutch. If available, the clutch is bad. If not available check for
voltage on the positive side of the pressure switch. If available, just
pull both wires at the pressure switch and check for continuity across
the switch. This is a normally closed switch.
Marsh Monster
.
=========
=========
Re: 93 F-150 AC Clutch will not engage
Group: alt.trucks.ford Date: Tue, Aug 10, 2004, 4:38pm (CDT+5) From:
J...@att.net (JS)
wrote in message
Wouldn't it just be a whole lot easier to check for voltage at the
clutch. If available, the clutch is bad.
If not available check for voltage on the positive side of the pressure
switch. If available, just pull both wires at the pressure switch and
check for continuity across the switch.
This is a normally closed switch.
============
============
MarshMonster
gives his 2 cents....
Unless there's no preasure.....
then it's normally open.
oo
L
O
Other than that.....your advice is sound,
and better yet, the easiest to understand
in the thread so far. Short,simple, and
easy to do.
lol @ Tyrone
respectfully,
~:~
MarshMonster
~suggests unhooking the connector at
the preasure switch first..and jumping across
the terminals with a paper clip to see if the
clutch even works~
========
Brian Orion
wire will attach to the terminal on the clutch. To do a test of the
clutch, all you need to do is momentarily jump a wire from the positive
terminal of your battery to the terminal on the clutch. If it is working
you will hear and see it engage. There is no need to have the engine
running for this test."
I hate to butt into this thread but how on earth can you check the
clutch operation without the motor running? Sure you might hear a
click,but you wont see the compressor turn will you?so how do you know
if it's smoked or not?Do it with the motor running and check that the
compressor engages!
Rex B
||Regarding " The negative side of the compressor is ground. The positive
||wire will attach to the terminal on the clutch. To do a test of the
||clutch, all you need to do is momentarily jump a wire from the positive
||terminal of your battery to the terminal on the clutch. If it is working
||you will hear and see it engage. There is no need to have the engine
||running for this test."
||==========$$$$$$$$$$$$============
||
|| I hate to butt into this thread but how on earth can you check the
||clutch operation without the motor running? Sure you might hear a
||click,but you wont see the compressor turn will you?
Sure you will. Clutch off, the pulleys run but the center does not.
Clutch on, the center starts revolving. If the center is turning, it's likely
the compressor is pumping.
Texas Parts Guy
Rex B
||On Sat, 07 Aug 2004 23:24:24 GMT, "Chuck Duchon"
||If you only have 35 psi in a dead system which it is if the
||clutch won't engage, you are probably low. That said, the
||clutch cycling switch should be closed around 40 psi or
||higher. At 35 psi, you probably don't have enough static
||system pressure to close the cc switch. You are probably in
||need of more refrigerant.
So you short across the switch contacts to make the cltuch hook up and it will
take more refrigerant.
Texas Parts Guy
TranSurgeon
"Rex B" <rex@@txol.net> wrote in message
news:411a65a4....@news.txol.net...
without the engine running ???
Good Grief