Electric choke on carb

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burt and faye curtis

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Jun 3, 2012
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Ok, so now I know it needs a ground wire, sigh. But I don't see a place on
the carb to attach one. Where should I be looking.

Fay
76 Glenbrook
Kneeland, CA
 
The choke should ground through the carb. The power wire goes to a key hot source not constant 12V.
--
77 Royale, Rear Dry Bath. 403, 3.55 Final Drive, Lenzi goodies, Patterson carb and dizzy.
Mid Michigan
 
So is possible to have connected the positive wire incorrectly so it is
getting 15 to 16 volts when running? Hot lead is connected to center post
of isolator. And if it working correctly, how long should it be fast
idling? With air cleaner off, how can I tell it is doing what it is
supposed to be doing?

Fay
76 Glenbrook

The choke should ground through the carb. The power wire goes to a key
hot source not constant 12V.
--
77 Royale, Rear Dry Bath. 403, 3.55 Final Drive, Lenzi goodies, Patterson
carb and dizzy.
Mid Michigan

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Hi Fay
It probably does NOT need a ground wire. Use a test light. Attach one lead to the carb and the other lead to the battery positive terminal. If it lights then it is finding a ground through the carb.
Our carbs are metal and the bolts holding the carb to the manifold should ground it to the engine.

Emery Stora

>
> Ok, so now I know it needs a ground wire, sigh. But I don't see a place on
> the carb to attach one. Where should I be looking.
>
> Fay
> 76 Glenbrook
> Kneeland, CA
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
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Ok. Now my friend that installed it is telling me that there should also be
12 volts going to the choke when ign is turned on, but engine not running.
However I am reading zero. Is he right and should I find a different place
to draw power other than the terminal on the isolator?

On Fri, Jul 6, 2018, 4:07 PM Emery Stora via Gmclist <

> Hi Fay
> It probably does NOT need a ground wire. Use a test light. Attach one
> lead to the carb and the other lead to the battery positive terminal. If
> it lights then it is finding a ground through the carb.
> Our carbs are metal and the bolts holding the carb to the manifold should
> ground it to the engine.
>
> Emery Stora
>
> > On Jul 6, 2018, at 11:46 AM, Burt and Faye curtis <

> >
> > Ok, so now I know it needs a ground wire, sigh. But I don't see a place
> on
> > the carb to attach one. Where should I be looking.
> >
> > Fay
> > 76 Glenbrook
> > Kneeland, CA
> > _______________________________________________
> > GMCnet mailing list
> > Unsubscribe or Change List Options:
> > http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
>
> _______________________________________________
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Faye,

Your friend may not understand the operation of the isolator. That IS
where you want the electric choke connected. If it's hooked to an IGN
source, it will be powered and will open even if the engine is not
running. As it's wired, to the center terminal of the isolator, it will be
powered, and open, ONLY when the engine is running, causing the alternator
to power that terminal.
​
You definitely want the choke to open only with the engine running.

Ken H.

​

On Fri, Jul 6, 2018 at 7:13 PM Burt and Faye curtis <

> Ok. Now my friend that installed it is telling me that there should also be
> 12 volts going to the choke when ign is turned on, but engine not running.
> However I am reading zero. Is he right and should I find a different place
> to draw power other than the terminal on the isolator?
>
> On Fri, Jul 6, 2018, 4:07 PM Emery Stora via Gmclist <

>
> > Hi Fay
> > It probably does NOT need a ground wire. Use a test light. Attach one
> > lead to the carb and the other lead to the battery positive terminal. If
> > it lights then it is finding a ground through the carb.
> > Our carbs are metal and the bolts holding the carb to the manifold should
> > ground it to the engine.
> >
> > Emery Stora
> >
> > > On Jul 6, 2018, at 11:46 AM, Burt and Faye curtis <

> > >
> > > Ok, so now I know it needs a ground wire, sigh. But I don't see a place
> > on
> > > the carb to attach one. Where should I be looking.
> > >
> > > Fay
> > > 76 Glenbrook
> > > Kneeland, CA
> > > _______________________________________________
> > > GMCnet mailing list
> > > Unsubscribe or Change List Options:
> > > http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
> >
> >
> > _______________________________________________
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> >
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Thanks Ken. That is what I thought.

Fay

> Faye,
>
> Your friend may not understand the operation of the isolator. That IS
> where you want the electric choke connected. If it's hooked to an IGN
> source, it will be powered and will open even if the engine is not
> running. As it's wired, to the center terminal of the isolator, it will be
> powered, and open, ONLY when the engine is running, causing the alternator
> to power that terminal.
> ​
> You definitely want the choke to open only with the engine running.
>
> Ken H.
>
> ​
>
>
>
>
>
>
> On Fri, Jul 6, 2018 at 7:13 PM Burt and Faye curtis <

>
> > Ok. Now my friend that installed it is telling me that there should also
> be
> > 12 volts going to the choke when ign is turned on, but engine not
> running.
> > However I am reading zero. Is he right and should I find a different
> place
> > to draw power other than the terminal on the isolator?
> >
> > On Fri, Jul 6, 2018, 4:07 PM Emery Stora via Gmclist <

> >
> > > Hi Fay
> > > It probably does NOT need a ground wire. Use a test light. Attach one
> > > lead to the carb and the other lead to the battery positive terminal.
> If
> > > it lights then it is finding a ground through the carb.
> > > Our carbs are metal and the bolts holding the carb to the manifold
> should
> > > ground it to the engine.
> > >
> > > Emery Stora
> > >
> > > > On Jul 6, 2018, at 11:46 AM, Burt and Faye curtis <

> > > >
> > > > Ok, so now I know it needs a ground wire, sigh. But I don't see a
> place
> > > on
> > > > the carb to attach one. Where should I be looking.
> > > >
> > > > Fay
> > > > 76 Glenbrook
> > > > Kneeland, CA
> > > > _______________________________________________
> > > > GMCnet mailing list
> > > > Unsubscribe or Change List Options:
> > > > http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
> > >
> > >
> > > _______________________________________________
> > > GMCnet mailing list
> > > Unsubscribe or Change List Options:
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> > >
> > _______________________________________________
> > GMCnet mailing list
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> >
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Well here goes. I am going to stir the pot a bit here.

1st, there are two types of electric chokes. One that has only one wire connection and another that has a 2 wire plug. If you have a 1 wire type
then the choke grounds through the carb. With this type you need to remove the fiber gasket between the choke heater and the carb. Also on this type
I once saw where the carb did not ground well and the ground was going through the gas pedal linkage and sparking there. If you are not getting good
heat at the choke heater consider adding a single ground wire with tooth washers between the base of the carb and a good clean ground bolt on the
engine somewhere.

2nd, on the 2 wire choke a good ground needs to be run to a clean bolt on the intake somewhere. 2 wire choke heaters do NOT get ground through the
carb.

I have a 2 wire choke on my coach.
--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
 
Ken,

Thanks for clarifying. I have a one wire choke that gets 15 16 volts when
engine is running. Due to the trouble having with carb going to contingency
plan a - borrowing a friend's GMC and then most likely pulling carb and
sending it off to Patterson to be unmessed up again. Worked fine until
friend played with it and installed the choke.

Fay

76 Glenbrook that won't get to go to Canada

> Well here goes. I am going to stir the pot a bit here.
>
> 1st, there are two types of electric chokes. One that has only one wire
> connection and another that has a 2 wire plug. If you have a 1 wire type
> then the choke grounds through the carb. With this type you need to
> remove the fiber gasket between the choke heater and the carb. Also on
> this type
> I once saw where the carb did not ground well and the ground was going
> through the gas pedal linkage and sparking there. If you are not getting
> good
> heat at the choke heater consider adding a single ground wire with tooth
> washers between the base of the carb and a good clean ground bolt on the
> engine somewhere.
>
> 2nd, on the 2 wire choke a good ground needs to be run to a clean bolt on
> the intake somewhere. 2 wire choke heaters do NOT get ground through the
> carb.
>
> I have a 2 wire choke on my coach.
> --
> Ken Burton - N9KB
> 76 Palm Beach
> Hebron, Indiana
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
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>
 
Faye, some of the electric chokes are made a little different on the inside. Sometimes they are installed incorrectly and the thermal spring that
operates the choke isn't on the lever correctly. Might be worth removing 3 screws and retainers to check.
--
C. Boyd
76 Crestmont
East Tennessee
 
> Thanks for clarifying. I have a one wire choke that gets 15 16 volts when
> engine is running.

Once you get your choke sorted out please check your system voltage again. Voltage at the battery with engine off should be 12.5 - 12.7 V. With
engine running the voltage should be 13 - 14.5 V. If it is up in the 16 V range you have a voltage regulator that is dying.
--
Chris Geils - Twin Cities / W Wa
1978 26' Kingsley w/ very few mods; Headers, PD9040, aux trans cooler, one repaint in stock colors, R134a, Al rad, Alcoas, 50k mi
 
Chris,
I will look into that - could be one of the problems.
Thanks,
Fay

On Sat, Jul 7, 2018, 8:58 AM Chris Geils via Gmclist <

> > Thanks for clarifying. I have a one wire choke that gets 15 16 volts when
> > engine is running.
>
> Once you get your choke sorted out please check your system voltage
> again. Voltage at the battery with engine off should be 12.5 - 12.7 V.
> With
> engine running the voltage should be 13 - 14.5 V. If it is up in the 16 V
> range you have a voltage regulator that is dying.
> --
> Chris Geils - Twin Cities / W Wa
> 1978 26' Kingsley w/ very few mods; Headers, PD9040, aux trans cooler,
> one repaint in stock colors, R134a, Al rad, Alcoas, 50k mi
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
 
Don't worry much about 15 volts, Fay. You've said the choke is fed from
the center terminal of the isolator, so you're measuring the alternator
output voltage, which should be about 0.7 VDC higher than the voltage seen
by the battery. If you're reading 15 volts, that's a battery voltage of
14.3, which is within the range of a properly charging,
just-used-for-cranking battery. Now if you're REALLY seeing 16 volts,
that's a little high, assuming your meter is accurate (not a very good
bet). If you're not needing to replenish battery water frequently, I
wouldn't worry about it.

Ken H.

> > > Thanks for clarifying. I have a one wire choke that gets 15 16 volts
> when
> > > engine is running.
>
>
 
Faye, if you want to take a stab at setting that choke, this is how you go
about it.
1. Absolutely cold engine. Do not turn on the ignition key. Do not touch
the throttle. Remove the air cleaner, and look at the choke plate. It
should be open.
2. Touch the throttle with your hand and pull it back a little bit. The
choke should snap closed. Touch the choke plate very lightly and try to
open it. If it resists, it is set too rich. It should open with the
lightest of finger pressure against it.
3. To adjust the choke, loosen the three screws on the choke housing. You
do not need to remove them. The housing should be free to rotate. Turn the
choke housing in the direction that opens the choke plate, then the
opposite way, watching the choke plate as you do this. As soon as the choke
plate reaches the closed position, tighten the 3 screws without moving the
housing.
4. Turn on the ignition, but do not try to start it. Watch the choke plate.
It should NOT start to open if the engine is not running. If it opens, the
choke heater is hooked up incorrectly. It should only start to open when
the engine is running. A convenient place to hook it up is the center post
of the isolator.
This should get you going. If not, call me. I can talk you through what
comes next.
Jim Hupy

On Sat, Jul 7, 2018, 11:53 AM Burt and Faye curtis <

> Chris,
> I will look into that - could be one of the problems.
> Thanks,
> Fay
>
> On Sat, Jul 7, 2018, 8:58 AM Chris Geils via Gmclist <

>

> > > Thanks for clarifying. I have a one wire choke that gets 15 16 volts
> when
> > > engine is running.
> >
> > Once you get your choke sorted out please check your system voltage
> > again. Voltage at the battery with engine off should be 12.5 - 12.7 V.
> > With
> > engine running the voltage should be 13 - 14.5 V. If it is up in the 16
> V
> > range you have a voltage regulator that is dying.
> > --
> > Chris Geils - Twin Cities / W Wa
> > 1978 26' Kingsley w/ very few mods; Headers, PD9040, aux trans cooler,
> > one repaint in stock colors, R134a, Al rad, Alcoas, 50k mi
> >
> > _______________________________________________
> > GMCnet mailing list
> > Unsubscribe or Change List Options:
> > http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
> >
> _______________________________________________
> GMCnet mailing list
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> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
 
Jim,

Thanks for the instructions. I am pretty sure my choke plate is closed
when cold and takes a bit of pressure to move it. Not at home and won't be
back for a bit, but will see if I can work through it when I get back.

Fay
76 Glenbrook

> Faye, if you want to take a stab at setting that choke, this is how you go
> about it.
> 1. Absolutely cold engine. Do not turn on the ignition key. Do not touch
> the throttle. Remove the air cleaner, and look at the choke plate. It
> should be open.
> 2. Touch the throttle with your hand and pull it back a little bit. The
> choke should snap closed. Touch the choke plate very lightly and try to
> open it. If it resists, it is set too rich. It should open with the
> lightest of finger pressure against it.
> 3. To adjust the choke, loosen the three screws on the choke housing. You
> do not need to remove them. The housing should be free to rotate. Turn the
> choke housing in the direction that opens the choke plate, then the
> opposite way, watching the choke plate as you do this. As soon as the choke
> plate reaches the closed position, tighten the 3 screws without moving the
> housing.
> 4. Turn on the ignition, but do not try to start it. Watch the choke plate.
> It should NOT start to open if the engine is not running. If it opens, the
> choke heater is hooked up incorrectly. It should only start to open when
> the engine is running. A convenient place to hook it up is the center post
> of the isolator.
> This should get you going. If not, call me. I can talk you through what
> comes next.
> Jim Hupy
>
> On Sat, Jul 7, 2018, 11:53 AM Burt and Faye curtis <

>
> > Chris,
> > I will look into that - could be one of the problems.
> > Thanks,
> > Fay
> >
> > On Sat, Jul 7, 2018, 8:58 AM Chris Geils via Gmclist <

> >

> > > > Thanks for clarifying. I have a one wire choke that gets 15 16 volts
> > when
> > > > engine is running.
> > >
> > > Once you get your choke sorted out please check your system voltage
> > > again. Voltage at the battery with engine off should be 12.5 - 12.7 V.
> > > With
> > > engine running the voltage should be 13 - 14.5 V. If it is up in the
> 16
> > V
> > > range you have a voltage regulator that is dying.
> > > --
> > > Chris Geils - Twin Cities / W Wa
> > > 1978 26' Kingsley w/ very few mods; Headers, PD9040, aux trans cooler,
> > > one repaint in stock colors, R134a, Al rad, Alcoas, 50k mi
> > >
> > > _______________________________________________
> > > GMCnet mailing list
> > > Unsubscribe or Change List Options:
> > > http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
> > >
> > _______________________________________________
> > GMCnet mailing list
> > Unsubscribe or Change List Options:
> > http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
> >
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Faye, A couple of things.

1. With a one wire choke the gasket between the choke housing on the carb and the round thing you are turning with the heater in it needs to be
removed. That is how the electric heater gets it's ground.
It is possible that you are reading +15 or 16 volts at the choke but your meter is not connected to the ground side of the heater. The negative meter
lead is somewhere else that has a good ground. So what you are seeing is erroneous.

2. I do not like the voltage that you are reading on the center terminal of the isolator. Please read the voltage on the top and the bottom
terminals of the isolator. Use the aluminum plate that the isolator is mounted on for the negative meter lead connection when reading these
voltages. I am not worrying about the high voltage going to the choke but I am worried the the voltage going to the rest of the coach. The top and
bottom terminals of the isolator may be too high. Please humor me and take a quick reading there with the engine is idling.

3. A thought on the choke adjustment. It is summer. If you can not get the choke working correctly, for now adjust it all the way open. It will be
a little hard to start cold and you will have to pump the gas pedal a bit to get it started. After it warms for 30 to 45 seconds you will be good to
go. You can fix it later.

Ken B.
--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
 
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