Startup idle-too fast

T

tom geiger

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Dec 31, 2006
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So I’m heading over to pick up the motorhome and have in past experienced a pretty fast idle that does not want to drop off till I run it out on the
road for a bit. I’ve readjusted the electric choke back to a middle setting but that has not any difference on the fast idle. This is a quadrojet
Rodchester I believe. Where would be the fast idle adjustment screw on these? I’ve seen videos online that show them on the drivers side if
looking at it from the front. When I look at it I don’t see anything there as in the video.

Anyhow,
Thanks
TG
--
Tom Geiger
76 Eleganza II
KCMO
 
Tom, 0n the passenger side, near the choke, is a gravity controlled linkage
that is part of the fast idle circuit. It is frequently sticky, due in part
to the choke stove below it. Spray it with Kroll or something similaron a
cold engine, and manipulate the linkage by hand until it is free. See if
that helps.
Jim Hupy
Salem, Oregon

On Thu, Oct 22, 2020, 10:05 AM tom geiger via Gmclist <

> So I’m heading over to pick up the motorhome and have in past experienced
> a pretty fast idle that does not want to drop off till I run it out on the
> road for a bit. I’ve readjusted the electric choke back to a middle
> setting but that has not any difference on the fast idle. This is a
> quadrojet
> Rodchester I believe. Where would be the fast idle adjustment screw on
> these? I’ve seen videos online that show them on the drivers side if
> looking at it from the front. When I look at it I don’t see anything
> there as in the video.
>
> Anyhow,
> Thanks
> TG
> --
> Tom Geiger
> 76 Eleganza II
> KCMO
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
 
Where are you pulling the power to the elec
tric choke.

On Thu, Oct 22, 2020 at 10:20 AM James Hupy via Gmclist <

> Tom, 0n the passenger side, near the choke, is a gravity controlled linkage
> that is part of the fast idle circuit. It is frequently sticky, due in part
> to the choke stove below it. Spray it with Kroll or something similaron a
> cold engine, and manipulate the linkage by hand until it is free. See if
> that helps.
> Jim Hupy
> Salem, Oregon
>
> On Thu, Oct 22, 2020, 10:05 AM tom geiger via Gmclist <

>
> > So I’m heading over to pick up the motorhome and have in past experienced
> > a pretty fast idle that does not want to drop off till I run it out on
> the
> > road for a bit. I’ve readjusted the electric choke back to a middle
> > setting but that has not any difference on the fast idle. This is a
> > quadrojet
> > Rodchester I believe. Where would be the fast idle adjustment screw on
> > these? I’ve seen videos online that show them on the drivers side if
> > looking at it from the front. When I look at it I don’t see anything
> > there as in the video.
> >
> > Anyhow,
> > Thanks
> > TG
> > --
> > Tom Geiger
> > 76 Eleganza II
> > KCMO
> >
> > _______________________________________________
> > 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
>

--
Jim Kanomata
Applied/GMC, Newark,CA
jimk
http://www.gmcrvparts.com
1-800-752-7502
 
If choke set cold and it’s too fast, back off fast idle cam screw on pass side. It rides on stepped cam. A little goes a long way and what you
think is too fast may be correct.
--
John Lebetski
Woodstock, IL
77 Eleganza II
 
Tom,
If adjusting the choke does not help, then pull the cover off and see that
it is pushing or pulling on the lever and then set it,

On Thu, Oct 22, 2020 at 2:38 PM John R. Lebetski via Gmclist <

> If choke set cold and it’s too fast, back off fast idle cam screw on pass
> side. It rides on stepped cam. A little goes a long way and what you
> think is too fast may be correct.
> --
> John Lebetski
> Woodstock, IL
> 77 Eleganza II
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>

--
Jim Kanomata
Applied/GMC, Newark,CA
jimk
http://www.gmcrvparts.com
1-800-752-7502
 
Good question Jim K, had a mechanic install the electric choke for me so I don’t know where he pulled it from. I did take a read on it and it does
read 12v at the connection.

I will spray that linkage with WD and work it a bit. I’ll also adjust that screw to see if I can get the fast idle down a bit. 950rpm or so?
Right now the idle climbs up to at least 2k and possibly even higher so its certainly racing.

On the choke adjustment, what should it be adjusted to for winter starts as oppose to summer starts?

Thanks,
Tom
--
Tom Geiger
76 Eleganza II
KCMO
 
Tom,
1500rpm max

On Thu, Oct 22, 2020 at 6:00 PM tom geiger via Gmclist <

> Good question Jim K, had a mechanic install the electric choke for me so
> I don’t know where he pulled it from. I did take a read on it and it does
> read 12v at the connection.
>
> I will spray that linkage with WD and work it a bit. I’ll also adjust
> that screw to see if I can get the fast idle down a bit. 950rpm or so?
> Right now the idle climbs up to at least 2k and possibly even higher so
> its certainly racing.
>
> On the choke adjustment, what should it be adjusted to for winter starts
> as oppose to summer starts?
>
> Thanks,
> Tom
> --
> Tom Geiger
> 76 Eleganza II
> KCMO
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>

--
Jim Kanomata
Applied/GMC, Newark,CA
jimk
http://www.gmcrvparts.com
1-800-752-7502
 
Tom,

The choke pull off difference between 12.0V from the ignition and the 13.5 that is the alternator output is significant. I had mine to the alternator
first and it was a little too fast for Michigan. I wanted the alternator so it did not start timing until the engine was running and it came off too
fast for the rebuilt engine, so I added an inline diode to drop the choke signal that 0.7 volts and now it is even better than the choke stove set up.


KCMO to day will top out at about 50°F. If you set the choke so it is just closed at that temperature, it will be about right. All the engine has
to do is start and you are good. You may have to give it another half a minute before you can throttle up, but that is a good idea anyway.

Other note... WD40 is NOT a lubricant. It is and was formulated to be a drying agent. It will do some penetration, but that linkage really needs a
lubricant.

Matt
--
Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
 
Ok Matt, won’t use WD but rather “Free All”, its formulated to free up anything its sprayed onto. That should work.
I’m going to try to set the choke flap according to what was described because when I went over to pick it up and bring it back to the house it
started up pretty quickly, slowly worked its revs up to 2k plus and had to let it run for awhile, 5-8 minutes before it wouldn’t stall when I put in
drive. Really inconvenient when trying to start it up and get going after a weekend camping. Just acts a little cold after I did the crossover
blockoffs.

TG
--
Tom Geiger
76 Eleganza II
KCMO
 
> Ok Matt, won’t use WD but rather “Free All”, its formulated to free up anything its sprayed onto. That should work.
> I’m going to try to set the choke flap according to what was described because when I went over to pick it up and bring it back to the house it
> started up pretty quickly, slowly worked its revs up to 2k plus and had to let it run for awhile, 5-8 minutes before it wouldn’t stall when I put
> in drive. Really inconvenient when trying to start it up and get going after a weekend camping. Just acts a little cold after I did the crossover
> blockoffs.
>
> TG

TG,

The above says that the idle tuning is not right.
Unfortunately, I am not good enough to tell you where it most likely could use adjustment. There really are just two things, mixture and timing.
Mixture is the combination of the choke plate starting position, the throttle stop screw and the two idle jet screws that and under the float bowl.
Those are a bear to get to without the "around the corner" screw driver. The timing is not a bad bet if you eliminated the TVS from the system.

Matt
--
Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
 
I kinda hesitate to jump into this pond, but, what the heck! Here goes
nuttin'. Absolutely stone cold engine. Open Hatch. Remove Air cleaner.
Place kneeling board across hatch opening. GENTLY, touch the closed choke
plate. Oh, you say, the choke plate is not closed all the way. Reach over
and push ONCE on the accelerator. The choke linkage should set the choke
in the closed position. If that does not happen, spray the crap out of all
the carb linkage with a lubricating spray. NOT WD-40!. Kroil or similar
works fine. Make sure linkage is freed up.
Then, lightly take one finger and GENTLY touch the closed choke plate.
Just the slightest touch should move the choke plate. If not, find a small
right angle standard screwdriver, and loosen but do not remove the three
screws holding the black phenolic choke cover in place. Turn the choke
cover and watch the choke plate. It should move towards the open position.
Then, slowly, move the choke cover just enough to JUST CLOSE the choke
plate. Touch it lightly with your finger. It should move towards the open
position with just the slightest touch. Tighten those 3 screws. Re-install
the air cleaner. Get in the driver's seat, and start the engine. It should
start right up. If it starts and dies, remove the air cleaner and look at
the choke plate. It should still be closed. If it is open, the electric
heating coil is overheating the thermostatic spring in the choke. If that
is the case, find a power source that does not come on until the alternator
starts charging. That should help. If this basic adjustment is beyond your
skill level, take the coach to someone who can do the adjustment.
Jim Hupy
Salem, Oregon

On Sat, Oct 24, 2020, 7:54 AM Matt Colie via Gmclist <

> > Ok Matt, won’t use WD but rather “Free All”, its formulated to free up
> anything its sprayed onto. That should work.
> > I’m going to try to set the choke flap according to what was described
> because when I went over to pick it up and bring it back to the house it
> > started up pretty quickly, slowly worked its revs up to 2k plus and had
> to let it run for awhile, 5-8 minutes before it wouldn’t stall when I put
> > in drive. Really inconvenient when trying to start it up and get going
> after a weekend camping. Just acts a little cold after I did the crossover
> > blockoffs.
> >
> > TG
>
> TG,
>
> The above says that the idle tuning is not right.
> Unfortunately, I am not good enough to tell you where it most likely could
> use adjustment. There really are just two things, mixture and timing.
> Mixture is the combination of the choke plate starting position, the
> throttle stop screw and the two idle jet screws that and under the float
> bowl.
> Those are a bear to get to without the "around the corner" screw driver.
> The timing is not a bad bet if you eliminated the TVS from the system.
>
> Matt
> --
> Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL,
> GMCES
> Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum
> Brakes with Applied Control Arms
> SE Michigan - Near DTW - Twixt A2 and Detroit
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
 
Ok, I’ve gone back over the choke setting and flap is shut. I also sprayed all the linkage with “Free All”. If that stuff doesn’t get things
working I’m not sure what will. I’m letting that stuff work over night and will start it tomorrow morning. I have located the startup idle screw
and not sure how I’ll reach it with all the stuff in the way. Also is that screw a star screw, or possibly allen wrench? Tried a phillips on it
and it seemed to not be what it was.

Thanks,
TG
--
Tom Geiger
76 Eleganza II
KCMO
 
It is normally a slotted screw, unless a rebuilder has replaced it with a
"tamper resistant" version. Then, all bets are off.
Jim Hupy
Salem, Oregon

On Mon, Oct 26, 2020, 1:35 PM tom geiger via Gmclist <

> Ok, I’ve gone back over the choke setting and flap is shut. I also
> sprayed all the linkage with “Free All”. If that stuff doesn’t get things
> working I’m not sure what will. I’m letting that stuff work over night
> and will start it tomorrow morning. I have located the startup idle screw
> and not sure how I’ll reach it with all the stuff in the way. Also is
> that screw a star screw, or possibly allen wrench? Tried a phillips on it
> and it seemed to not be what it was.
>
> Thanks,
> TG
> --
> Tom Geiger
> 76 Eleganza II
> KCMO
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
 
> Ok, I’ve gone back over the choke setting and flap is shut. I also sprayed all the linkage with “Free All”. If that stuff doesn’t get
> things working I’m not sure what will. I’m letting that stuff work over night and will start it tomorrow morning. I have located the startup
> idle screw and not sure how I’ll reach it with all the stuff in the way. Also is that screw a star screw, or possibly allen wrench? Tried a
> phillips on it and it seemed to not be what it was.
>
> Thanks,
> TG

Tom,

This is why I carry the 9$ box from hazard fright that has almost all the points I have seen.

It is probably in there. Then all you need is a 1/4 socket.

Matt
--
Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
 
Hazard Fright, like it. Yes that place is my place to go, that and a local Home Improvement store called Menards. So I think I’ll have the star
driver I’ll need cuz after hitting it with degreaser I can see thats what it is. Wish me luck in the morning. I’ll report how it goes.

Thanks,
TG
--
Tom Geiger
76 Eleganza II
KCMO
 
Well I went thru the adjustments and tried to start it and it would not start, so I loosened the screws on the choke cover and adjusted it so the flap
was nearly closed again and then tried it and it started right up. It did gradually start climbing in revs as it warmed up and I adjusted the idle
back to roughly 1000 to 1200rpm. Seem to not stall now with a much shorter warmup, so it seems to have worked. I did go thru this a couple years
ago and did notice the idle adjustment screw seemed to be a little loose when I adjusted it so I wonder if it simply vibrates out of adjustment over
time. Any ideas to help this?

Thanks,
Tom
--
Tom Geiger
76 Eleganza II
KCMO
 
> Well I went thru the adjustments and tried to start it and it would not start, so I loosened the screws on the choke cover and adjusted it so the
> flap was nearly closed again and then tried it and it started right up. It did gradually start climbing in revs as it warmed up and I adjusted the
> idle back to roughly 1000 to 1200rpm. Seem to not stall now with a much shorter warmup, so it seems to have worked. I did go thru this a couple
> years ago and did notice the idle adjustment screw seemed to be a little loose when I adjusted it so I wonder if it simply vibrates out of
> adjustment over time. Any ideas to help this?
>
> Thanks,
> Tom

Tom,

That idle speed adjust should be too tight to turn with fingers, manageable with a screwdriver. If it is looser than that, there are a couple of
fixes. The easiest is a single drop of PINK Loctite. There are others that all work better but are of increasing risk.

Matt

--
Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
 
There should be a little spring on the screw to keep it from backing off.
https://tinyurl.com/yycnyb7h (trying out my new tinyurl extension) ;-)

bdub

-----Original Message-----
From: On Behalf Of tom geiger via Gmclist
Sent: Thursday, October 29, 2020 7:13 AM

I did go thru this a couple years
ago and did notice the idle adjustment screw seemed to be a little loose
when I adjusted it so I wonder if it simply vibrates out of adjustment over
time. Any ideas to help this?
 
> Well I went thru the adjustments and tried to start it and it would not start, so I loosened the screws on the choke cover and adjusted it so the
> flap was nearly closed again and then tried it and it started right up. It did gradually start climbing in revs as it warmed up and I adjusted the
> idle back to roughly 1000 to 1200rpm. Seem to not stall now with a much shorter warmup, so it seems to have worked. I did go thru this a couple
> years ago and did notice the idle adjustment screw seemed to be a little loose when I adjusted it so I wonder if it simply vibrates out of
> adjustment over time. Any ideas to help this?
>
> Thanks,
> Tom

> There should be a little spring on the screw to keep it from backing off.
> https://tinyurl.com/yycnyb7h (trying out my new tinyurl extension) ;)
>
> bdub

It does not pain me at all to admit that Billy is right about this. Mine is missing and I didn't even know it should be there, I just fixed it.
I like the spring idea better.

Matt

--
Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
 
All this talk about choke settings & nobody has mentioned the vacuum pull off. When I had my 76 El II I had the choke set after many small adjustments that it started & ran like it was fuel injected.

Sent from my iPad stormn

>

>> Well I went thru the adjustments and tried to start it and it would not start, so I loosened the screws on the choke cover and adjusted it so the
>> flap was nearly closed again and then tried it and it started right up. It did gradually start climbing in revs as it warmed up and I adjusted the
>> idle back to roughly 1000 to 1200rpm. Seem to not stall now with a much shorter warmup, so it seems to have worked. I did go thru this a couple
>> years ago and did notice the idle adjustment screw seemed to be a little loose when I adjusted it so I wonder if it simply vibrates out of
>> adjustment over time. Any ideas to help this?
>>
>> Thanks,
>> Tom
>

>> There should be a little spring on the screw to keep it from backing off.
>> https://tinyurl.com/yycnyb7h (trying out my new tinyurl extension) ;)
>>
>> bdub
>
> It does not pain me at all to admit that Billy is right about this. Mine is missing and I didn't even know it should be there, I just fixed it.
> I like the spring idea better.
>
> Matt
>
> --
> Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
> Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
> SE Michigan - Near DTW - Twixt A2 and Detroit
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
 
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