starting the engine

if you move the throttle by hand at the carb ( where the throttle cable attaches ) the choke butterfly should close.

there are a bunch of linkages involved that may or may not be working as expected.

On the passenger side of the carb is the choke spring that is supposed to move the butterfly ( flapper ), but there can be a dozen reasons it doesn't.

The simplest is it's mis adjusted. There are 3 screws on the face that hold a black plastic piece in place. Rotating that adjusts the choke.

With the engine cold you rotate it till it just closes, then snug up the screws.

If your choke system is working it will open as the engine warms up.

Note that the choke will NOT open until you blip the throttle as the mechanism keeps it in place. If you grew up in the north with carberated cars you will remember them racing untill they warmed up and you kicked the throttle.

The gas filter is screwed into the front of the carb, theres a metal tube that snakes around the radiator hose and connects to the carb. The filter is inside there.

It's usually on too tight and it will leak gas when you open it. so have some paper towels ready. Use 2 wrenches, 1 to hold the filter and the second to loosen the gas line, then loosen the filter.

You have to bend the gas line a little to get it all apart.

The filter has a right and wrong way to go in, I always forget which is right, so check the archives!

________________________________
From: Gmclist on behalf of kelly stockwell
Sent: Monday, August 14, 2017 2:45:28 PM
To: gmclist
Subject: Re: [GMCnet] starting the engine

Ok, so i'm right about what the choke is, and that the green thing is in a vacuum line

Now, how is the pedal going to the floor (once) supposed to close the choke? I can move things but I don't know what should move together, what
should move the lever that moves the choke flapper?

I'm not having luck looking at images online for what moves what plates.

And finally, there's supposed to be a tiny gas filter in the carb, looks like a small gold microphone.

how do i get to/change that?

thanks
kelly
--
1978 Kingsley
Putney VT

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Fuel filter change video. Easier to watch than type. Use line wrenches. so you dont strip the fuel line. ALWAYS put a second wrench on the filter
housing so you dont damage that attempting to loosen the fuel line.

https://www.youtube.com/watch?v=WK0sqMI6mMs

When you push the gas pedal to the floor the choke plate should snap closed. You will see the plate close up and probably hear it. This is on a
stone cold engine... If on a cold engine that choke plate is not nearly all the way closed up, it may need some adjustment. I recall that coach came
from Meeshigun. Climate being somewhat similar I would be surprised if it wasn't correctly set up.
--
77 Royale, Rear Dry Bath. 403, 3.55 Final Drive, Lenzi goodies, Patterson carb and dizzy.
Mid Michigan
 
Pushing the accelerator pedal to the floor SLOWLY when the engine is cold, frees up the choke activation spring to allow the butterfly to close.

D C "Mac" Macdonald
Amateur Radio K2GKK
Since 30 November '53
USAF and FAA, Retired
Member GMCMI & Classics
Oklahoma City, OK
"The Money Pit"
TZE166V101966
'76 ex-Palm Beach
k2gkk + hotmail dot com

________________________________
From: Gmclist on behalf of kelly stockwell
Sent: Monday, August 14, 2017 14:45
To: gmclist
Subject: Re: [GMCnet] starting the engine

Ok, so i'm right about what the choke is, and that the green thing is in a vacuum line

Now, how is the pedal going to the floor (once) supposed to close the choke? I can move things but I don't know what should move together, what
should move the lever that moves the choke flapper?

I'm not having luck looking at images online for what moves what plates.

And finally, there's supposed to be a tiny gas filter in the carb, looks like a small gold microphone.

how do i get to/change that?

thanks
kelly
--
1978 Kingsley
Putney VT

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Gmclist Info Page - GMCnethttp://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
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Keith
Nothing on top of the carb (butterfly) closed. it stayed partly open. By the throttle you mean on the driver's side the chain. That's what moved
when I stepped on the pedal. A flapper below the choke did move with the throttle. It could be so out of wack it doesnt move?

On the passenger side, it seemed like nothing connected the flapper of the choke to any of the parts I could move with my hand. I can move the choke
on the passenger side and moving the choke itself.

I'm not sure I'm fully explaining it right.

It did start right up 1/2 hour after I first started it; so it runs fine and I believe the choke is not closing, it's staying partly open.

I'll look for that fuel filter, I wasn't sure if it was in the carburetor or outside it. Sounds like it's outside it and I should follow the metal
fuel lines.

thanks for the continued help! I had an RX-7 with a manual choke I pulled out, it would pop back in once it was warmed up. Manual meant I determined
when to use it.
kelly

butterfly should close.

there are a bunch of linkages involved that may or may not be working as expected.

On the passenger side of the carb is the choke spring that is supposed to move the butterfly ( flapper ), but there can be a dozen reasons it
doesn't.

The simplest is it's mis adjusted. There are 3 screws on the face that hold a black plastic piece in place. Rotating that adjusts the choke.

With the engine cold you rotate it till it just closes, then snug up the screws.

If your choke system is working it will open as the engine warms up.

Note that the choke will NOT open until you blip the throttle as the mechanism keeps it in place. If you grew up in the north with carberated cars you
will remember them racing untill they warmed up and you kicked the throttle.

The gas filter is screwed into the front of the carb, theres a metal tube that snakes around the radiator hose and connects to the carb. The filter is
inside there.

It's usually on too tight and it will leak gas when you open it. so have some paper towels ready. Use 2 wrenches, 1 to hold the filter and the second
to loosen the gas line, then loosen the filter.

You have to bend the gas line a little to get it all apart.

The filter has a right and wrong way to go in, I always forget which is right, so check the archives!

________________________________
From: Gmclist on behalf of kelly stockwell
Sent: Monday, August 14, 2017 2:45:28 PM
To: mailto:gmclist
Subject: Re: [GMCnet] starting the engine

Ok, so i'm right about what the choke is, and that the green thing is in a vacuum line

Now, how is the pedal going to the floor (once) supposed to close the choke? I can move things but I don't know what should move together, what
should move the lever that moves the choke flapper?

I'm not having luck looking at images online for what moves what plates.

And finally, there's supposed to be a tiny gas filter in the carb, looks like a small gold microphone.

how do i get to/change that?

thanks
kelly
--
1978 Kingsley
Putney VT

_______________________________________________
--
1978 Kingsley
Putney VT
 
Mac
I saw nothing move when I first pushed the pedal down.

> Pushing the accelerator pedal to the floor SLOWLY when the engine is cold, frees up the choke activation spring to allow the butterfly to close.
>
>
> D C "Mac" Macdonald
> Amateur Radio K2GKK
> Since 30 November '53
> USAF and FAA, Retired
> Member GMCMI & Classics
> Oklahoma City, OK
> "The Money Pit"
> TZE166V101966
> '76 ex-Palm Beach
> k2gkk + hotmail dot com
>
>
> ________________________________
> From: Gmclist on behalf of kelly stockwell
> Sent: Monday, August 14, 2017 14:45
> To: gmclist
> Subject: Re: [GMCnet] starting the engine
>
> Ok, so i'm right about what the choke is, and that the green thing is in a vacuum line
>
> Now, how is the pedal going to the floor (once) supposed to close the choke? I can move things but I don't know what should move together, what
> should move the lever that moves the choke flapper?
>
> I'm not having luck looking at images online for what moves what plates.
>
> And finally, there's supposed to be a tiny gas filter in the carb, looks like a small gold microphone.
>
> how do i get to/change that?
>
> thanks
> kelly
> --
> 1978 Kingsley
> Putney VT
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
> Gmclist Info Page - GMCnet
> list.gmcnet.org
> To see the collection of prior postings to the list, visit the Gmclist Archives. Using Gmclist: To post a message to all the list members, send
> email ...
>
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org

--
1978 Kingsley
Putney VT
 
thank you for the video link! Nothing snaps closed. What I need to figure out is what should be connected to what to make it snap closed. It
doesn't move at all; like the link is gone

> Fuel filter change video. Easier to watch than type. Use line wrenches. so you dont strip the fuel line. ALWAYS put a second wrench on the
> filter housing so you dont damage that attempting to loosen the fuel line.
>
> https://www.youtube.com/watch?v=WK0sqMI6mMs
>
>
>
>
> When you push the gas pedal to the floor the choke plate should snap closed. You will see the plate close up and probably hear it. This is on a
> stone cold engine... If on a cold engine that choke plate is not nearly all the way closed up, it may need some adjustment. I recall that coach
> came from Meeshigun. Climate being somewhat similar I would be surprised if it wasn't correctly set up.

--
1978 Kingsley
Putney VT
 
I just know how it is supposed to work! Know nothing about how to fix it!

HAR!

Mac in OKC

________________________________
From: Gmclist on behalf of kelly stockwell
Sent: Monday, August 14, 2017 18:02
To: gmclist
Subject: Re: [GMCnet] starting the engine

Mac
I saw nothing move when I first pushed the pedal down.

> Pushing the accelerator pedal to the floor SLOWLY when the engine is cold, frees up the choke activation spring to allow the butterfly to close.
>
>
> D C "Mac" Macdonald
> Amateur Radio K2GKK
> Since 30 November '53
> USAF and FAA, Retired
> Member GMCMI & Classics
> Oklahoma City, OK
> "The Money Pit"
> TZE166V101966
> '76 ex-Palm Beach
> k2gkk + hotmail dot com
 
I think we're beyond what we can do remotely with pictures.

My guess / bet is that the choke is out of adjustment, maybe because the heater is rusted through...

You need to find someone local that can lay hands on it or send it to Dick Patterson, Or Jim B?

________________________________
From: Gmclist on behalf of D C _Mac_ Macdonald
Sent: Monday, August 14, 2017 8:35:36 PM
To: gmclist
Subject: Re: [GMCnet] starting the engine

I just know how it is supposed to work! Know nothing about how to fix it!

HAR!

Mac in OKC

________________________________
From: Gmclist on behalf of kelly stockwell
Sent: Monday, August 14, 2017 18:02
To: gmclist
Subject: Re: [GMCnet] starting the engine

Mac
I saw nothing move when I first pushed the pedal down.

> Pushing the accelerator pedal to the floor SLOWLY when the engine is cold, frees up the choke activation spring to allow the butterfly to close.
>
>
> D C "Mac" Macdonald
> Amateur Radio K2GKK
> Since 30 November '53
> USAF and FAA, Retired
> Member GMCMI & Classics
> Oklahoma City, OK
> "The Money Pit"
> TZE166V101966
> '76 ex-Palm Beach
> k2gkk + hotmail dot com

_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
 
1)From your picture the fresh air line to the choke stove looks kinked up top where it draws clean air from back of carb.
2) the hot side of the line coming from the manifold to the carb looks rusted. This means that the loop down in the manifold is probably rotted away.

3) this means the choke thermostat will not get proper heat signal causing the choke to not open properly
4) so-- because of this someone has probably loosened the 3 screws on the choke thermostat and de-adjusted the thermostat to the Lean side to
circumvent the choke staying on.
The choke heat lines will need replacing, choke spring and housing cleaned, then re-adjusted
My arm chair diagnostics from the picture
--
John Lebetski
Woodstock, IL
77 Eleganza II
 
Here's some parts:
http://appliedgmc.com/search.itml?icQuery=choke

Actually, a modern electric choke would be nice and close off that choke
stove. Jim can supply those as well.

And, close off the carb warping, manifold cracking exhaust crossover
ports. haha One good upgrade deserves another.....

How far are you from New England RV / Mike Glover in Plaistow, NH?

bdub

> 1)From your picture the fresh air line to the choke stove looks kinked up
> top where it draws clean air from back of carb.
> 2) the hot side of the line coming from the manifold to the carb looks
> rusted. This means that the loop down in the manifold is probably rotted
> away.
>
> 3) this means the choke thermostat will not get proper heat signal causing
> the choke to not open properly
> 4) so-- because of this someone has probably loosened the 3 screws on the
> choke thermostat and de-adjusted the thermostat to the Lean side to
> circumvent the choke staying on.
> The choke heat lines will need replacing, choke spring and housing
> cleaned, then re-adjusted
> My arm chair diagnostics from the picture
>
 
Pressing the throttle on a cold non-running engine should result in the front (choke) plate closing. If it does not, investigate whay. With the
three screws loose on the black round spring cover on the passenger side of the carb, rotating the black part with the throttle pressed and engine off
should move the choke plate in either direction. If it dies, turn it until the plate >just< closes and tighten the three screws. This will be close
to the correct setting. UIf the choke doesn't close, or binds, stop and figure put why and correct. Then set it again and try cranking the engine.
This assumes a stock setup with a 'stove pipe' running ffrom the stove on the manifold to the choke spring assembly. If you have a wire instead of a
heat tube, the setup will be a bit different.

--johnny

--johnny
--
76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
"I forgive them all, save those who hurt the dogs. They must answer to me in hell" - ol Andy, paraphrased
 
Again, thank you all. I realize it's hard to help diagnose with a photo or two. I have a friend who works on his cars willing to come take a look
this weekend. The comments on the vac lines are interesting; I'll take a look at that and see if anything is rotted. The fact is it drives fine, and
starts quickly when warmed up. So I'm hopeful it's just the choke out of wack. Last year when I posted here (or read here) about setting the choke
with the pedal to the floor it began starting right away when cold. So it was working not too long ago.

I'm 2+ hours from Plaistow NH (through what I imagine is some crappy traffic- being from VT crappy traffic is probably not what anyone else would call
it :). I know Mike is there and am grateful to have him nearby. So far I haven't talked to him or needed him.

What I really don't understand is how the choke plate should be connected to the bimetal spring contraption on the passenger side. The workings of
the plate and the movement of the levers don't touch each other, but I don't know how they're supposed to.

Hopefully this weekend my friend and I can diagnose. For now I'm certainly not dead in the water. With the choke not working, what's the best way to
cold start it? Stab the pedal down once or twice while cranking, and only crank for 10 seconds at a time?

-kelly

> Here's some parts:
> http://appliedgmc.com/search.itml?icQuery=choke
>
> Actually, a modern electric choke would be nice and close off that choke
> stove. Jim can supply those as well.
>
> And, close off the carb warping, manifold cracking exhaust crossover
> ports. haha One good upgrade deserves another.....
>
> How far are you from New England RV / Mike Glover in Plaistow, NH?
>
> bdub
>
>

>
> > 1)From your picture the fresh air line to the choke stove looks kinked up
> > top where it draws clean air from back of carb.
> > 2) the hot side of the line coming from the manifold to the carb looks
> > rusted. This means that the loop down in the manifold is probably rotted
> > away.
> >
> > 3) this means the choke thermostat will not get proper heat signal causing
> > the choke to not open properly
> > 4) so-- because of this someone has probably loosened the 3 screws on the
> > choke thermostat and de-adjusted the thermostat to the Lean side to
> > circumvent the choke staying on.
> > The choke heat lines will need replacing, choke spring and housing
> > cleaned, then re-adjusted
> > My arm chair diagnostics from the picture
> >
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org

--
1978 Kingsley
Putney VT
 
The standard choke uses a thermostatic coil that winds up the choke shaft
when it is cold, and unwinds it when it is warm. It is heated using a choke
stove, which is a loop of tubing that projects down into the exhaust
crossover in the intake manifold. A tube is connected to it and to the side
of the choke thermostat housing, which is the bell-shaped projection out
the starboard side of the carburetor.

The choke stove can rot out, sending exhaust gas directly to the carb
thermostat.

An electric choke works one of two ways, but both ways replace the choke
stove in the intake manifold. The method I prefer uses a temperature sensor
that is clamped under an intake manifold bolt, and an actuator that mounts
in the thermostat housing to replace the coil. It pulls the choke off as
the engine warms up. Both methods need power from the ignition circuit to
pull off the choke as the engine warms.

Rick "who has been down this road" Denney

> How does the electric choke work differently?
>
> kelly
> --
> 1978 Kingsley
> Putney VT
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
--
Rick Denney
73 x-Glacier 230 "Jaws"
Off-list email to rick at rickdenney dot com
 
Kelly,

The 455 & 403 engines in our GMC's use a thermostatic choke so Google "Thermostatic choke" and you'll find heaps of info on how they
work.

Then Google "Electric choke" and you'll find out how they work.

Regards,
Rob M.
The Pedantic Mechanic
Sydney, Australia
AUS '75 Avion - The Blue Streak TZE365V100428
USA '75 Avion - Double Trouble TZE365V100426
USA '77 Kingsley - TZE 267V100808

-----Original Message-----
From: Gmclist [mailto:gmclist-bounces] On Behalf Of kelly stockwell
Sent: Wednesday, August 16, 2017 9:19 PM
To: gmclist
Subject: Re: [GMCnet] starting the engine

How does the electric choke work differently?

kelly
--
1978 Kingsley
Putney VT
 
The choke plate has a small metal tab that protrudes through the passenger side of the carb. This tab fits loosely into a slot of the of end of the
metal choke spring which is covered by a plastic cover. As the metal in the spring expands and collapses due to the hot and cold of the engine the
spring will "tighten/wind up" with cold, and will loosen/unwind when it gets hot. The winding up or down of the spring is what moves the choke plate
open or closed on the actual carb.

So with a cold engine, the spring is wound up and it forces the choke plate in the closed position. As heat is applied to the choke spring either
through a choke stove/chimney tube with engine heat (which you have currently)or through an electrical connection (electric Choke)the choke plate will
gradually open up. This takes a few minutes to do as the engine warms.

An electric choke is essentially the same as far as parts, but there is one wire which needs to go to 12V when the key is on. (Key on Hot) With an
electric choke it does not matter if the engine is actually running, As long as the key is on the choke will warm up via electricity and will
gradually open up. They are adjusted in the same manner as a non electric choke.

Why someone wants an electric choke? Perhaps the choke stove pipes are bad (mine were) You can cap off / block off the choke plate on the intake
manifold and then run a single wire to key hot 12V and install the electric choke. It takes all of 10 minutes to install it.

They both work on the same principles.

That said. A hot engine when shut down will have the choke in the fully open position as it locks. To unlock the choke and get the butterfly plate
to close one must push the gas pedal to the floor, This squirts a bit of gas in the carb, and also snaps shut the choke butterfly plate.

You loosen, not remove, the three slotted screws with small hold down plates on the choke housing and rotate the assembly toward the rear of the coach
to adjust the choke to close more fully. Rotating it toward the front of the coach will open the choke more. This has to be done on a cold
engine so the spring is fully wound up.. By adjusting we are talking rotating the housing a few degrees, or millimeters to get the butterfly plate
fully closed, or very near fully closed. again on a cold engine.

Hope this helps.

--
77 Royale, Rear Dry Bath. 403, 3.55 Final Drive, Lenzi goodies, Patterson carb and dizzy.
Mid Michigan
 
Thanks all!

now i understand "stove" from the link of parts Bill added.

Ok, i'll do some reading and check it out again, maybe adding photos of what's going on at the passenger side. I don't think I want to change to an
electric choke, this one did work- thank you for the explanation.

cheers
kelly
--
1978 Kingsley
Putney VT
 
apologies if my questions are tiring

I think the comment about the stove being rusted out; and therefore my adjustment is way off sounds likely

I took some more pictures. How much do I need to remove to get to the stove?
I assume the U shaped stove item at Applied GMC is under the stove tube to choke. The pipe above looks rusty but feels solid.
Is this something I can do myself or should I enlist professional help? My next trip is August 28th, around a 4 hour drive to Maine. My only issue
now is cold starting.

I'm still confused about how the choke plate should be moved by the other moving parts..
I took this video of me moving parts
https://youtu.be/mIWiPhpi1BQ

--
1978 Kingsley
Putney VT
 
After watching, I wonder if the spring is properly connected. (I also wonder if that's the correct carb - have you checked the number stamped/cast on
the driver's side of the carb against the manual?)
Remove the three screws on the round black thing and pull it out - it is the temp spring which moved the choke plate. You should see in its housing a
metal tab which is connected directly to the choke plate: Moving the tab should move the plate without any slack or hesitation. There should be a
slot in the tab which ebngages the end of the spring to move the choke. If this is broken or not properly engaged, the choke will not work properly.
When it is properly engaged, rotating the spring holder should also move the choke in either direction. When it does, turn it until thye choke just
closes and then replace and tighten the three screws. You choke stove looks properl;y installed and should work. Your unloader diaphragm also
looks properly hooked.

--johnny
--
76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
"I forgive them all, save those who hurt the dogs. They must answer to me in hell" - ol Andy, paraphrased
 
Thank you Johnny, it also initially seemed to me like something was supposed to be connected but wasn't. Interesting comment on the right carb. I'll
try to look that up. the three screws on the round black thing are on the passenger side where the bimetal spring is (that's the spring people are
talking about not the visible spring?)

Just making sure i have the right parts in mind

kelly

> After watching, I wonder if the spring is properly connected. (I also wonder if that's the correct carb - have you checked the number
> stamped/cast on the driver's side of the carb against the manual?)
> Remove the three screws on the round black thing and pull it out - it is the temp spring which moved the choke plate. You should see in its
> housing a metal tab which is connected directly to the choke plate: Moving the tab should move the plate without any slack or hesitation. There
> should be a slot in the tab which ebngages the end of the spring to move the choke. If this is broken or not properly engaged, the choke will not
> work properly. When it is properly engaged, rotating the spring holder should also move the choke in either direction. When it does, turn it until
> thye choke just closes and then replace and tighten the three screws. You choke stove looks properl;y installed and should work. Your unloader
> diaphragm also looks properly hooked.
>
> --johnny

--
1978 Kingsley
Putney VT
 
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