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Home » Public Forums » GMCnet » electric choke hooked up (still stalling out)
electric choke hooked up [message #283177] Sun, 26 July 2015 07:02 Go to next message
budworks521 is currently offline  budworks521   United States
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Registered: October 2013
Location: Grand Rapids MI 1974 Pain...
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Well I had the well plugs resealed on the carb and also had the electric choke installed and I am still experience an engine that sounds great when running but eventually stalls out. I put a new temperature gauge in that doesn't use the electric feed and my tester said it had 12 volts going thru it. So I hooked up the choke to that and it doesn't open a full 90 degrees. So my question is does anyone know what the 74 455 engine temperature gauge line voltage is? And does it take a full 12 volts for the choke to fully open. Say it has 9 volts going thru it will it only open up 75%??? Otherwsise, I have the same symptoms, coach starts, runs fine and eventually stalls. I can restart the engine after stalling (3-5 minutes) and it will run for a bit. I am beginning to wonder if I have a leaky exhaust valve that causes back pressure in the manifold or some type of restricted exhaust (have replaced two mufflers as well). I am getting nowhere quick. I wish I had more tools to check stuff. If there is anyone near Lowell MI or Grand Rapids MI that could assist in the problems I would gladly pay for the help.

1974 Painted Desert 455 upper half rebuild constant project inexperienced mechanic Grand Rapids Mi Always trying to learn
Re: electric choke hooked up [message #283181 is a reply to message #283177] Sun, 26 July 2015 08:38 Go to previous messageGo to next message
kerry pinkerton is currently offline  kerry pinkerton   United States
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The choke works by heating the little coil spring which opens the choke as it expands. It is adjustable. Normally, you'd loosen the three flathead screws around the plastic cup and turn it until fully open when up to operating temp.

Do you have a vacuum gauge?


Kerry Pinkerton - North Alabama Had 5 over the years. Currently have a '06 Fleetwood Discovery 39L
Re: electric choke hooked up [message #283182 is a reply to message #283177] Sun, 26 July 2015 08:42 Go to previous messageGo to next message
JohnL455 is currently offline  JohnL455   United States
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I'm really confused by your post. Choke should have full switched 12V supply to the heating element.

John Lebetski
Woodstock, IL
77 Eleganza II
Re: electric choke hooked up [message #283185 is a reply to message #283177] Sun, 26 July 2015 08:53 Go to previous messageGo to next message
Dan is currently offline  Dan   United States
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Registered: August 2014
Location: Allentown, NJ
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Back when I was first getting the coach running I was having a similar problem. I also spent a lot of time messing with the choke. While it could be any number of things for me it was a fuel delivery problem. I was getting enough gas to fill up the bowl and run for a little while, then I'd run out of gas. Sounds ridiculously simple now, but at the time there was about a week where I would have sworn it was a choke/carb problem.

Dan DeLuca 1978 Eleganza II (http://imgur.com/gallery/YFHhK) Parked at Evil Monkey Farm in Allentown, New Jersey
Re: electric choke hooked up [message #283194 is a reply to message #283177] Sun, 26 July 2015 10:12 Go to previous messageGo to next message
budworks521 is currently offline  budworks521   United States
Messages: 137
Registered: October 2013
Location: Grand Rapids MI 1974 Pain...
Karma: 4
Senior Member
I am not sure on the fuel delivery pressure as I don't have an old school fuel pressure gauge. I have a vaccuum gauge and it is steady at 17 lbs or so with a very slight waver. So from what I understand is that the choke should have a full 12 volts to run properly. I guess I need to recheck the reading.

1974 Painted Desert 455 upper half rebuild constant project inexperienced mechanic Grand Rapids Mi Always trying to learn
Re: electric choke hooked up [message #283202 is a reply to message #283177] Sun, 26 July 2015 13:01 Go to previous messageGo to next message
kerry pinkerton is currently offline  kerry pinkerton   United States
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Registered: July 2012
Location: Harvest, Al
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Bud, right after it dies. Look down the front two barrels of the carb and pull the throttle linkage quickly back. You SHOULD see a jet of gas squirt out on each side. If not, there is no gas in the bowl and you have a fuel delivery problem....bad pump, clogged filter, etc. If there is a jet of fuel, it's not a fuel delivery problem.

Kerry Pinkerton - North Alabama Had 5 over the years. Currently have a '06 Fleetwood Discovery 39L
Re: electric choke hooked up [message #283222 is a reply to message #283177] Sun, 26 July 2015 18:39 Go to previous messageGo to next message
budworks521 is currently offline  budworks521   United States
Messages: 137
Registered: October 2013
Location: Grand Rapids MI 1974 Pain...
Karma: 4
Senior Member
I'll try the gas squirt thing but since it restarts again after waiting a few minutes it makes me think it is not a delivery issue. Sad part is the engine sounds awesome when running...

1974 Painted Desert 455 upper half rebuild constant project inexperienced mechanic Grand Rapids Mi Always trying to learn
Re: electric choke hooked up [message #283244 is a reply to message #283194] Sun, 26 July 2015 22:43 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
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Location: Hebron, Indiana
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There are two types of electric choke heaters out there. One is simply a heater that runs on 12 volts and has a single connector terminal. The other one has a two terminal connector and the ground side goes to a heat sensing thermistor. This type varies the voltage as the engine warms up and more closely tracks the actual engine temperature.

On the single terminal type the choke heater relies on the carb and choke mount to provide the ground side electrical connection. If this is what you have, the fiber gasket behind the choke needs to be removed to provide an adequate ground path. Also I have seen where the carb base does not get a good ground connection to the intake manifold through it's mounting. I would suggest if you are reading less than battery voltage at the choke that you you look closely at the ground side of the choke body to the intake manifold circuit. I have also seen where the carb was getting it's ground through the accelerator linkage as an alternate path to the normal mount to the intake manifold. You do not want this situation.


Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: [GMCnet] electric choke hooked up [message #283247 is a reply to message #283222] Sun, 26 July 2015 23:18 Go to previous message
Brian Waddell is currently offline  Brian Waddell   United States
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did you change the modulator if hei...brian 77 ele 455


> Date: Sun, 26 Jul 2015 17:39:31 -0600
> To: gmclist@list.gmcnet.org
> From: westmiman@comcast.net
> Subject: Re: [GMCnet] electric choke hooked up
>
> I'll try the gas squirt thing but since it restarts again after waiting a few minutes it makes me think it is not a delivery issue. Sad part is the
> engine sounds awesome when running...
> --
> 1974 Painted Desert
> 455 upper half rebuild
> constant project inexperienced mechanic
> Grand Rapids Mi
> Always trying to learn
>
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