2150 choke ?

[christopher]

on the choke housing there is one inlet for a heat tube, then pointing directly down is a large hole, when the engine is started I feel vacuum from it. now if the heat tube is to heat up the choke spring why would this hole drag in cold air? the choke heats up much faster if I occlude the hole. is something missing from there? I checked every source I have and can't find a reference to it. see my 87 GW has a hard time on cold starts. the choke closes and opens when warm but after start up she will bog and chug, then stall. when she stalls she spits gas out the top of the carb, when cold she also stalls when you press the gas. seems like it floods out. please adress the open hole in the choke

[okidoc]

Underneath the choke plate there is a plate on the intake mainfold that should have two holes in it. On my set up the rear hole has a hard line that attaches to a rear port on the spring housing. If my memory serves me right, the other attaches somewhere near the bottom. I will double check tonight after work and let you know.

BUt, yes both should be connected

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Dude, where's my rig?

Why do my cars break down when my wife drives them?

[DerJeep]

I think I know what you are talking about, if my memory serves me well.

That "hole" is plugged with a metal plug on my application. Stock in my case. I would guess that yours fell out.

I know that the warm air, from the choke stove, is passed into the carb, from the choke housing, through one of the mounting posts. I do not know if vacuum is used to suck the warm air into the choke, but if it is, then you are suffering from a vacuum leak due to the unplugged hole and this might explain some of your other problems.

I would say, plug it up and make sure it is air tight.

[This message has been edited by DerJeep (edited January 10, 2001).]

[Ralph]

I went out and checked just to make sure, because I was wondering what you were writing about.

I guess there is a place on my choke thermostat housing for a second port; however, on mine the lower port is blocked or has never been drilled out. Also, it doesn't point directly down but is at a slight angle towards the rear (and immediately below the port which has the manifold heat tube connected).

The heat tube is just that and doesn't draw vacuum. The plate with two holes on the intake manifold has a hollow coil underneath it, which is nothing but a coiled metal tube that goes in one hole and comes out the other, so you transfer heat (not pressure) from the interior of the manifold to the carb.

The thermostat housing is a sealed unit; in fact, it originally came with tamper-proof screws that I had to drill out in the course of a complete carb rebuild.

So the only thing I can think of is that the hole in yours is meant to release heat. Why don't you try plugging it and see if that helps your cold start problem?

Also, keep in mind that this is an integrated choke which uses both electric current and heat for its operation.

[christopher]

I think you are right, that it should be plugged and that mine must have fallen out. now to find something that will plug it.

[Ralph]

Sheeeeoooot, just a wad of bubble gum ought to do it.

Actually, that's not too far off the mark. Try something you can get out, just in case it doesn't work, but if you want to make it permanent just get some of that twin-strip epoxy putty and stuff it in the hole.

[Coley]

That's what that hissing sound is!
I have the same thing. Been bugging me for months. Just found it while fiddling with the choke cuz' it's idling on warmup extremely fast (and long).

Yet another item on the to-do list.


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Daddy's Ice Cream Truck (3 yr old daugter named it)
360 727 NP229
Totally stock
"You're obsessed with that thing!"

[This message has been edited by Coley (edited January 11, 2001).]

[christopher]

yes, the hissing sound. so this is happening to others also. what is the scoop? is this hole for some kind of setup used on another vehicle and not on ours? the choke isn't supposed to draw in cold air, thats why there is a gasket on the choke housing. sounds like putty should do the trick. is there any kind I should by that won't burn or dry up if I put it in the hole?

[Coley]

christopher,
Still not completely sure of where the hole is exactly, just jabbed my finger around and felt around the carb with the air filter assy. on. Does it get too hot in that area for a rubber plug? I was thinking of heading to the hardware store and looking for some sort of magic rubber plug. I found well nuts there, so I figure I can find anything.

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Daddy's Ice Cream Truck (3 yr old daugter named it)
360 727 NP229
Totally stock
"You're obsessed with that thing!"

[Coley]

christopher,
I did the Haynes test to check the elec. choke by using a jumper wire from the batt. terminal. Broke.
Just for giggles I checked for juice at the wire as well, to see if I could just get away with replacing the heater. Nope. Nada.
Then I turned over the big ol' wiring loom near it and saw where every wire had been spliced and taped back together. Rats.
I did manage to plug the hole in the choke with a well nut and screw, though. It was all I had on hand.


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Daddy's Ice Cream Truck (3 yr old daugter named it)
360 727 NP229
Totally stock
"You're obsessed with that thing!"

[christopher]

coley,
check to see if the wire is connected to the oil presure switch. it's right asside the oil filter. one wire for the oil pressure guage and next to that is one for the choke heater.

[Ralph]

Here's what that tube in the intake manifold looks like:
http://cgi.ebay.com/ebaymotors/aw-cgi/eBayISAPI.dll?ViewItem&item=542999396

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J ust
E mpty
E very
P ocket

[Coley]

christopher,
I did some more testing. The circuit the choke heater is on was wired wrong. The blue and red\white wires on the starter relay were crossed, and the choke heater wasn't getting any juice with the ign. at any position.
I also plugged the threaded hole on the choke, and it seems to work a lot better.

Ralph,
Thanks for the pic. My setup is different, I believe. My two heat tubes from the manifold are still intact. One goes to the back of the carb, and the other goes to the choke.


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Daddy's Ice Cream Truck (3 yr old daugter named it)
360 727 NP229
Totally stock
"You're obsessed with that thing!"

[christopher]

coley,
I tried to plug the hole but am having trouble finding a plug that will work. what size well nut did you use? mine seems to idle better whan I plug it with my finger. I still wonder what the hole was for?

[Coley]

I "good-enuff" plugged it with a 5/8 well nut with a plastic push pin shoved in it! It ain't pretty or air tight-I still hear a little air escaping-but it'll do for now until I can get a proper plug. I had to make do with what I had lying around. I'm sure you can go to a hardware store and find something that'll actually screw into it. Put a little rubber doughnut gasket on it, and you'll be good to go.

Have no idea what the hole is for. I'm sure we'll stumble across it by accident. Gonna check haynes out, see if I can catch a clearer pic of the choke n such..

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Daddy's Ice Cream Truck (3 yr old daugter named it)
360 727 NP229
Totally stock
"You're obsessed with that thing!"