Update - Tune Parts are In - - Now What???

[Zilverado]

Originally Posted by xtreme80

Occasionally it will leak to the exterior, but mine was leaking down into the carb, thus dumping more fuel in it than it should be.

Okay, so that certainly could be my problem. I assume you are talking about the upper gaskets in the carb - not the carb to intake gasket?

Originally Posted by xtreme80

The best way I can describe a rich smell, is that it smells a little more like gasoline than regular exhaust fumes would. It's not going to smell like gas it being poured out, but it will have a hint of that smell... if that makes sense, lol.

Makes sense and yeah, I'd say that kinda describes it.

So, maybe I'll try and get all the identifying information off the carb tonight, and hit the parts store tomorrow. Maybe I'll pick up the fuel pump just in case. I can always return it.

Thanks Man.

[xtreme80]

Okay, so that certainly could be my problem. I assume you are talking about the upper gaskets in the carb - not the carb to intake gasket?

Yours may be different...

But the carb should have two main gaskets inside. It's got a bottom plate(butterfly plate), a top plate, and the main body. There should be a gasket between the bottom and the body, and one between the top and the body. Mine was leaking from, I believe, the bottom gasket. Over time that stuff just wears out. Like I said, a full rebuild isn't necessary, just replace the gaskets, float, and accelerator pump spring and sleeve, and you should be good to go.

Edit to add:

The number on your carb will be on the main body, and it gonna be like 10 digits long, and SHOULD end with either a 2 or a 7. That last number is the main identifyer. When you get a kit, make SURE they ask you for that number, because the idiots at the parts store here just walked back and grabbed the first kit he saw, before I had a chance to give him the numbers. Turns out he was wrong.

[Zilverado]

OK, so I went and looked for the identifiers.

On the right side behind the throttle plate was "Rochester Quadrajet" of course.

Then there was number plate that read (I think)

17086249
2255 JLJ not too sure about the last J - it was not too clear.

But no 2 or 7.

Actually looking at the schematics that were posted earlier, the carb looks more like a E4ME not M4ME. I say this because of how the vaccuum line to the choke pull off comes out of hte carb in a TEE like mine.

[Ivan D.]

Q-jets have two big plugs under the fuel bowl that are notorious for leaking all of a sudden, when that happens those apparently leak fuel right down the intake cause a rich condition. Now, I have a computer controlled carb but my truck don't have a computer, so I was suggested that even tho those carbs default to very rich condition when a computer is not hooked up my problem with crappy gas mileage and bad idling might be actually in those plugs leaking. So this morning I tore down my Q-jet, just to find that even if those plugs failed (and they didn't) there's no way in hell they leak down the intake, as the carb's base plate covers them completely - the void below them would fill with gasoline, but that's where it'd all end. I don't know how older models are built however, so there might actually be a hole in the base plate allowing the plugs to leak down the intake, I'd suggest pulling the carb and taking it apart.

Oh, and for the record, my crappy idle is cause by a lean condition, as for whatever reason my primary rods are 0.055" diameter, which is way too fat for the 0.074" jets when idling. Also because I have the electronic carb I'll never be able to get it tuned right, so for now it's getting replaced by a Holley 4165 and I'm gonna be rebuilding a friend's early '70s Q-jet, much better cause of no emissions crap.

[Ivan D.]

Originally Posted by Zilverado

17086249

it's an '86 non-California carb for a Pontiac with an stick tranny

Actually looking at the schematics that were posted earlier, the carb looks more like a E4ME not M4ME. I say this because of how the vaccuum line to the choke pull off comes out of hte carb in a TEE like mine.

It's not an E4ME carb, those are computer-controlled (like the POS my truck runs) and yers don't have a plug for the computer wiring. See that cone-shaped dome-thing in the front right corner of yer carb's top plate? That's where the plug goes, ya don't have plug so it ain't an electronic carb, which is actually better.

[Zilverado]

Originally Posted by Ivan D.

it's an '86 non-California carb for a Pontiac with an stick tranny...

So what's that unit doing in a '86 Canadian truck with an automatic???

As for the number - - did I get it exactly right?

[Ivan D.]

Originally Posted by Zilverado

So what's that unit doing in a '86 Canadian truck with an automatic???

As for the number - - did I get it exactly right?

Hey, I have a Buick electronic carb on my truck, so what can I say? Have yer truck ever had the engine replaced? Or maybe some previous owner swapped the carb? As for the number, yes, ya got it right, where do ya think I got all that info about it

[xtreme80]

Ivan did mention something I forgot to mention. Like he said, the Q-Jets are notorious for the fuel well plugs leaking, and on alot of models, this will dump fuel into the intake. You might not be able to tell if they are "bad" or not, but it might be wise to put a little bit of JB weld on the plugs while you have it apart.

[Srubydo1986]

Originally Posted by xtreme80

Ivan did mention something I forgot to mention. Like he said, the Q-Jets are notorious for the fuel well plugs leaking, and on alot of models, this will dump fuel into the intake. You might not be able to tell if they are "bad" or not, but it might be wise to put a little bit of JB weld on the plugs while you have it apart.

hmm i wonder if that what happen to my chevelle back 3 years ago i just yanked it off and through another one on. (dont know how to rebuild plus it was from an 80 cop car.

[Zilverado]

Thanks so much guys - I appreciate all the help and suggestions. I just found my Service Manuals for this truck, but of course, the Unit Repair Manual - which addresses all the carb types - does not list the 17086249...

Oh well, like I say, I'll pay the parts store tomorrow and see what they have for me.

[Ivan D.]

Originally Posted by xtreme80

Ivan did mention something I forgot to mention. Like he said, the Q-Jets are notorious for the fuel well plugs leaking, and on alot of models, this will dump fuel into the intake. You might not be able to tell if they are "bad" or not, but it might be wise to put a little bit of JB weld on the plugs while you have it apart.

Yeah, I like that part about my carb that these plugs are sealed off by the base plate, but that's about the only thing I like about it. When I get the other Q-jet from my friend's dad I'm gonna try to put my base plate on it, so I end up with a non-emissions Q-jet that's near bullet-proof.

[Malo83]

Originally Posted by Eyegore

This is a great thread first of all. Malo83 I have a question for you.. if the engine runs cooler (I live in phoenix so we have them set to run cooler because of the heat) can this effect the choke? I can't my 86 to pass emissions and I believe that this may be the culprit. How do you fix the choke heater malfunctioning?

Tom

By running cooler are you running a 160,180* thermostat?? Are you running an elect. chock or hot air heated off the manifold?? I live here in the central valley of Cali and it gets in the 100's during the summer so I run a 180* thermostat year round and my Qjet has the elect.choke, but have not failed my bi-annual smog check yet(knock on wood) which are the toughest in the land. So no I don't see a cooler running engine affecting the choke except on a cold start. Since your running cooler do you take the truck out and get it hot before your smog test?? unless you have a gross polluter a good tune up,oil change and high speed run down the highway prior to the test you should have no problems passing, I base this on the info you provided.
John

[Eyegore]

Yes I have a electric choke, I believe it is set wrong though. When I first start up it idles very low, but after its warmed up it idles a lot faster, sometimes to fast, I have to tap the gas pedal to slow it down. So how do you adjust electric choke? I read earlier in this post how to adjust the mixture, but now i want to set the choke, idle, and mixture. i'm also going to use some carb cleaner and check inside to see how dirty it is and change the fule filter.

[xtreme80]

Originally Posted by Eyegore

Yes I have a electric choke, I believe it is set wrong though. When I first start up it idles very low, but after its warmed up it idles a lot faster, sometimes to fast, I have to tap the gas pedal to slow it down. So how do you adjust electric choke? I read earlier in this post how to adjust the mixture, but now i want to set the choke, idle, and mixture. i'm also going to use some carb cleaner and check inside to see how dirty it is and change the fule filter.

The choke will have 3 phillips screws holding it in place on the side of the carb. Loosen those 3 (just enough to turn the choke) and turn it counter clockwise to open it up a little bit more.

Mine's open almost all the way on my edelbrock, and I'm in AZ too.

[Eyegore]

xtreme80 is it suppose to be closed when cold, sorry I cannot recall my basic carb setting or is it open cold and closed when warm?

[xtreme80]

It's been a while since I messed with mine, but from what I remember, it should be open when cold. At least mine ran better when it was cold with it open.

[Eyegore]

My problem is gettig past stupid emissions with it. I going to follow the advice earlier in this thread and clean and readjust, resetting everything. Thanks I'll check back tomorrow if i need further advice.

Thanks

[Ivan D.]

Believe for a Q-jet that's otherwise set up right the choke needs to be cracked open just as much so the gap between the rear edge of the flapper and the edge of the tower is about 1/4" at the turn of the ignition key.

[Zilverado]

Originally Posted by Eyegore

xtreme80 is it suppose to be closed when cold, sorry I cannot recall my basic carb setting or is it open cold and closed when warm?

Looks like someone hijacked my thread...

Chokes are typically closed (choking off the air) when the engine is cold. Wide open once the engine is hot.

By "closed" we mean "mostly closed". Like Ivan D said - about 1/4" cracked open at start-up - although I've seen less, like 1/8" or even 1/16" - whatever your engine likes.

As for me, picked up a carb kit, new float and choke pull-off today. See if I get around to tearing into it tomorrow.

[xtreme80]

Good luck! Make sure you post back here and let us know how it went!

[Eyegore]

Sorry zilverado was just trying to get a little info.

[Zilverado]

Originally Posted by Eyegore

Sorry zilverado was just trying to get a little info.

Hey - no worries man.

I just find that by starting a new thread for a specific (yet similar) issue, you can sometimes get more feedback. Folks that have read my thread and feel they have nothing to contribute, may stop reading my thread. These same people however, may have good input for your specific issue, but they never see it, because they've stopped reading my thread - - makes sense?

Not sure if that's how it works, but that's the theory I apply...

[Zilverado]

So, I replaced the choke pull-off with a new one (which actually holds vaccuum), but as I suspected, nothing changed in the engine performance. I also have the carb rebuild kit, so that will be the next step.

I ran the engine for a bit this morning, and noticed that as it was beginning to stall, there was liquid fuel actually splashing up at the top of the carb - on the top of the air horn assembly - between the choke butterfly and secondary throttle butterfly. When the engine finally died, it spit fuel up through the butterflies - - so she's definitely drowning in gas, no worries anymore about lack of fuel delivery (i.e. fuel pump).

So does this point to any specific issues within the carb body? Like I say, I am planning to tear into the carb as soon as possible, but it may be a few days yet.

In addition to the rebuild kit I also purchased a new float.

[Ivan D.]

float level is too high, so yer needle don't shut off the gas flow even when the fuel bowl is full. Also check jets, something might be plugged with crap and dirt.

[Zilverado]

Originally Posted by Ivan D.

float level is too high, so yer needle don't shut off the gas flow even when the fuel bowl is full. Also check jets, something might be plugged with crap and dirt.

Are you saying that the needle in the float bowl is not seating properly - this should be solved by a rebuild, right?

I am so looking forward to getting back under the hood and tearing into this. But for today, I'm stuck doing some house renovations (drywall, ceiling tiles, etc) in our laundry room - - just another of TOO MANY projects.

Thank-you soooo much for all the help so far.