lean mixture, low octain fuel, slow idle down until you can throw that eld/ away put your qj back on good luck

 

so, lean my mixture out?

 

not trying to grt nasty, but lean mixture and low octain fuel ,the only reason for run on eld. famous for lean idle .didny mean to pi88 in your corn flakes

 

I know that if you have an auto trans if you dont put it in park before shutting it off it can somtimes help.

 

Engine run on is caused by pre-ignition and the failure of the carb to cut off air/fuel flow.

You may have to add a anti/diesel solenoid. They are available from EDELBROCK and HOLLEY.

 

Richen your idle mixture and try advancing your timing which will raise the idle speed allowing you to turn down your idle screw closing up your throttle plates more. I also run nothing but premium gas, it's worth the extra money.

[ January 13, 2003: Message edited by: dmorris1200 ]</p>

 

Get that idle speed down first. What kultulz says is correct. Set idle speed to 450 - 500 rpm with the solinoid disconnected or at the lowest possible rpm w/out dying, then normal idle speed w/ solinoid on. Most of the time that will solve the problem.

 

Get that idle speed down first. What kultulz says is correct. <hr></blockquote>
KULTULZ never said that the idle was the problem. He said you need to cut-off the air/fuel flow which is not the same thing. If his idle is already set within specs (according to his post looks like everything set to specs) how do you close the throttle plates more? You advance the timing (raises rpm) and then compensate by turning out idle screw. Your idle ends up exactly the same in the long run but throttle plates close more and with the timing advanced a bit and she'll run better. Car's rarely ever run best when set to specs, except late model FI cars. By richening up the fuel mixture that will also help to reduce combustion temperatures which helps.

[ January 14, 2003: Message edited by: dmorris1200 ]</p>

 

KULTULZ never said that the idle was the problem. He said you need to cut-off the air/fuel flow which is not the same thing.<hr></blockquote>

...failure of the carb to cut off air/fuel flow<hr></blockquote>

Well...in all actuality...it is the same thing. When emissions dictated that carbs go lean, this saw the introduction of the idle kick-up solenoids. The fuel mixture ratio was so lean that it led to bad idle and stumbling on tip-in. They raised the curb idle to remedy this. But it caused run-on due to the throttle plates not being able to close properly and fuel mixture still being drawn into the hot combustion chambers.

You can most certainly enrichen the fuel mixture/advance timing to correct the problem. But what if the initial ignition advance causes pre-ignition on load or hard starting? What if the idle circuit enrichment causes excessive exhaust fumes and fouling of the plugs? Remember the early days (70's) of the first emission systems?

If he does these adjustments and they cause more problems than they cure, the idle solenoid will allow the idle to be set where desired with the engine in whatever state of tune desired. Once the ignition voltage is removed, it will allow the throttle plates to slam shut, eliminating the problem.

Now, he could also be experiencing throttle plate/linkage bind, not allowing the throttle plates to close entirely also.

Aggravating S.O.B. ain't I?

 

Again correct kultulz. Remove the carb from the engine, turn it over, back off the idle screw until it clears the throttle linkage. Check the throttle plates by holding a flash light at the opposite end of the throttle plates. If you can see light around the edge of the plates you may have to adjust them. Loosen the 2 throttle plate screws on each plate and tap them w/ the handle end of the screw driver while holding the throttle shaft shut. They will self adjust. Retighten the plate screws then adjust the throttle stop screw till the plates just start to open, this will prevent throttle plate sticking from the closed plate position and prevent excessive air from bleeding around the plates. That, in turn, will shut off air/fuel flow and stop run on (dieseling). Check the secondaries to make sure they are closing completely also. Make sure the linkage isnt holding them open.

[ January 14, 2003: Message edited by: 2-manytoyzs ]</p>

 

Well...in all actuality...it is the same thing. <hr></blockquote>
No it is not the same thing, if I can close the throttle plate further without changing the idle saying "cutting off the air/fuel flow" and "lowering idle" are not the same.

When emissions dictated that carbs go lean, this saw the introduction of the idle kick-up solenoids. The fuel mixture ratio was so lean that it led to bad idle and stumbling on tip-in. They raised the curb idle to remedy this. <hr></blockquote>
This all assumes he has a stock set-up for post-emissions with a idle solenoid. He stated he installed an aftermarket carb. He may not even have an idle-up solenoid. The only reason you should need a idle-up solenoid on a aftermarket carb is for air conditioning load. Otherwise the carb should be jetted rich enough without any factory M/C solenoids, etc. to not require a idle-up solenoid. I have been doing carb swaps for over twenty years and have never used (needed) an idle-up solenoid except to provide a idle increase to handle A/C load. Also doing state inspections for many years one of the first things I learned is as soon as any old car(pre-fuel injection) passes emissions testing to bump up the idle a bit and richen the fuel mixture. Also anyone else in the field that I have ever worked with has agreed that the settings needed to pass emissions are definately not the settings you want to make the engine run it's best. They kill the poor things just to reduce emissions. You can see right in the pictures of my carb that there is no idle solenoid. Why, cause I don't need it because like you said it was just a crutch from the car manufactures to compensate for all the detuning they did for emissions. And since I've had my license and been working on street rods I have never once found a car that I couldn't run with more advance than factory spec and couldn't richen up to run better. Richer mixtures lower combustion temperatures, reduce pinging, and can actually if not done to far can reduce gas mileage (have read testing on the mileage issue). Stock is one thing, but once you can all the factory emissions garbage it's a whole different ballgame. Maybe before you tell him to lower his idle till he stalls out stopping you should ask him if he retained any emissions hardware and if he has a idle-up solenoid. Like I said originally and this was all I said, lowering the idle and stopping the air/fuel ARE NOT THE SAME as I can prove that I can close the throttle plates more without lowering the idle. That is all, whether you agree with that method is a diferent issue but I know what's been working on the many, many carbed cars that I've been running on the streets and racing 1/4 mile since I've been driving and doing this for a living. Heck I used to have friends that would regularly come to my job so I could lean out there carb and retard the timing enough to pass inspection tests and then as soon as they're passed I'd bump the timing back up and reset the carb and away they would go till the next year. Now I would think if this wasn't working I would have a lot of pissed off customers with fouled spark plugs.

 

EW-W-W-W-W-W-W-W-W

...sheesh...

Retaining water this week? I will just leave it alone...

 

Sometimes choke problems can do this.. at least it did on my car when the choke didn't work too well... make sure the choke isn't staying closed

 

Correct again kultulz!

 

Correct about what? Do you even have a point?

...sheesh...

 

Yeah, I didn't think so.

 

beotch lmao

[ January 14, 2003: Message edited by: crazy larry ]</p>

 

Well........my point is.........In all my 35 years (in the business), and all my boats, m/cycles, cars, trucks, rv's, projects, and as a Ford Certified Master electrical, electronics, and driveability Tech, I have learned this......there is always more than one way to get the job done!
HEY Heavy Chevy! Let us know what ya did to solve your problem on dieseling.
Of course..............do the idle thing 1st!

[ January 15, 2003: Message edited by: 2-manytoyzs ]</p>

 

there is always more than one way to get the job done!
<hr></blockquote>
You are absolutely right, my argument though wasn't about the right way or the wrong way.

whether you agree with that method is a diferent issue <hr></blockquote>
I simply stated that to just say to turn down the idle is not the same as cutting off air/fuel flow. You may have meant that I'm sure but often what is written can be interpreted if not written clearly. If you told me to lower my car's idle from 700rpm to 500rpm and I turn the distributor retarding the timing til I'm at 500rpm did I do what you said? Yes. Maybe not what you meant I'm sure but I did accomplish what you said. I also am a college edducated, ASE certified (including L1-Advanced Engine Performance), and spent six years at one of the biggest Ford dealerships in my area when I lived in Jersey. I will also say that most of that means little as at the dealership I worked at one of the most experienced guys there by the time he retired was reduced to doing PDI's and used car preps because the technology had past him by. He was a Ford Certified Master Mechanic. I'm sure you aren't stupid and I never said your opinion was right or wrong just having a little fun picking at how you worded what you said.

 

Originally posted by dmorris1200:
[qb]

(I also am a college edducated)

Is that how they spell in New Jersey? I spent 6 weeks at ft dix back in the late '60s. Glad your back in maine. They might talk funny but at least they can spell.

[ January 15, 2003: Message edited by: 2-manytoyzs ]</p>

 

Originally posted by dmorris1200:
<strong>
just having a little fun picking at how you worded what you said.</strong><hr></blockquote>

just having a little fun picking at how you spell. maybe we'll get into it on another post someday!

We also had a Master tech that didnt keep up w/ the technology at the shop i was at. Doesnt take long to get lost while working on multiplexing problem in a Navigator if your not up to speed.

 

Oh noooo! Are we done? And I was just havin' fun. Man I like a good debate. This is the first good debate I've had on this site in a while that didn't resort to profanity by the second post. Next time I'll be a little more careful on that 'd' key . I actually grew up close to Fort Dix in Monmouth County. When they started giving out pills to residents in case of an attack on the nuclear plant I decided to head north. When I moved up here I got a job at an independant shop right down the road from my house. It's a good shop, honest group of guys, and my boss retired from a service manager position at Ford to buy his own shop. It's nice to not worry about flag sheets, warranty pay, what I can 'M' time and what I can't, but I miss WDS and having access to QC Dealer. Oh well, life goes on.

[ January 15, 2003: Message edited by: dmorris1200 ]</p>

 

ok, guys so I really want to advance my timing and richen my IMS about 1/2 turn? and back the idle off to about what rpm with my foot on the brake and in drive? And also when i had my q-jet on there i removed all that smog crap, saved alot of weight too <img src="graemlins/mwink.gif" border="0" alt="[mwink]" /> What should i set my intaial advance to? Right now, i have it at 6 btdc.

 

Well we never did find out if you have an idle-up solenoid on the new carb but I'll assume you don't for now. Sometimes you just have to experiment to find out where she runs best. I would say turn your mixture screws out the 1/2 turn you mentioned and see if the idle quality improves. I would also set the base timing (with distributor vacuum disconnected and the line plugged) to about 10-12BTDC which will raise your idle speed. Now you can turn out your idle set-screw to bring your idle back down and close your throttle plates more. If she responds better you can repeat this procedure taking the base timing to 14BTDC and see what happens. Remember, if she pings when you accelerate you have advanced too far and need to simply turn back. If you don't experiment you'll never learn. Same thing with the idle mixture. A richer idle mixture will generally smooth out an idle but you can only go so far. The bottom line is you need to learn for yourself where your engine runs best. I can not account for a weak engine, low compression, worn valves, weak ignition, etc. over the internet. Just because my car may run great at 14BTDC doesn't mean yours will. So start playing and HAVE FUN! That's what it's all about.

 

...whew...

I sure am glad you guys have called a ceasefire and have stopped waiving PHD's and factory certifications at the rest of us...