Help! My Satellite is posessed with insanely fast idle speed.

[74Sebring]

Hi all, I sure hope someone can help me solve this mess. I have a 74 Sebring Plus with a 360 4BBL and 727 Trans. The carb is a Carter Thermoquad 6545s. The car idles way too fast and everything i try to correct the problem just makes the idle faster. Tomorrow, my cousin and I are going to rebuild the carb. I really want this TQ to work. I'm a fan of the TQ and hate the idea of an Eddy or a Holley taking its place. I know this carb will perform. Ok, what's been done so far. 1. Ignition timing set to 5 degrees before TDC, 2. All vacuum ports on the carb and intake are either connected to a device or capped off. 3. throttle cable has been lubricated and checked for kinks. 4. idle and mixture screws have been set to a beginning base point (mixture screws gently bottomed out and turned back 1 1/2 turns, fast idle screw gently in contact with the second cam notch, curb idle screw just in contact with cam), 5. there is no electronic solenoid on this carb but there is a vacuum device where that solenoid would be. it seems to do nothing. 6. the vacuum pot for the choke appears to do nothing as well. the vacuum advance on the distributor works perfectly. 7. an entire can of carb cleaner has been run thru already. 8. there are no discernible air leaks (but the car is pretty loud so i'm not positive). I could understand if the idle would hold high but, everything I've done that, according to popular convention, should slow the idle has only increased it. I seriously believe I could drive down an interstate highway without ever using the gas pedal. Any ideas, including chicken sacrifices and voodoo rituals, will be gratefully appreciated. Pics of my car will be posted soon. I've just been losing my mind trying to fix the idle.

Thanks, 74Sebring.
Martin :cussing:

 

[NOSTRT980]

have you tried disconnecting the throttle cable to see if the rpm's come down.

 

[62 Dart Convertible]

Hey Martin

Keepin' it real in Topeka (I'm thinking "Almost Famous" here...I love that movie)

Can only be that too much air is being allowed in to intake manifold at idle.

As NOSTRT980 above says, 1st disconnect throttle cable and back out all idle speed screws (not mixture screws). Still too fast? You sure all vac ports have been blocked? (Leaking brake booster or PCV valve are the most likely culprits.) Still no good? Remove carb and check all butterflies close fully (i.e. none jammed open/broken/loose). If OK, refit carb. Still too fast? I'd suspect a faulty leaking carb base gasket or intake manifold gasket....

 

[Xp29h]

I'll throw this out here...I definitely would do what has been suggested and what you have planned. However, if all fails look at you kick down linkage. I know on my set up, I accidentally hooked it back up wrong when I rebuilt my carb, the rpm just kept climbing to a point. Like you said, I could have driven down the road without touching the gas! Took me a couple moments to figure out and fix. Anyway, good luck!

 

[74Sebring]

Haven't tried that but, I will tonight. Thanks!

- - - Updated - - -

I'm not sure why but, my reply was not complete. First off, Thanks to all of you for the fast response and great ideas! I'll be digging in tonight and, if any of this works, my neighbors will be thrilled to not hear my Satellite roaring like Godzilla in the middle of the night anymore. I guess I'll just have to start doing the occasional burnout so they don't get bored.

 

[62 Dart Convertible]

Good luck!

Please do come back and let us know how you get on...

 

[bandit]

Not familiar with Carter set up but I'll toss this out there. On my Holley there is an adjusting screw to set the secondary throttle plates when secondaries are not engaged. You have to set it from underneath when the carb is off. If set too high you'll have your secondary throttle plates open too much. Good luck.

 

[mopar 3 B]

If you decide to rebuild check the blades and make sure they are closing completely in the bores. Do not attempt to completely remove the screws as they are staked to keep them from coming out and being sucked threw the engine. Also the front blades have a beveled step cut in them. This step should face the inlet side of the carb and align with the idle ports in the front of the bores. If all is not correct here you will have the condition you have described.

 

[YY1]

Spray some carb cleaner at the base of the carb.

See what happens.

 

[74Sebring]

Problem seems to be resolved. I did try all of the suggestions from everyone. Some had minimal effect. The issue proved to be a weird vacuum actuated pot on the right front of the carb (see pics). We timed her as close as we dared, readjusted the idle screws and started disconnecting the throttle cable, minimal effect, the kick down linkage, didn't seem to have any effect, went after the various vacuum ports that were capped off. Hit on whatever this thing is and the RPMs plummeted! I couldn't see it but, it was definitely holding the primaries open just a bit. I pulled the vacuum line off and threaded the pot away from the linkage. i still have to nudge the gas pedal from underneath to get the RPMs down all the way so, I think a throttle cable is still in the future as well as a carb rebuild but, she will finally settle down to about 700 RPMs. It's been a lot of frustration and work but, 850 cfm's of Carter TQ is all worth it. Thanks to everyone again. Your thoughts and suggestions got me moving the right direction. For reference, if anybody is curious, this is a
Carter Thermoquad 6545s.

 

[Xp29h]

Great! Glad you got it!

 

[Ron Ward]

Martin, I'm pretty good with TQ's and I happen to also live in Topeka. If you ever need a hand, I'd be happy to help.

Ron

 

[74Sebring]

That would be greatly appreciated! It's good to have a second set of eyes, especially knowledgeable ones, when I dig into the rebuild. You might see something else that I missed as well. When you get a chance, send a PM with what works for your schedule and i'll see if I can match up. Thanks again Ron!

 

[62 Dart Convertible]

Is that a vacuum actuator for increasing idle speed for A/C?

Glad you worked it out Martin!

 

[74Sebring]

I think so but, I have found nothing that verifies that assumption. It makes sense as the car came with A/C. The previous owner removed all of the A/C components under the hood though. GRRRRRRRR! It's TDH here for a car with no A/C. Oh well, less weight makes it go faster.

 

[62 Dart Convertible]

It's TDH here for a car with no A/C.

TDH? Too Damned Hot?

 

[74Sebring]

Yes sir! Heat indexes here have been as high as 118 degrees this summer.

 

[62 Dart Convertible]

You ain't gonna get much pity from me mate. I love the hot weather, and am suffering through the southern winter.....

 

[74Sebring]

I think we are finally getting into cooler weather. Mid 80's this week with lows in the 50's. Soon it'll be in the teens for high temps with snow everywhere. I need to hustle up and get my list done before it gets too cold now. What's on the agenda? New Hedman headers, Weiand intake, Comp Cams kit (Jegs part # K20-223-3), new pistons (Jegs part # KB107KTM.STD), cam bearings, rod bearings, main bearings, repaint the engine, power wash and paint the engine bay, heater core, blower motor, heater control valve, new tie rod ends, idler arm, pitman arm, front shocks, rear air shocks, fan shroud, new console, new brake hoses, wheel cylinders rebuilt, flush out all old brake fluid and bleed the system. I'm sure there's more but I can't remember it now. I have a feeling I won't make it.