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Help...225 won't idle at low idle only very high idle
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Author:  HookedByA62Valiant [ Sat Mar 31, 2007 6:31 pm ]
Post subject:  Help...225 won't idle at low idle only very high idle

I'm at the end of my knowledge and wits. It all started when I (accidently) poisoned my car with bad gas. Coughing, sputtering, dying. Finally syphoned the gas out of the tank. Replaced the fuel filter, poured in 2 different types of gas treatment (Heet and STP). I found that spraying WD-40 made it run much better so I bought some liquid WD-40 and poured a quart in with fresh gas. Well now I can drive it around the block and that's about it. It dies anytime I let the idle down. Today I replaced the carb base gasket and even the fuel pump. With a screw driver holding the idle high it will run but it won't stay running at low idle.
Oh yeah, I also blew air back thru the fuel line into the tank and checked the line between the fuel pump and the carb, no blockage there either.
Any suggestions?

Author:  SlantSixDan [ Sat Mar 31, 2007 7:16 pm ]
Post subject: 

Heet, STP, and WD-40 are not what is needed to clean a system that's been contaminated with bad gas. (Heet and STP "fuel treatment" are never necessary in almost all climates, including yours. Waste of money and liable to make things worse rather than better. Gallon of WD-40: BIG waste of money.)

Depending on the nature of the "bad" gas (was it watered-down? Old and varnished? Contaminated with diesel fuel or something else?) you may need to drop the tank and replace the filter "sock" on the end of the fuel pickup pipe (sounds like you'll get away without that this time), and you will definitely need to tear down, clean and rebuild the carburetor with a good kit.

Author:  HookedByA62Valiant [ Sun Apr 01, 2007 8:12 am ]
Post subject:  I was reading the Petersons Repair Manual

Last night I was reading the Petersons Repair Manual and it described a couple of things correctly that are going on: flame back thru the carb as running lean, which it is, not a very big flow of gas thru the filter and it suggested that if water has gotten into the tank the "sock" filter could be wasted. That makes sense and your reference to the sock maybe right on after all. The gas came out of a car stored for over 10 years indoors. Not sure specifically if it had water or if it was just old. I guess I'll be draining the tank again and this time removing it! The question is where to get a new sock?

Author:  slantasaurus [ Sun Apr 01, 2007 8:38 am ]
Post subject: 

Year One and Paddock both have new socks.

Author:  SlantSixDan [ Sun Apr 01, 2007 10:48 am ]
Post subject: 

Nearest Chevrolet dealer ought to be able to supply you with a new "sock". See this post.

Remember that lean running like this what you're describing can be caused by one or more factors upstream of the cylinder itself! Working backwards: Sticking intake valve(s), vacuum leak(s), clogged carburetor passage(s), clogged fuel filter, plugged filter sock. But remember that fuel demand is lower at low RPM than at high RPM, so if you can make the engine run at all under 2,000 RPM, then the in-tank "sock" probably isn't the main factor at work.

I really think you're going to need to do a thorough cleanout of the fuel system (tank, lines), put in a new sock, and rebuild the carburetor, then see how things go. Don't buy a "rebuilt" or "remanufactured" carburetor!

Author:  Chuck [ Sun Apr 01, 2007 11:10 am ]
Post subject: 

One thing I would try first is to remove the air screw from the carb and blow some compressed air through there. I have had similar problems that were cured by blowing that passage clean.

Author:  HookedByA62Valiant [ Sun Apr 01, 2007 11:38 am ]
Post subject:  Ok.

Other information I haven't told you...
I have a cheap glass fuel filter and I can see the gas in the filter. What makes me think that the sock maybe a plausible solution is that I see a very small stream of gas and sometimes bigger splashes of gas. (Which is why I bought a replacement fuel pump). When I put in the new pump it filled the filter pretty quickly then after a few minutes of running it petered out to the same as the original fuel pump.
Several times during the process, I've sprayed Carb cleaner in the carb, around the carb and manifold gaskets and EGR valve. I knew previously that it had some leaks but before the bad gas it would idle fine, even at a fairly low idle. Still, since the carb cleaner made the idle increase I replaced the carb base gasket and tightened the manifold retainer screws.
Also, I have a Super Six setup and openned up the top of the carb to see inside. No water, no evidence of anything stuck. The suggestion about blowing into the mixture screw, I haven't tried.

Author:  Slanted Opinion [ Sun Apr 01, 2007 11:59 am ]
Post subject: 

Once upon a time my Valiant fuel tank became contanimated with junk. It gave me the same symptoms... ran at high idle, died at low idle (couldn't keep it running at idle without treadling the gas pedal).

Solved the problem by changing the fuel filter (as you have), then disassembled the carb and cleaned out all the junk that was in the bottom of the float bowl.

Ran great after that.

-Mac

Author:  Davey [ Sun Apr 01, 2007 2:54 pm ]
Post subject: 

I had a 66 Corvair that ran exactly as you described. I did everything I could think of, including putting kits in both carbs. What fixed it was doing what Chuck suggested: Very carefully run the air screws in counting the turns until they seat. Then remove them and blow a shot of compressed air into the hole. Doesn't have to be 100psi, just a shot of average shop air. Then replace the air screws and screw in until they seat. Back them out the number of turns you counted and try it. You may be amazed. Davey

Author:  Davey [ Sun Apr 01, 2007 3:00 pm ]
Post subject: 

PS, I kept saying "they" because my Corvair had two carbs and thus an air screw each for a total of two. If you have one carb, you'll only have one idle air screw. Davey

Author:  HookedByA62Valiant [ Sun Apr 01, 2007 6:05 pm ]
Post subject:  Next

Ok guys, I pulled the top of the carb off and pulled the floats out and there was some tiny balls of yellowish orange stuff. I cleaned it out, blew out every hole that the carb has! Nothing was blocked. I also backed out the idle mixture screws and blew air thru there also.
It sounds better then yesterday but still won't really idle. I drove her around the block and she died once but is backfiring less. Then it started to idle very roughly for 7 seconds or so and died.

Author:  SlantSixDan [ Sun Apr 01, 2007 9:33 pm ]
Post subject: 

Not nearly a good enough carb cleanout job. You need to _clean_ and _rebuild_ it. That calls for a full disassembly, cleaning in carburetor cleaner, etc.

Author:  ROADRUNNER7169 [ Mon Apr 02, 2007 7:14 am ]
Post subject: 

the mopar sock is ns1 but their are 3 dealers with them still

this dealer shows 8 in stock

FAMILY CHRY-JEEP CHADDS FORD PA USA Phone: (610)-558-9010 / (888)-287-2753

this dealer shows about 44 in stock

PORT JEFF CHRY JEEP INC PORT JEFFERSON STATION NY USA Phone: (631)-474-4949 / (631)-474-3939

this dealer only shows one

DRESSLER CHRYSLER JEEP DODGE OF COVINGTON VA USA Phone: (540)-962-2291

Author:  HookedByA62Valiant [ Wed Apr 04, 2007 4:42 pm ]
Post subject:  The Latest Update

Well, it seems to have worked!
I started her right up today and she idled and we drove around with no coughing or backfiring.
After cleaning the carb and blowing out all the opennings (again) and all that she seems to be better now. Thanks for you of your suggestions!!!!

(Now I have to do the same to the other Valiant, I poisoned her also). :(

The Lesson:
NEVER PUT OLD GAS IN YOUR CARS!!! NEVER.

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