Idle Issue

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Dizzydean

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Good Day, I have a 67 with the holley 1bbl that was sitting for about 20 or so tears. The person i bought it from took out the tank and ran a chain inside to break up varnish then steamed it. It runs ok with the choke but after it warms up it will only run with slight pressure on the throttle. Will not idle. I replaced everything from a kit and throughly cleaned all holes and parts also I put 2 inline filters to make sure fuel was being cleaned. Its a little better but same issue also sounds like a miss when running. No vacuum leaks. Starts right up just wont idle. Hard to drive with 2 feet. Appreciate any help. Thanks.
 
I think I would start with a good tune-up. Check the compression and go from there. Plugs, wires, cap, rotor, etc. The parts are cheap. After that, it may just need to get some miles under its belt to work out the kinks.
 
Have you done a cylinder kill test to see if one hole may not be producing? Also if your carb has a poly-nitrofill foam float it could be too dense and need replacing.
 
Good Day, I have a 67 with the holley 1bbl that was sitting for about 20 or so tears. The person i bought it from took out the tank and ran a chain inside to break up varnish then steamed it. It runs ok with the choke but after it warms up it will only run with slight pressure on the throttle. Will not idle. I replaced everything from a kit and throughly cleaned all holes and parts also I put 2 inline filters to make sure fuel was being cleaned. Its a little better but same issue also sounds like a miss when running. No vacuum leaks. Starts right up just wont idle. Hard to drive with 2 feet. Appreciate any help. Thanks.

A Freudian slip?

Tune up couldn't hurt but try this just for fun.
Turn the idle screw all the way in and count the turns it takes to get it there.
Take the screw out and use a compressor, canned air, a small hose or anything you can find to blow air through the idle circuit.
Put the needle back in, bottom it lightly and back it out 1.5 turns

See if that fixed or changed it any.
 
Thanks for all the advice so far. Im trying not to get to involved until the paperwork clears but i did check all the wires they look new so i went to the coil and swapped out with one i have but maybe its to HP its an msd regular not the big one. No change. Checked the cap and found a bent rotor. I tried to to straighten it but now its worse so today i will swap out the dist with a spare i have to make sure the point gap is correct and put on a new cap and rotor. Update to follow. Yeah looks like I slipped on the year part (maybe).
 
Got the dist replaced with quality point cap n rotor. Found a scrape on the inside of the old cap so Im thinking they put it on askew which would explain the bent tab on the rotor. It started right up and actually ran for about 3-5 mins then the choke let off and it still couldnt keep running without light taps. Really at a loss now :???:
 
You can try;
- Richen up the mixture by turning the idle mixture screw out half a turn orso.
- Increase idle speed of the engine. Any idea how much rpm it is running when it does?
- Hook up a vacuum gauge and report back the number you're seeing on the gauge. After 20 years, one or more piston rings could be stuck to the piston and create a lousy engine vacuum. Also, bad timing adjustment can create low vacuum too, as a few other things can.
 
Sounds like you have some deposits in the idle circuits. May try soaking the carb body in lacquer thinner with all the small parts removed and hit with high pressure air. Double check your float level. This crap fuel we get stops up the idle circuits on my Honda clone engines when they sit a while and do the same thing unless you run partial choke.
 
Sounds like you have some deposits in the idle circuits. May try soaking the carb body in lacquer thinner with all the small parts removed and hit with high pressure air. Double check your float level. This crap fuel we get stops up the idle circuits on my Honda clone engines when they sit a while and do the same thing unless you run partial choke.

Yep, or too low an idle.
That's where I was going with the idle mixture screw.:D
But you knew that already.
 
Checked the plugs they were all misgapped and played with the timing brought it closer to the zero mark and it lowered the idle considerably also shut down sooner so Ill run it up a bit today. I think Im going to get another carb rather than playing with this one at least that way I have a back up. Would lose valves cause this by any chance? I can hear a miss when its revving while the chokes on not bad but noticable and so far thats the only thing I havent tried. I looked under the car and hoses ahve been replaced at the tank and the strap bolts have marks where they were taken off so I feel confident the previous owner did take off the tank for cleaning. Thanks again for everyones help. :rock:
 
Did the valve adjst and still having the same issue. Replace the carb? is all I can think of. This is the dirtiest engine I have seen in a long time the oil looks like carbon.
 
Looks almost as bad as my '62 /6! The deposits are from crappy oil (old Quaker State and Pennzoil that used PA crude oil bases in the 60's and 70's was well known for a lot of this type of crudding up), and perhaps limited oil and filter changes, and a lot of short in-town driving. The carb may also have been leaking after shut off and gotten gas into the crankcase and oil repeatedly.

This is a good indication that your valve guides have crud/varnish in them; this will cause sticking valves (/6's have low valve spring pressures so the valves stick easily), poor running, and misses. Since the car will idle, start it up with the valve cover off. The oil won't do any thing but dribble off of the rockers. Look at the rockers from the front of the engine and study the closing motion on each one. If one or more of them looks 'lazy' when closing, you have gunk in the guides.

To clean the guides, use the rope trick to hold the valves closed and remove the valve springs on the cylinders, one cylinder at a time. (Ask if you don't know the rope trick....) Work some carb gum cutter down each guide work them up and down 'till they are free. Put in new valve stem seals while you are at it.

This won't solve any carb or ignition related issues but may cure your misses. And setting the valve lash won't be reliable and consistent with sticky valves. This is just something I would do due to the gunk on the inside.

I would also not try to clean this crud out in any fast way. There is just too much and you may end up with a pan full of crud, blocking up the oil pickup from time to time. BTDT! Just use some good detergent motor oils for a while and change it and the filter a lot for a while.

I also suspect your timing chain is well worn with this kind of oil abuse. Another good long term project.

Set you timing at +5 BTDC or so as a starting point, not 0.

The suggestions on the carb idle circuit may well be spot on. Have you checked the float level while running (wet float level)? Remove the economizer valve (the thing on the bolw with the triangular cover), and idle the car level. The fuel level should be 11/16" below the flat top of the hole that the economizer valve came out of.

Your poor running symptoms after the choke drops off may have something to do with the ignition coil, points, or ballast; a weak ignition can do this, although it should just bog and have a very poor idle,not quit entirely. The points gap should be at about .017-.018". The ballast should be about 0.6-0.8 ohms cold. These are easy things to check.

Have you done the compression testing yet? And have you actually measured vacuum while idling? In other words, how do you know you don't have a vacuum leak?
 
Looks almost as bad as my '62 /6! The deposits are from crappy oil (old Quaker State and Pennzoil that used PA crude oil bases in the 60's and 70's was well known for a lot of this type of crudding up), and perhaps limited oil and filter changes, and a lot of short in-town driving. The carb may also have been leaking after shut off and gotten gas into the crankcase and oil repeatedly.

This is a good indication that your valve guides have crud/varnish in them; this will cause sticking valves (/6's have low valve spring pressures so the valves stick easily), poor running, and misses. Since the car will idle, start it up with the valve cover off. The oil won't do any thing but dribble off of the rockers. Look at the rockers from the front of the engine and study the closing motion on each one. If one or more of them looks 'lazy' when closing, you have gunk in the guides.

To clean the guides, use the rope trick to hold the valves closed and remove the valve springs on the cylinders, one cylinder at a time. (Ask if you don't know the rope trick....) Work some carb gum cutter down each guide work them up and down 'till they are free. Put in new valve stem seals while you are at it.

This won't solve any carb or ignition related issues but may cure your misses. And setting the valve lash won't be reliable and consistent with sticky valves. This is just something I would do due to the gunk on the inside.

I would also not try to clean this crud out in any fast way. There is just too much and you may end up with a pan full of crud, blocking up the oil pickup from time to time. BTDT! Just use some good detergent motor oils for a while and change it and the filter a lot for a while.

I also suspect your timing chain is well worn with this kind of oil abuse. Another good long term project.

Set you timing at +5 BTDC or so as a starting point, not 0.

The suggestions on the carb idle circuit may well be spot on. Have you checked the float level while running (wet float level)? Remove the economizer valve (the thing on the bolw with the triangular cover), and idle the car level. The fuel level should be 11/16" below the flat top of the hole that the economizer valve came out of.

Your poor running symptoms after the choke drops off may have something to do with the ignition coil, points, or ballast; a weak ignition can do this, although it should just bog and have a very poor idle,not quit entirely. The points gap should be at about .017-.018". The ballast should be about 0.6-0.8 ohms cold. These are easy things to check.

Have you done the compression testing yet? And have you actually measured vacuum while idling? In other words, how do you know you don't have a vacuum leak?

As soon as I saw that picture I said "looks like Pennzoil to me" before I even saw what you wrote. :D
 
This is how my 64 225 looked. 97,000 miles and off the road since 82. One pic is the bottom of the oil pan and the other is self explanatory. I'm in the process of a complete rebuild.
If you are not going to go that far, you should definitely take the rocker shaft and rockers off and clean them. The oil holes in my shaft that feed the rockers were completely clogged and there are oil passages in the rockers also.
 

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As soon as I saw that picture I said "looks like Pennzoil to me" before I even saw what you wrote. :D
Yup. I used to have to have to read a lot of MIL specs and I found one on motor oils once; it prohibited the use of high parrafin content crudes, and that included a lot of the PA crudes. My 351C was that way.... the hood on the original Torino had Quaker State stickers all over the underside of the hood when I pulled it from the j-yard!

And KrazyKuda shows a good pics of where all that gunk goes.... my /6 pan looked just like that. If the OP does any internal cleaning, be ready to get the pan off to get that stuff out. Unless someone knows of a way to get it out via the oil drain hole....maybe flush with gasoline being veeeery careful AFTER removing the battery from the car....?? (Not a good procedure for smokers!)
 
Thanks for all the help and advice guys. Still #1 priority is getting the paperwork in order. After I will probably just replace the motor and rebuild this one. Easier for me. This car still has the white washington plates on it last registered 1981. Its in pretty good cond.
 
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