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Topic Review (Newest First)
08-28-2012 06:24 PM
s10mikey if you have any adjustment on your trottle cabel try to see how tight it is,,
08-28-2012 03:29 PM
osweezea
Quote:
Originally Posted by DoubleVision View Post
First thing I suspect is the mechanical timing advance is sticking open. Don't matter what springs or weights are in it either. After a while if they get gummed up, and they all do, they will stick open and cause all kinds of headaches. What carb are you using? Because of how it's acting I don't think you have a vacuum leak, but it is something to check. If the carb is a 4 barrel the secondaries could be slightly sticking open which also happens at times as well. I used to have a Demon carb that had a bad habit of the secondaries sticking slightly open and I had to sand the burrs out of the base plate to stop it. See if you can get it to idle high again then check the secondary linkage to see if it's open any.
Here's the details from the for sale ad.

AMC360 V8, bored .030 over, All work done by Engincraft in 2008, (less than 2000 miles on motor.)
Edelbrock Proformer intake
Comp Cam - Intake @ valve 496, Exhaust @ valve 521
Roller Rockers
Holly 670 Truck Advenger, MSD.
Fenderwell headers, 3" flowmaster exhaust.

The Holley is still on it.
I did check the secondaries, and they may have been stuck open just a touch. The linkages were not moving the secondaries at all when the motor was not running. So I reached down in there to see if the were frozen and it did snap shut I think once I put a little pressure on it. This very well could have been the problem the whole time. Hopefully it is. Either way, can someone point me in the right direction to finding an article to read on rebuilding/cleaning that holley?

And CDMinter59, thanks for the timing lecture, but where do those 8* and 34-36* come from. Aren't things a bit specific to each engine? And does anybody have any tips to help me hear any detonation I might have while timing over my loud exhaust? Or for that matter, hearing detonation at all? I can't say that I have ever heard it before. Thanks all. Waiting to hear from ya!
08-27-2012 10:22 PM
cdminter59
setting the timing

To set the timing you have to get the #1 cylinder on top dead center. #1 is the first cylinder in front of the engine on the driver side. Remove the spark plug from #1 cylinder. You will need a helper. Have the helper bump the engine over (while you have a finger against the spark plug hole). When you feel air pushing on your finger stop. Find the timing marker on the front of the timing chain cover. Clean the scale off so you can read it. You can mark the line on the balancer whiteout or chalk. Turn the balancer nut with a socket and breaker bar until line is on (0) on the scale. Ok now pop the cap to see which cylinder the rotor is pointing at on the cap. Trace the spark plug wire from the tower on the cap the rotor is pointing at to the spark plug end. Should be #1. Now is when you need a Timing Light with an advance dial. Summit Racing SUM-G1059 - Summit Racing® Timing Lights - Overview - SummitRacing.com. Disconnect the vacuum hose from distributor and plug the end of hose. Start the engine point timing light with advance knob on 0 at the scale. Turn distributor counterclockwise to advance timing to 8*. Lock down the distributor by tighten clamp until it will not turn. This is initial timing. Now to check mechanical advance. Set the knob to 36* on back of timing light. With the engine running have the helper rev the engine to about 3000 rpm while you are watching the scale. The line will align to 0 if the mech advance is set right. This is total advance .If not write down the number that it's pointing to. Now turn dial on the timing gun until the balancer lines up to 0. If its on 34 it's ok. Now what this means is you have 8* initial and 26* mechanical advance. If less than 34* total you have advance the initial some more until your total is 34-36*. Reconnect the vacuum hose to the distributor. Finished!
08-27-2012 06:44 PM
osweezea
Quote:
Originally Posted by DoubleVision View Post
First thing I suspect is the mechanical timing advance is sticking open. Don't matter what springs or weights are in it either. After a while if they get gummed up, and they all do, they will stick open and cause all kinds of headaches. What carb are you using? Because of how it's acting I don't think you have a vacuum leak, but it is something to check. If the carb is a 4 barrel the secondaries could be slightly sticking open which also happens at times as well. I used to have a Demon carb that had a bad habit of the secondaries sticking slightly open and I had to sand the burrs out of the base plate to stop it. See if you can get it to idle high again then check the secondary linkage to see if it's open any.
Thanks for these thoughts. As far as the mech advance sticking, how can I check this? If I turn the rotor all the way to the stop bushing, it will snap back easily. Is there another test for it?

As far as carb, I can't recall, but I will check on it tomorrow after work.

Thanks again. I'll keep this updated until I can figure it out.
08-27-2012 06:38 PM
osweezea
Quote:
Originally Posted by cdminter59 View Post
The first question I have for you is did you buy this JEEP with the motor already in it? Look on the base of the MSD distributor and find the Model #. Should be MSD 8516. Next pull the cap and remove the two screws for the rotor removal. Check the weights for rust and corrosion. Clean and put some dielectric grease on them, springs too. See weights: MSD Ignition 8628 - MSD Distributor Replacement Parts - Overview - SummitRacing.com. Check magnetic pickup for rust and corrosion, clean if necessary. If cap and rotor any white scale on posts replace with MSD Ignition 8014 - MSD Extra Duty Distributor Caps - Overview - SummitRacing.com MSD Ignition 8467 - MSD Distributor Rotors - Overview - SummitRacing.com Tighten the distributor hold down bolt until you can not turn the distributor. If you don't have a timing light borrow one to set the timing not by sound.
Yes I bought with motor in it and running, w/ approximately 2000 miles on it.
I would say it now has about 2500 off the top of my head.
Distributor Model number is 8519.
Weights seemed fine, but I will double check them
Cap and rotor will be getting replaced due to white scale
And as far as timing goes, I have never done it before but want to. I am just overwhelmed as to where to start. One concern that I have is not being able to hear any pinging when setting the initial(or total timing, I forget where that pinging comes in) because my exhaust is so loud. Anyone have any suggestions to hearing it with a loud exhaust? And any links to any really good write ups for a novice?

Do any of these symptoms sound like it could be bad dist/cam gears?

Thanks for the input.
08-26-2012 08:16 PM
DoubleVision First thing I suspect is the mechanical timing advance is sticking open. Don't matter what springs or weights are in it either. After a while if they get gummed up, and they all do, they will stick open and cause all kinds of headaches. What carb are you using? Because of how it's acting I don't think you have a vacuum leak, but it is something to check. If the carb is a 4 barrel the secondaries could be slightly sticking open which also happens at times as well. I used to have a Demon carb that had a bad habit of the secondaries sticking slightly open and I had to sand the burrs out of the base plate to stop it. See if you can get it to idle high again then check the secondary linkage to see if it's open any.
08-26-2012 08:03 PM
cdminter59
Idle speed changes

The first question I have for you is did you buy this JEEP with the motor already in it? Look on the base of the MSD distributor and find the Model #. Should be MSD 8516. Next pull the cap and remove the two screws for the rotor removal. Check the weights for rust and corrosion. Clean and put some dielectric grease on them, springs too. See weights: MSD Ignition 8628 - MSD Distributor Replacement Parts - Overview - SummitRacing.com. Check magnetic pickup for rust and corrosion, clean if necessary. If cap and rotor any white scale on posts replace with MSD Ignition 8014 - MSD Extra Duty Distributor Caps - Overview - SummitRacing.com MSD Ignition 8467 - MSD Distributor Rotors - Overview - SummitRacing.com Tighten the distributor hold down bolt until you can not turn the distributor. If you don't have a timing light borrow one to set the timing not by sound.
08-26-2012 06:36 PM
osweezea
Quote:
Originally Posted by 41 kustom View Post
Is your throttle sticking?
I don't think so. How could I tell?
08-26-2012 06:34 PM
osweezea
Quote:
Originally Posted by RWENUTS View Post
Sounds to me like the distributor weights are hanging up.
You got a light set of advance springs in it?
Well, I don't think so. It is an MSD with a light blue and heavy silver set of springs. This is the second to slowest combination of springs in the kit.
08-26-2012 05:22 PM
41 kustom
Carb

Is your throttle sticking?
08-26-2012 04:52 PM
RWENUTS Sounds to me like the distributor weights are hanging up.
You got a light set of advance springs in it?
08-26-2012 03:40 PM
osweezea
Idle speed changes

Well, I don't own any show cars or hot rods, but I consider my 79 Jeep CJ5 with a healthy AMC 360 to be my hot rod, and I am hoping to find some help here with my idle issues. So....we use this Jeep as a nice day cruiser and an offroad vehicle. The problem is when the jeep is ran moderately hard, the engine will not "idle down" or return to idle. The first time this happened, we were out driving over the sand dunes here in Michigan, running pretty hard in two wheel drive. We didn't quite get up and over the top of the dune, so I pressed the clutch in and found reverse to make our way back down. Once down to the bottom, the motor only idled down to @ 1500 rpm instead of the previous 900-1000 rpm. I took notice and made the hill again, and the issue somehow resolved itself. The next time this happened, it was the exact same situation, but on a different hill. And instead of the 1500, it only came back down to 2000 rpm. On this second occurence it was on the last of the dunes and we headed back to camp, and there was no change in idle speed. After a few hours of sitting at camp, fired it up and no change. A few more hours gone by, still no change.

So, at this point we decide to play with the timing a bit, and got it to idle down, but before we changed the timing, it was very easy to turn the distributor without loosening the hold down clamp, but the bolt was still tight.

Once home, I played with the timing again, got it where I thought I wanted it. TIGHTENED the bolt, free revved the engine, idled down to 1500. So, thinking we could have somehow bent the hold down, tried to bend it back and reset the timing. All seemed well. Next day went to a local cruise in town and things were good for say 45 min of running, then idle jumps up to 1200. Again reset idle timing, and all seemed well. Drive it nice and easy for a few days, then today during a moderate acceleration, idle jumps back to @1500 rpm.

So where do I go from here? It is an MSD dist.

My thoughts are:

While I am playing around with it all, I noticed some white powdery corrosion on the rotor and pickups under the cap, so get new rotor/cap.

Then:

- Try a new hold down clamp?
- Possible worn dist gear?
- shim between the hold down clamp and dist base?

I did not build this motor, and I am only beginning my quest here on motors, so any helpful thoughts/advice/suggestions, I will be grateful. Thanks for your time.

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