At this point I think I would compression test it. Inspect the plugs while you have them out. Double check firing order.
Two Dead Cylinders
- Thread starter mchandford
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Start with the basics first. Look at the attached diagram and make sure your spark plug wires are hooked up to the distributor as indicated.
If you're still having trouble, post back here for some info about doing the compression check.
Good luck, and keep us in the loop!
If you're still having trouble, post back here for some info about doing the compression check.
Good luck, and keep us in the loop!
mchandford
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Thanks Marks73 and everyone else trying to help out. I have said it before and I will say it again. i am no mechanic. I do know how to check the plug wires, I was just writing that on the list of things to check. Thanks for the diagram as well, saves me from finding it. I have one more week before my transfer and I will be back at the car for a day. Probably won't have a lot of time to play with it, but i think i can knock a couple items off the list. Military moves are time consuming sometimes. I will keep posting updates when I get them. Thanks everyone.
+ 1 - See earlier post concerning respect and dignity.
keep in mind YOUR #1 might not be in that exact location.
mchandford
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Ya. Thats what I'm saying, maybe something got messed up while I have been messing with it, or at the shop, or before I got it. I just have never looked specifically at that, so it's something to put on the list.
As far as messing with the carb. Adjusting it and leaving it is what you do when adjusting it worked. But when the air screws do nothing to your idle, or how the car runs, something is up. Not saying it is in the carb, but it is one place to look.
Thanks again guys. I am getting antsy to get to my new house, my new garage, and my car.
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Thanks again to you, mchandford, for your service. Moving from duty station to duty station sucks (I've been there) and having to worry about a vehicle can make it worse. We'll help with getting your 'stang running, so don't worry about that. Just make sure the PCS orders are in shape, and that the rest of your move goes smoothly. Let us know when you get to give the 'Stang a pat on the back.
mchandford
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Thank you. I have had orders in hand since August. I just got my partial payment for moving expenses today. Doing our last packing this week, getting the moving truck Saturday, load all day Saturday and what ever's left Sunday morning, then driving 350 miles with a 26' Penske all day Sunday. Unload Sunday night and Monday morning, then drive back to this side of Washington. Do our move out inspection on the rental and drive back again Tuesday. Then I can settle down for a couple days and check on these dead cylinders.Thanks again to you, mchandford, for your service. Moving from duty station to duty station sucks (I've been there) and having to worry about a vehicle can make it worse. We'll help with getting your 'stang running, so don't worry about that. Just make sure the PCS orders are in shape, and that the rest of your move goes smoothly. Let us know when you get to give the 'Stang a pat on the back.
72HCODE
"My World is Fire and Blood"
if the idle air bleed screws do nothing, that means the butterflies are open too far exposing too much of the transition slot.
usually the secondaries are not set correctly, somebody either opened them too far or, the carb is too big for the engine causing low vacuum and not enough pull at idle which makes you open up the primaries and secondaries thinking it isn't getting enough air.
with the bleed screws set at 1.5 turns the car should be setup to idle, you then turn at least one screw down to close the bleed, if the engine doesn't lower rpm or stall out then the primaries or secondaries are open too much. you have to balance the opening of the primaries and secondary butterflies which is a PAIN in the but since the carb has to usually come off the intake manifold because the secondaries adjustment screw is usually accessed from underneath the carb base. (the screw is also very easy to strip out)
you have to sit there and adjust the butterflies so the idle slot is exposed by not the transition slot.. i can't remember the specs if you use a gauge like .20" or something.
if a carb is rebuilt the rebuilder usually screws this up and leaves the secondaries open incorrectly. so what happens is with the secondaries open too far, you then compensate trying to close the primaries. and then you find out the screws do nothing because when they are closed down,,, too much air and fuel is going through the secondaries on the carb.
if you take the air cleaner off, and open the choke, look down the barrels with a flashlight and see the position of the butterflies, this is if you have a 4 barrel which alot of people put on the motor.
now if a carb is too big for a motor then the CFM will always flow too much fuel and air at idle. if a carb is too small that forces you to open up the butterflies again and cause a similar issue but not because the carb isn't flowing enough air and fuel at idle.
it all plays off each other also. for example Spiral core ignition wires which 90% of the aftermarket sells as a HP upgrade can cause misfires and timing problems that force you to think you have a carb issue. that makes you start to fart around with the carb all the time and you never make progress.
everything gets intertwined so that is why you want to sort of start over.... if this was me i would look over the engine and i would most likely pull the plugs and look at them first, then if i find aftermarket ignition wires, in the trash they go, and if somebody put a HEI Distributor cap i would most likely ditch that and go back to a standard oem type ford distributor cap and rotor and check what electronic or points system the car had on it. for testing i might go back to points just to rule out an issue with the resistance wire, or even run a temp bypass to rule out ignition problems sort of give the car a tune up just to remove questionable parts. while changing the plugs i would then do a compression test, really easy with a remote starter connected to the car. i would test the cyclinders and if everything was with in good limits rule that out as valve issue.
with mechanical issues checked, and electrical issues checked off with a tune up and replaced questionable parts, then i would attempt to start the car and check init timing with a light and make sure if the car started that all the plugs were firing with a set pattern.... if there was an electronics ignition issue what i have seen happen is one or more plugs fire with a random sequence instead of a normal heartbeat, I've had the magnetic ring on a petronix II go bad and one plug would basically fire randomly and i would see it with the vac gauge and the timing light not firing correctly.
once the thing is going then i would hit the carb if i find the bleed screws are doing nothing i would check the CFM of the carb, and do some research on it. pull it off and inspect the butterflies and how open or closed they are.
When i got my Turn key motor back from my builder(what a joke that was btw) he had set the holley carb completely wrong because he was compensating for an ignition problem on a bran new engine that he had just put together(yes i would of liked to strangle him)
I had to take all the Aftermarket BS he put on the engine off, go back to OEM which is always better and restart the tune, then it took a while to really fine tune it and compensate for the engine builders other mistakes he made internally on the engine(never use open chamber late model V4 heads on a early V2 engine, closed chamber always)
basically even a seasoned mechanic isn't going to know everything especially on your car. mechanics are good at general knowledge not specific knowledge.
when you have the car and are looking under the hood that is when you can get started figuring out what is wrong and were to start.
if the car does have mechanical damage then at least you will know the source of the problems.
btw 10 years ago i started with ZERO car knowledge,, i got a trial by fire and made it out with some skin left,,, not much.
i wish i could go back to how my car was originally knowing what i know now and play detective back then before a bunch of experts i hired Screwed the whole thing up before i figured out what was going on and started to tackle the problems myself.
should also point out, diagnostics via internet is VERY hard to do, because one issue can be caused by 100 different things. you have to start to get into it and have a feel of where to start based on your skill level and the tools you have in the garage. 10 years ago i was scared to even touch my engine. the first time i went to check and change the thermostat i snapped a bolt off in the block with less then 5 foot pounds of torque on the bolt(turned out to be a defective bolt that was not hardened properly) that ran me away from my engine for about a year the thing sat in the garage, then a buddy of mine helped me cut the bolt out since all the easy outs failed to get it out of the block. we sat on top of the engine block taking turns with a carbide cutter and dremel tool for 8 hours cutting all the bad bolt out and then using a tap and saving the original threads otherwise i would of needed to helicoil my block.
Its funny looking back all those years ago at how a minor issue scared me to death. i also leaned the aftermarket for cars is basically snake oil as well,,, in this case my original iron thermostat neck was rusted out and leaking and i bought a ford racing chrome neck which came with defective bolts that were as soft as butter,,, my buddy took the second bolt that came in the kit and he bent it bare handed.
after all that we installed the new neck and new thermostat with correct bolts. the thing leaked so bad it wasn't even funny the o-ring sealed nothing and i had to buy a OEM cleveland thermostat neck and just used the gasket and sealet as original,,, what a shock it never leaked again and was fine.
usually the secondaries are not set correctly, somebody either opened them too far or, the carb is too big for the engine causing low vacuum and not enough pull at idle which makes you open up the primaries and secondaries thinking it isn't getting enough air.
with the bleed screws set at 1.5 turns the car should be setup to idle, you then turn at least one screw down to close the bleed, if the engine doesn't lower rpm or stall out then the primaries or secondaries are open too much. you have to balance the opening of the primaries and secondary butterflies which is a PAIN in the but since the carb has to usually come off the intake manifold because the secondaries adjustment screw is usually accessed from underneath the carb base. (the screw is also very easy to strip out)
you have to sit there and adjust the butterflies so the idle slot is exposed by not the transition slot.. i can't remember the specs if you use a gauge like .20" or something.
if a carb is rebuilt the rebuilder usually screws this up and leaves the secondaries open incorrectly. so what happens is with the secondaries open too far, you then compensate trying to close the primaries. and then you find out the screws do nothing because when they are closed down,,, too much air and fuel is going through the secondaries on the carb.
if you take the air cleaner off, and open the choke, look down the barrels with a flashlight and see the position of the butterflies, this is if you have a 4 barrel which alot of people put on the motor.
now if a carb is too big for a motor then the CFM will always flow too much fuel and air at idle. if a carb is too small that forces you to open up the butterflies again and cause a similar issue but not because the carb isn't flowing enough air and fuel at idle.
it all plays off each other also. for example Spiral core ignition wires which 90% of the aftermarket sells as a HP upgrade can cause misfires and timing problems that force you to think you have a carb issue. that makes you start to fart around with the carb all the time and you never make progress.
everything gets intertwined so that is why you want to sort of start over.... if this was me i would look over the engine and i would most likely pull the plugs and look at them first, then if i find aftermarket ignition wires, in the trash they go, and if somebody put a HEI Distributor cap i would most likely ditch that and go back to a standard oem type ford distributor cap and rotor and check what electronic or points system the car had on it. for testing i might go back to points just to rule out an issue with the resistance wire, or even run a temp bypass to rule out ignition problems sort of give the car a tune up just to remove questionable parts. while changing the plugs i would then do a compression test, really easy with a remote starter connected to the car. i would test the cyclinders and if everything was with in good limits rule that out as valve issue.
with mechanical issues checked, and electrical issues checked off with a tune up and replaced questionable parts, then i would attempt to start the car and check init timing with a light and make sure if the car started that all the plugs were firing with a set pattern.... if there was an electronics ignition issue what i have seen happen is one or more plugs fire with a random sequence instead of a normal heartbeat, I've had the magnetic ring on a petronix II go bad and one plug would basically fire randomly and i would see it with the vac gauge and the timing light not firing correctly.
once the thing is going then i would hit the carb if i find the bleed screws are doing nothing i would check the CFM of the carb, and do some research on it. pull it off and inspect the butterflies and how open or closed they are.
When i got my Turn key motor back from my builder(what a joke that was btw) he had set the holley carb completely wrong because he was compensating for an ignition problem on a bran new engine that he had just put together(yes i would of liked to strangle him)
I had to take all the Aftermarket BS he put on the engine off, go back to OEM which is always better and restart the tune, then it took a while to really fine tune it and compensate for the engine builders other mistakes he made internally on the engine(never use open chamber late model V4 heads on a early V2 engine, closed chamber always)
basically even a seasoned mechanic isn't going to know everything especially on your car. mechanics are good at general knowledge not specific knowledge.
when you have the car and are looking under the hood that is when you can get started figuring out what is wrong and were to start.
if the car does have mechanical damage then at least you will know the source of the problems.
btw 10 years ago i started with ZERO car knowledge,, i got a trial by fire and made it out with some skin left,,, not much.
i wish i could go back to how my car was originally knowing what i know now and play detective back then before a bunch of experts i hired Screwed the whole thing up before i figured out what was going on and started to tackle the problems myself.
should also point out, diagnostics via internet is VERY hard to do, because one issue can be caused by 100 different things. you have to start to get into it and have a feel of where to start based on your skill level and the tools you have in the garage. 10 years ago i was scared to even touch my engine. the first time i went to check and change the thermostat i snapped a bolt off in the block with less then 5 foot pounds of torque on the bolt(turned out to be a defective bolt that was not hardened properly) that ran me away from my engine for about a year the thing sat in the garage, then a buddy of mine helped me cut the bolt out since all the easy outs failed to get it out of the block. we sat on top of the engine block taking turns with a carbide cutter and dremel tool for 8 hours cutting all the bad bolt out and then using a tap and saving the original threads otherwise i would of needed to helicoil my block.
Its funny looking back all those years ago at how a minor issue scared me to death. i also leaned the aftermarket for cars is basically snake oil as well,,, in this case my original iron thermostat neck was rusted out and leaking and i bought a ford racing chrome neck which came with defective bolts that were as soft as butter,,, my buddy took the second bolt that came in the kit and he bent it bare handed.
after all that we installed the new neck and new thermostat with correct bolts. the thing leaked so bad it wasn't even funny the o-ring sealed nothing and i had to buy a OEM cleveland thermostat neck and just used the gasket and sealet as original,,, what a shock it never leaked again and was fine.
I had a couple water necks leak, which can make the dizzy get stuck after a while. Canton makes very good ones.
72HCODE
"My World is Fire and Blood"
you know when a racing part is covered in chrome you will have a bad day. The chrome coating on those parts is usually poor, and is porous, the plating is usually such low quality that the chrome separates from the base metal that basically allows the seal to be circumvented thus something like that will leak even covered in sealant. as a newbie you see "FORD RACING" so it must be good and you buy it thinking it is an upgrade. Same thing with the ford racing chrome oil pans with the addition of the pan being so flimsy just tightening the bolts warps the lip of the flange and it will never seal and weep fluid for ever. After years of trying to find a great extended capacity C6 pan that was not covered in chrome and was thick enough. I finally found a company that made steel pans for Offroaders that ran using the C6. it was the best money i ever spent the pan will out last the planet hahahaha has a built in baffle and plug, once installed i never had a problem again. if i sell the car i'm taking that pan with me. sadly the company that fabricated them is no longer around.
the canton necks are very nice machined from aluminum. if i did racing it would be on the list of things to buy for weight and function.
the canton necks are very nice machined from aluminum. if i did racing it would be on the list of things to buy for weight and function.
mchandford
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Well I replaced the spark plug wires. I definitely needed to. Yesterday after starting the car and grumbling that it still sounded like crap I was pushing in the distributor ends of the spark plug wires to see if one was loose and the dang thing shocked me! Felt awesome. So ordered OEM plugs. got them today put them all in, checking the firing order as i went. Everything went together well, fit well (except the coil to distributor lead, it was too short). But when I started it up it sounded basically the same. Maybe a little better. So i pulled the driver's side plugs one at a time to see which ones were not firing. #7 and #8. HMMM...that cant be a coincidence. Got some WD40 and started spraying, again, to check for vacuum leaks. I found it!
[attachment=15134]
This is after I put a cap back on it. The old one must have come off during shipping. I put a slightly smaller cap on and had to really jam it on there. Sounds better already.
Went back to double check timing and air screws.
The screws definitely work now. 1 and 1/2 turns out exactly on both. Either direction on either screw and the car stumbles.
Timing is where I am confused at this point. i will start another post, but basically I HAD ported vacuum hooked up- timing at idle was 12, I put it back to 6. Sounded ok. With it at 10 sounds and runs much better.
I decided to try the manifold vacuum, as I was told that was the way to go. With initial timing still at 10 I hooked up the manifold vacuum to vac advance and got almost 32 deg at idle and 55 at about 3500 rpms.
That seems like way too much and the car was running like crap. So i out it back on ported vacuum and left it at 10deg initial. Which gave me about 32 total at 3500rpm. I think this works, but maybe i'm not really taking advantage of my vacuum advance.
Anyone have any thoughts on this? I think I will need to change the spring (others?) inside the distributor to make this work.
[attachment=15134]
This is after I put a cap back on it. The old one must have come off during shipping. I put a slightly smaller cap on and had to really jam it on there. Sounds better already.
Went back to double check timing and air screws.
The screws definitely work now. 1 and 1/2 turns out exactly on both. Either direction on either screw and the car stumbles.
Timing is where I am confused at this point. i will start another post, but basically I HAD ported vacuum hooked up- timing at idle was 12, I put it back to 6. Sounded ok. With it at 10 sounds and runs much better.
I decided to try the manifold vacuum, as I was told that was the way to go. With initial timing still at 10 I hooked up the manifold vacuum to vac advance and got almost 32 deg at idle and 55 at about 3500 rpms.
That seems like way too much and the car was running like crap. So i out it back on ported vacuum and left it at 10deg initial. Which gave me about 32 total at 3500rpm. I think this works, but maybe i'm not really taking advantage of my vacuum advance.
Anyone have any thoughts on this? I think I will need to change the spring (others?) inside the distributor to make this work.
So you say you found a vacuum leak? Imagine that.
http://www.fordmuscle.com/archives/2000/03/timing/
Discussion on manifold vs ported vacuum. http://www.bangshift.com/forum/showthread.php/33503-Ported-vs-manifold-vacuum-advance
http://www.fordmuscle.com/archives/2000/03/timing/
Discussion on manifold vs ported vacuum. http://www.bangshift.com/forum/showthread.php/33503-Ported-vs-manifold-vacuum-advance
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mchandford
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Thanks for the link. I had seen that one before but it was just what I was looking for today. Like I said in my post I guess that cap came off in shipping. Still freaked me out though. I will check out the insides of the distributor later today or tomorrow and see if I can find lighter springs for it.
Springs arent hard to find. And find vac port caps that fit. You can get an assortment pack for a couple bucks. You do not want to force on the wrong size. It may leak. It may split. You may cut it and jam rubber in the port. You might want to take it easy on the WD-40. I have never put that stuff on my engine.
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Holy crap, that's a great write-up. I bookmarked it. Thanks for that.
mchandford
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I got the cap on cleanly I just wanted to make sure I got a size that wouldn't come back off on its own. Actually now that I think about it I wonder if a backfire could have popped that off.
And i always wipe the WD40 off when I'm done spraying.
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