............U say this problem began with the FBO dist.........then take it out, put in old 1 and b happy......some motors can only tolerate so much timing does it miss at 10*...kim......
distributer reluctor air-gap check?
- Thread starter pjc360
- Start date
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BillGrissom
Well-Known Member
Try spraying starter fluid in the air cleaner when it is missing. If it smooths out, the problem is likely fuel related. Of course it could fire on ether better if a really weak spark, but I have run engines on starter fluid alone for short times.
A long shot is to verify rotor phasing. For this, you need a spare distributor cap, drill a large hole next to a tower and shine the timing light in (clamped around that spark wire) and see where the rotor is. It shouldn't move from rpm, but should vary +/-3 deg (cam degrees) with vacuum. If well off the tower or moves away with vacuum, that could cause mis-fire to the wrong tower.
If you give up with that distributor, you can get a "ready to run" distributor w/ HEI module for $45 on ebay that appears to have a better pickup design. Lose the ballast and old-fashioned coil.
A long shot is to verify rotor phasing. For this, you need a spare distributor cap, drill a large hole next to a tower and shine the timing light in (clamped around that spark wire) and see where the rotor is. It shouldn't move from rpm, but should vary +/-3 deg (cam degrees) with vacuum. If well off the tower or moves away with vacuum, that could cause mis-fire to the wrong tower.
If you give up with that distributor, you can get a "ready to run" distributor w/ HEI module for $45 on ebay that appears to have a better pickup design. Lose the ballast and old-fashioned coil.
You beat me to it. Don't assume because it is new that it wasn't marked wrong when made. From what you described I think it's in the timing.
Well i know the engine was on top dead center when i installed the fbo distributer because i took the number 1 spark plug out and bumped the engine over untill i felt compression against my finger. And when i shine my dial back timing light on my balancer everything seems to be matching up.... when i set my initial timing at 14 degrees then check my total timing it is at 32 degrees wich is correct because there is 18 degrees of mechanical advance inside the distributer. And if i move my initial timing up to 16 degrees then that makes my total timing land at 34 degrees. And all my timing is in by 3000 rpm wich is where don set it to be all in at.
I dont have another distributer to run it at the moment, well i do but the pick up assembly is screwed up and the pick up coil is old and it needs a new vaccum advance mechanism. I plan on sending my back up distributer wich is a mopar performance distributer as well with the mallory guts in it to don to have him put some new parts in it and curve and phase it for me. Just havent got around to doing it, i have my old mopar distributer with the mallory guts boxed up and its ready to be sent to him... i just need to come up with the money.
so how would i determine if my balancer is reading 100 percent correct? do i need timing tape? or can i get by doing it with just my dial back light? i dont have a piston stop... Is there anything i cn mke or jerry rig to use as one? like a coat hanger ect ect? I'm willing to make absolute sur my balancer is reading correctly. Just need to know what i need to do, and i'll give it a shot.
Two of us have told you. PISTON STOP Frankly I get tired of typing answers nobody reads.
THIS is a piston stop, you can buy or make them:
Read this
http://www.forabodiesonly.com/mopar/showthread.php?t=140556
i read what you wrote 67dart273, i just dont have a piston stop or have access to a store at the moment, thats why i was asking if its possible i can use something else as a piston stop? like a coat hanger? i have heard of people using coat hangers as piston stops before.
OK. You can MAKE one. Take a spark plug, and carefully saw all the way around the crimp. Cut off the ground, and use a punch or junk bolt to drive the guts out of the shell.
Then tap the shell for a 3/8 bolt. If you don't have a tap, drill/ ream the hole a little so you can slip a bolt in there and tack weld it. Leave plenty so you can trim it to length. You are not trying to stop the piston at TDC, but rather "down in the hole" some distance. Exact distance is not important. IMPORTANT thing is that the stem is a reasonable length and RIGID so it won't move.
Here's one I built over 30 years ago!!! The bolt as measured from the gasket surface is about 2 3/16, not critical.
Be sure to round the edges of the bolt off a little, so you don't put "nicks" in the piston dome
Then tap the shell for a 3/8 bolt. If you don't have a tap, drill/ ream the hole a little so you can slip a bolt in there and tack weld it. Leave plenty so you can trim it to length. You are not trying to stop the piston at TDC, but rather "down in the hole" some distance. Exact distance is not important. IMPORTANT thing is that the stem is a reasonable length and RIGID so it won't move.
Here's one I built over 30 years ago!!! The bolt as measured from the gasket surface is about 2 3/16, not critical.
Be sure to round the edges of the bolt off a little, so you don't put "nicks" in the piston dome
and i dont have to remove my distributer to do this correct? i rotate the engine counter clockwise untill it hits the piston stop, then i mark where that is on my balancer. then i rotate the engine clockwise untill it hits the piston stop and mark where once again on the balancer. and between those 2 marks is where true dop dead center of the number 1 piston will be correct? I still dont see why i couldnt use a coat hanger and just watch untill the coat hanger stops rising then mark on the balancer and do it thatway? i guess a piston stop is more accuarate but a coat hanger could work if your in a hurry and dont have the time to make a or get a piston stop.
In horseshoes, using a coat hanger is like a leaner, not quite a ringer. But yes it will get you close, but not perfect.
i tried using the coat hanger method and ended up getting frustrated and saying screw it. I will try and get a piston stop tommarrow. I am pretty sure this balancer is reading correctly tho, because there is only one line thru the balancer and it lines right up with the zero when i have my dial back timing light sitting at 14 degrees.
I really think its reading accuaratly. But who really knows untill i prove it is, i can find a piston stop tommarrow. just need to find one that will fit where the 5/8th spark plugs fit correct? I noticed it was thudding out the exhaust at all today. Went the whole day without doing it once, but sometimes it just up and starts doing it out of no where. My main culprit is the ecu box untill something proves me wrong with that. Just wish i had the money to buy a crae cd hi-6 ignition and thorw this ballast and wells box away.
I don't know about the magnums. You don't care how long it is as long as it is rigid, and stops the piston "some distance" down. It is important to remember that acuracy gets to be LESS closer to the stop, because as the crank comes "up and over" the piston slows down, giving you less "rate of change."
I would try about 2 1/2 and see how it works. You don't want it to hit valves or the other side of the bore.
I would try about 2 1/2 and see how it works. You don't want it to hit valves or the other side of the bore.
well i got the porcalien knocked out of one of my spark plugs i had laying around, that was a job and a half, now i need to get a 3/8 bolt and see if one of the mechanics around town has a tap and die, if not i guess i will just weld a bolt in there and make the length 2 1/2 inches long.
ok well the piston stop results are inn, I made a piston stop to check top dead center on the number 1 cylinder and i have come to find out that my balancer is reading awfully darn close but it might be off by about 1/4 to a 1/2 inch. from my first mark to the original balancer mark is 3 inches exactly, then from my second mark to the original balancer mark it is 2 3/4 inches exactly.
So is it safe to say my balancer is reading correctly? Is that close enough to say yes the balancer is reading the timing correctly?
My piston stop is about 2 1/4 inch long.
So now the fun part... Figuring out why this engine is missing at an idle occsionally, worse with the vaccum advance on manifold vaccum but it sometimes does it with the vaccum advance on ported vaccum and with the initial timing sitting at 14 degrees and total timing sitting at 32 degrees.
So is it safe to say my balancer is reading correctly? Is that close enough to say yes the balancer is reading the timing correctly?
My piston stop is about 2 1/4 inch long.
So now the fun part... Figuring out why this engine is missing at an idle occsionally, worse with the vaccum advance on manifold vaccum but it sometimes does it with the vaccum advance on ported vaccum and with the initial timing sitting at 14 degrees and total timing sitting at 32 degrees.
so i was wrong from line to line it was 6 inches and the original timing mark on the damper is in the middle, so my balancer is reading correctly.
When i was taking out all the spark plugs i noticed the number 3 cylinder spark plug wwas pitch black and looked as if it wasnt firing. So i threw in the brand new autolite 3923's that i bought.
Put the autolites back in it, fired it up and let it warm up, and just for the hell of it i switched the ported vaccum over to the manifold vaccum and sure enough it started missing out the exhaust thudding and puffing and no matter how rich i went on the idle air screws on the carburetor it didnt change a thing, so then i put the vaccum advance back on ported and it was still thudding out the exhaust and missing, so i turned up the idle and it got worse as i increased the idle.
I got so fed up with it that i just shut it off and left. This issue has been driving me insane for the last 3 or 4 months. I cant believe i have not figured this out yet.
There has to be a way to track this problem down and find a solution to it.
It's not the spark plugs they are brand new autolite 3923's, the coil is a crane cams lx91 coil and it is working. Distributer doesnt even have 1000 miles on it bought from don at fbo systems. Ever since he suggested running vaccum advance off of manifold vaccum wih his distributer is when i noticed this entire issue.
What could be wrong inside the distributer to cause this? I dont think its too much timing i dont think timing has anything to do with this issue, i think it is ether distributer or ignition module related. Basically have limited it down to the distributer or to the ignition module its self. What else it could be?
Balancer is correct, so i know the timing is right, and it dont matter if the vaccum advance is on ported or manifold vaccum it still misses its just a little moe noticeable with the vaccum advance on manifold vaccum.
distributer cap and rotor are brand new, all my ignition wiring is brand new. This is such a strange issue i have never seen anything like it, thats for dam sure.
When i was taking out all the spark plugs i noticed the number 3 cylinder spark plug wwas pitch black and looked as if it wasnt firing. So i threw in the brand new autolite 3923's that i bought.
Put the autolites back in it, fired it up and let it warm up, and just for the hell of it i switched the ported vaccum over to the manifold vaccum and sure enough it started missing out the exhaust thudding and puffing and no matter how rich i went on the idle air screws on the carburetor it didnt change a thing, so then i put the vaccum advance back on ported and it was still thudding out the exhaust and missing, so i turned up the idle and it got worse as i increased the idle.
I got so fed up with it that i just shut it off and left. This issue has been driving me insane for the last 3 or 4 months. I cant believe i have not figured this out yet.
There has to be a way to track this problem down and find a solution to it.
It's not the spark plugs they are brand new autolite 3923's, the coil is a crane cams lx91 coil and it is working. Distributer doesnt even have 1000 miles on it bought from don at fbo systems. Ever since he suggested running vaccum advance off of manifold vaccum wih his distributer is when i noticed this entire issue.
What could be wrong inside the distributer to cause this? I dont think its too much timing i dont think timing has anything to do with this issue, i think it is ether distributer or ignition module related. Basically have limited it down to the distributer or to the ignition module its self. What else it could be?
Balancer is correct, so i know the timing is right, and it dont matter if the vaccum advance is on ported or manifold vaccum it still misses its just a little moe noticeable with the vaccum advance on manifold vaccum.
distributer cap and rotor are brand new, all my ignition wiring is brand new. This is such a strange issue i have never seen anything like it, thats for dam sure.
what could be going on in the distributer its self to cause an issue like the one i am having. Pick up coil not reading good? shaft floating? I dont know, i guess i will call don at fbo systems and send my distributer that i purchased from him back to him and tell him to fix whatever it is. cause i am out of guesses here.
What does the timing do when you hook/ unhook the vacuum?
You can EASILY mark the balancer for advance. But you have to be CAREFUL. After your description of your piston stop escapade, I sort of wonder.
If you take a small flexible tape, and measure CAREFULLY all the way around the balancer, then figure out mathematically how many "degrees per inch" you have, that is, 360 * in a circle
Then you can figure out how many inches would be 40*. Mark that off. Then take dividers, and divide that in half, for 20, then half again, for 10. With the dividers still set on 10, add another 10 on the end of 40, so you have 50.
Now you'll have marks every 10, out to 50, and you can easily see what the advance mechanism is doing.
Once you learn how to use these, you can easily refer to the timing tab 5* mark, and get these 10* marks down to 5 or even 2 1/2.
You can EASILY mark the balancer for advance. But you have to be CAREFUL. After your description of your piston stop escapade, I sort of wonder.
If you take a small flexible tape, and measure CAREFULLY all the way around the balancer, then figure out mathematically how many "degrees per inch" you have, that is, 360 * in a circle
Then you can figure out how many inches would be 40*. Mark that off. Then take dividers, and divide that in half, for 20, then half again, for 10. With the dividers still set on 10, add another 10 on the end of 40, so you have 50.
Now you'll have marks every 10, out to 50, and you can easily see what the advance mechanism is doing.
Once you learn how to use these, you can easily refer to the timing tab 5* mark, and get these 10* marks down to 5 or even 2 1/2.
So kitcarlson, can you describe to me in better detail the timing light check to check the othe spark plugs? I am really starting to think this issue is in the distributer. even tho its a brand new distributer that i paid 200 bucks for from don at FBO systems, he curved and phased it.
But i cant think of anything else to blame this on, my balancer is reading right, plugs are new, wires are new and working. Coil is new and working.
Ecu is fairly new and is grounded. What else can be causing this? its not my carburetor because when i pull the hose of of manifold vaccum it creates a vaccum leak, so my carburetor should not be causing the problem. Every once in awhile i find dead plugs that have not been firing. so this all points to the distributer, even tho its brand new less then 500 miles on the dam thing.
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