just rebuilt runs bad

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6tfo said:
Can't locate my old points distributor. Would a pointless distributor out of a 74, 318 work for testing until I get a points distributor (I'll have to order)?
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You should be able to use that distributor but you will still have to keep the MSD installed unless you have a factory ignition box and resistor laying around too.
It's worth a try.
 
Used the 74, 318 distributor (no points). It acted the same as the MSD distributor, runs nicely at 45 BTDC and poorly at 15-20 BTDC. Double checked everything.

I'm going to call Advance and order a new point distributor $40 plus $15 core. They'll have it in the am.
 
6tfo said:
Used the 74, 318 distributor (no points). It acted the same as the MSD distributor, runs nicely at 45 BTDC and poorly at 15-20 BTDC. Double checked everything.

I'm going to call Advance and order a new point distributor $40 plus $15 core. They'll have it in the am.
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Don't know if this was discused in an earlier reply, Seeing its acting the same with another dist. it could be the MSD box or a slipped balancer, If the points act'd the same "timing wise" i'd suspect the Balancer, Did you ever fined TDC to make sure the balancer lines up at 0 on the tab?

You say it runs nice at 45 BTDC, but runs poorly at 15-20*, I hope you mean at idle on that 15-20 & not max advance, because it will not run good there, have you tried 35-36* max from the 45*??
 
JoeDust451 said:
Don't know if this was discused in an earlier reply, Seeing its acting the same with another dist. it could be the MSD box or a slipped balancer, If the points act'd the same "timing wise" i'd suspect the Balancer, Did you ever fined TDC to make sure the balancer lines up at 0 on the tab?

You say it runs nice at 45 BTDC, but runs poorly at 15-20*, I hope you mean at idle on that 15-20 & not max advance, because it will not run good there, have you tried 35-36* max from the 45*??
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Thanks, I used a piston stop to verify TDC and the timing mark lined up perfectly to zero.

I'm getting the best idle and throttle response when initial timing is set for 45* BTDC. The more I retard the timing from 45* the worse the engine runs. The motor will stall out, even when increasing the idle speed, once I get around 10 BTDC or below.
 
...when initial is set for 45* and I increase RPM I can see mechanical advance kick in and it ends up exceeding 60*
 
Have you tried reversing the leads from the MSD box to the distributor? If the polarity to the distributor is wrong, it will require the advance you are talking about to run, but it will never run good reversed.
 
IQ52 said:
Have you tried reversing the leads from the MSD box to the distributor? If the polarity to the distributor is wrong, it will require the advance you are talking about to run, but it will never run good reversed.
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Thanks, I will double check, but is it possible to reverse the leads using the factory connectors off the MSD distributor and MSD box? Seems it would only connect one way.
 
IQ52 said:
Have you tried reversing the leads from the MSD box to the distributor? If the polarity to the distributor is wrong, it will require the advance you are talking about to run, but it will never run good reversed.
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I'm not familiar with the MSD stuff, but something along those lines makes sense. This is the reason I advocate getting rid of all the "hi tech" ignition and putting a basic points system in until it gets sorted out.

You post sounds like that you are basically saying "its a rotor phasing problem."

This can happen in many systems, especially with "non factory" wiring, whereby the trigger that makes the spark happen (reluctor/ trigger wheel) does not make the spark when the distributor rotor is aligned with the distributor cap plug tower contact.
 
you could have the lead reversed from the MP distributor to the msd...and you can have the orange and black wire reversed on the coil...
 
67Dart273 said:
I'm not familiar with the MSD stuff, but something along those lines makes sense. This is the reason I advocate getting rid of all the "hi tech" ignition and putting a basic points system in until it gets sorted out.

You post sounds like that you are basically saying "its a rotor phasing problem."

This can happen in many systems, especially with "non factory" wiring, whereby the trigger that makes the spark happen (reluctor/ trigger wheel) does not make the spark when the distributor rotor is aligned with the distributor cap plug tower contact.
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Thanks, I'm taking steps to go all the way back to a points system if I have to, starting with installing a points distributor tomorrow (if it comes in as promised). Unfortunately, I didn't keep any of the original ignition.
 
67Dart273 said:
You post sounds like that you are basically saying "its a rotor phasing problem."
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Yeah, pretty much. To check rotor phasing, I drilled a big hole in an extra distributor cap between the #1 post and the coil post just so I could point the timing light at the hole and see the rotor when the ignition fired.

With the wires reversed, the distributor tries to fire with the rotor between the cap posts even when you have everything correct physically. I once took a Mallory distributor apart and put the magnet in backwards. It had the same symptoms, in that, until you advanced it like crazy it would backfire through the carb. Reversed the wires to the distributor and it ran great. I took the distributor apart and put the magnet in correctly and switched the wires back.

With the symptoms the OP has, I would just set the advance I want on the damper, align the reluctor and pick up, reverse the wires and see what happens.
 
6tfo said:


Thanks, I will double check, but is it possible to reverse the leads using the factory connectors off the MSD distributor and MSD box? Seems it would only connect one way.
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I was leading to this, but i figured he went over the wiring, Now having the polarity off will do this, it'll jack the timing way up like your exsperiancing, you need to make sure the wiring is right at the coil too.
 
IQ52 said:
Yeah, pretty much. To check rotor phasing, I drilled a big hole in an extra distributor cap between the #1 post and the coil post just so I could point the timing light at the hole and see the rotor when the ignition fired.

With the wires reversed, the distributor tries to fire with the rotor between the cap posts even when you have everything correct physically. I once took a Mallory distributor apart and put the magnet in backwards. It had the same symptoms, in that, until you advanced it like crazy it would backfire through the carb. Reversed the wires to the distributor and it ran great. I took the distributor apart and put the magnet in correctly and switched the wires back.

With the symptoms the OP has, I would just set the advance I want on the damper, align the reluctor and pick up, reverse the wires and see what happens.
Click to expand...

Again, not familiar with MSD, on the OP's distributor, is it possible to get the reluctor/ star wheel in wrong?
 
67Dart273 said:
is it possible to get the reluctor/ star wheel in wrong?
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Not possible "unless" they jacked with it but i doubt it, Now that i'm thinking back, i had the same problem, it was a polarity issue, I'm thinking i had the dist. wires crossed, Now this was running an MSD box with a MP distributor, I couldn't time it for sh*t, had to clip the 2 wire plug to wire it up to the MSD, I accidently crossed the wires, The timing was way advanced before it would run right, freaked me out, Now in reality the timing was right when i got it running good, just didn't read right, Its very possible it was crossed on the coil too, its been awhile back so my memory is fuzzy, But i know it was a crossed wire & polarity issue.

The dist. you have is a Magnetic Pickup, here is the diagram, Its simple, just double check the wiring.

http://www.google.com/imgres?q=msd+...nw=217&start=117&ndsp=10&ved=1t:429,r:0,s:117

6tfo, When you install the point dist., don't hook it up through the MSD, Just run it by itself, hook the large brown factory wire from the fire wall to the + on the coil, then the black wire from the dist. hook to the - side of the coil, Now on this dist. definitly hook up the vacuum advance, timed port should be fine, direct port it'll bring the timing up a good 10-12 deg*, If your able to time it propperly, then its either in the MSD box or the polarity's off.
 
JoeDust451 said:
6tfo, When you install the point dist., don't hook it up through the MSD, Just run it by itself, hook the large brown factory wire from the fire wall to the + on the coil, then the black wire from the dist. hook to the - side of the coil, Now on this dist. definitly hook up the vacuum advance, timed port should be fine, direct port it'll bring the timing up a good 10-12 deg*, If your able to time it propperly, then its either in the MSD box or the polarity's off.
Click to expand...

Will do, not sure what "timed port/direct port" means but I'll do a little research.

You guys may be on to something. I verified the MSD wiring several times but I did find that silicone inside the (used) MSD Dist.. I'm wondering now if it wasn't holding something that was put in backwards or covering wiring that was crossed.

Also, when I hooked up the Mopar distributor, I had to use alligator clips to connect to the MSD. It was dark and I can't say for sure they weren't reversed.

Going now to get the points Dist. this morning.

Thanks!
 
6tfo said:
Will do, not sure what "timed port/direct port" means but I'll do a little research.

You guys may be on to something. I verified the MSD wiring several times but I did find that silicone inside the (used) MSD Dist.. I'm wondering now if it wasn't holding something that was put in backwards or covering wiring that was crossed.

Also, when I hooked up the Mopar distributor, I had to use alligator clips to connect to the MSD. It was dark and I can't say for sure they weren't reversed.

Going now to get the points Dist. this morning.

Thanks!
Click to expand...


Timed port is taken from above the throttle plate and has no vacuum at idle.
Direct port has full vacuum at idle. All initial timing should be set with the vacuum line disconnected from the vacuum advance.
Silicone is used in the MSD distributor to help secure the magnetic pickup from vibration, even from the factory.
When those pickups are replaced the magnet has to be installed the correct way and the gap to the reluctor has to be .025 to .030. If it's been replaced there is also a possibility that it was tightened too much and the magnet has cracked which will cause all kinds of false triggering.
 
6tfo said:
Will do, not sure what "timed port/direct port" means but I'll do a little research.

You guys may be on to something. I verified the MSD wiring several times but I did find that silicone inside the (used) MSD Dist.. I'm wondering now if it wasn't holding something that was put in backwards or covering wiring that was crossed.

Also, when I hooked up the Mopar distributor, I had to use alligator clips to connect to the MSD. It was dark and I can't say for sure they weren't reversed.

Going now to get the points Dist. this morning.

Thanks!
Click to expand...

Direct port vacuum is on the base plate of the carb in most cases, if its a holley carb, the timed port will be on the left hand side of the metering block, but like mentioned, have it disconnected while setting the timing.

Oh while i'm thinking about it, if by chance you ran a jumper wire & disconnected the ballast resitor, you'll need to hook it back up.
 
If I'm understanding correctly I just plug the vacuum port on the carb for port timing.

10-4 on the ballast resistor.

Thanks.
 
I just watched your video. It looks like you have the no 1 wire marked with the blue tape on the cap. However, I do not see the inductive clip from your timing light on the same wire. Is it on no 1 and I just can't make it out?
 
JoeDust451 said:
. definitly hook up the vacuum advance, .
Click to expand...

Sorry REALLY disagree with this. I say do NOT hook up the vacuum advance until you get things sorted out. Hell I don't run vacuum at all.

Stick that points rig in there, "power time" at high RPM to about 35* so that the advance is "in" then idle down and see what you have for intitial timing.

THEN LEAVE IT ALONE (the timing) until you check out other areas
 
GMachineDartGT said:
I just watched your video. It looks like you have the no 1 wire marked with the blue tape on the cap. However, I do not see the inductive clip from your timing light on the same wire. Is it on no 1 and I just can't make it out?
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Nice observation. I very confident the light pickup was on #1. Thanks.
 
kman521 said:
Silicone is used in the MSD distributor to help secure the magnetic pickup from vibration, even from the factory.
When those pickups are replaced the magnet has to be installed the correct way and the gap to the reluctor has to be .025 to .030. If it's been replaced there is also a possibility that it was tightened too much and the magnet has cracked which will cause all kinds of false triggering.
Click to expand...

Good to know. Thank you.
 
Didn't read all the posts but just saw the video and it sounds good. Did you ever check the harmonic balancer against another 340 and make sure the mark is in the right place?
 
Purple Haze said:
Didn't read all the posts but just saw the video and it sounds good. Did you ever check the harmonic balancer against another 340 and make sure the mark is in the right place?
Click to expand...

Verified mark with piston stop. Thanks.
 
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