just rebuilt runs bad

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Without the MSD box and using the point distributor the engine would not start. It would only fire and sputter.

Had 12V wired to the positive side of coil, distributor wire to negative side of coil, points set around .016, #1 distributor terminal and rotor lined up at 10 BTDC on the compression stroke. Didn't have a ballast resistor or stock coil to use. Thought it should at least start and run.

The engine runs at 45 BTDC initial timing using the points distributor with the MSD box. Same conditions as the MSD distributor and Mopar non-points distributor.

I'm going to go back out now and do it all again just to make sure. Writing this allowed me to chill a little bit first.
 
You may be on the right track. After 30 years of diagnosing driveability problems I have on a couple of occassions found ignition coils where the positive and negative terminals were mismarked.
 
6tfo said:
Without the MSD box and using the point distributor the engine would not start. It would only fire and sputter.

Had 12V wired to the positive side of coil, distributor wire to negative side of coil, points set around .016, #1 distributor terminal and rotor lined up at 10 BTDC on the compression stroke. Didn't have a ballast resistor or stock coil to use. Thought it should at least start and run.

The engine runs at 45 BTDC initial timing using the points distributor with the MSD box. Same conditions as the MSD distributor and Mopar non-points distributor.

I'm going to go back out now and do it all again just to make sure. Writing this allowed me to chill a little bit first.
Click to expand...

MAKE SURE the points distributor has a GOOD "condenser" in it. Cheap to replace even if there is one in there.

(A "new" condenser does not mean "good.")

I would not run the engine for very long (5 minutes) without a ballast rigged up.

You should be able to "test bench" your points system by hooking up the following:

Battery/ clip lead---to coil positive, coil negative to distributor, distributor case to battery negative. "Rig" a spark gap, maybe even a plug and plug wire, from the coil tower to battery neg. (Ground) You should be able to TURN distributor by hand, even slowly, AND IT SHOULD make hot sparks.

They are cheap to buy at any parts store. If you have a Mopar electronic ballast, use that. If it's a 4 terminal, the two "halves" are different." Post back, I'll explain the proper way to use a 4 term. ballast with points.

I can NOT STRESS ENOUGH how important I believe it to be, to get your car running RIGHT WITH OUT the MSD stuff. It very well could be that it is introducing some delay in timing, or multiple triggers (false spark) that is causing part/ all of the problem

One more time, you should be able to "power time" the engine at a KNOWN degree figure of about 35* AND IT SHOULD RUN there with no more fuss.
 
67Dart273 said:
MAKE SURE the points distributor has a GOOD "condenser" in it. Cheap to replace even if there is one in there.

(A "new" condenser does not mean "good.")

I would not run the engine for very long (5 minutes) without a ballast rigged up.

You should be able to "test bench" your points system by hooking up the following:

Battery/ clip lead---to coil positive, coil negative to distributor, distributor case to battery negative. "Rig" a spark gap, maybe even a plug and plug wire, from the coil tower to battery neg. (Ground) You should be able to TURN distributor by hand, even slowly, AND IT SHOULD make hot sparks.

They are cheap to buy at any parts store. If you have a Mopar electronic ballast, use that. If it's a 4 terminal, the two "halves" are different." Post back, I'll explain the proper way to use a 4 term. ballast with points.

I can NOT STRESS ENOUGH how important I believe it to be, to get your car running RIGHT WITH OUT the MSD stuff. It very well could be that it is introducing some delay in timing, or multiple triggers (false spark) that is causing part/ all of the problem

One more time, you should be able to "power time" the engine at a KNOWN degree figure of about 35* AND IT SHOULD RUN there with no more fuss.
Click to expand...

I'm getting the point (no pun intended) about getting back to basics. Unfortunately I think I'm as basic as the ignition gets and the engine doesn't run.

So let's say the MSD is compensating for a problem and the engine runs fairly well at 45 BTDC. With stock ignition (get the point) the engine doesn't even start. What may be the problem? Thanks.
 
I suggested earlier, might be a bad condenser. There are only a few component, here

A good coil, and hopefully, a matching resistor

A good strong battery supply

A distributor, with properly opening and closing points

A good condenser.

You can easily check if the points are set, just look at them, and use a feeler. Use a light to determine they are actually opening / closing.

Use a clip lead direct to the battery to eliminate wiring harness problems

If you are sure you have a good coil, good battery voltage, and the points are doing their job and NO SPARK, then its time to gamble and change the condenser.
 
At this point maybe you should look at something else.
If would appear that you have ruled out the ignition if it won't run with just the point distributor, although without a ballast resister it will burn up the points in no time.
You need to make sure your cam was installed properly and it can be done without taking it apart. It should be accurate enough
That cam's intake valve should be opening about 34 deg before TDC on the intake stroke.
Pull the valve cover and while rotating the engine manually stop as soon as you see the #1 intake valve start to open and stop turning the engine. Go slowly.
Look at the balancer and measure to see how close to 34 deg BTDC you are sitting. It should be close.
If it's way off the cam is not in correctly.
 
He's already checked cam timing, and it's spot on..

You are timing this thing off the front cylinder Drivers side??? sorry,, just had to ask..
 
67Dart273 said:
I suggested earlier, might be a bad condenser. There are only a few component, here

A good coil, and hopefully, a matching resistor

A good strong battery supply

A distributor, with properly opening and closing points

A good condenser.

You can easily check if the points are set, just look at them, and use a feeler. Use a light to determine they are actually opening / closing.

Use a clip lead direct to the battery to eliminate wiring harness problems

If you are sure you have a good coil, good battery voltage, and the points are doing their job and NO SPARK, then its time to gamble and change the condenser.
Click to expand...

The engine is firing so it must have spark. I'm going to round up a stock coil, ballast resistor and another condenser.
 
kman521 said:
At this point maybe you should look at something else.
If would appear that you have ruled out the ignition if it won't run with just the point distributor, although without a ballast resister it will burn up the points in no time.
You need to make sure your cam was installed properly and it can be done without taking it apart. It should be accurate enough
That cam's intake valve should be opening about 34 deg before TDC on the intake stroke.
Pull the valve cover and while rotating the engine manually stop as soon as you see the #1 intake valve start to open and stop turning the engine. Go slowly.
Look at the balancer and measure to see how close to 34 deg BTDC you are sitting. It should be close.
If it's way off the cam is not in correctly.
Click to expand...

I verified earlier by overlapping valves over cylinder #6 and checking the balancer timing mark. It was 1/8 inch from the zero on chain cover. I will also try the method you suggested. Thanks much.
 
inertia said:
He's already checked cam timing, and it's spot on..

You are timing this thing off the front cylinder Drivers side??? sorry,, just had to ask..
Click to expand...

Yes, cylinder closest to grill on drivers side. Don't be sorry, at this point I'd love it to be something simple that I overlooked. Thanks.
 
I gotta hang around for the end of this one. You dont say where your located. Maybe someone close that can drop by and assist. I'm bad about stopping by Oriellys to let the knowledgeable guys check things out with their meters. I'll be watching with great anticipation.
Small Block
 
Small Block said:
I gotta hang around for the end of this one. You dont say where your located. Maybe someone close that can drop by and assist. I'm bad about stopping by Oriellys to let the knowledgeable guys check things out with their meters. I'll be watching with great anticipation.
Small Block
Click to expand...

My name is "Duff" and I live in Lusby, Maryland. The car is at my brothers house in Bowie, Md.

I'm putting together a summary of everything we've done so far that I will post soon.

Thanks.
 
1) Problem recap:
- The motor only seems to run well at 45 BTDC initial timing. It idles okay and has nice throttle response. When I increase RPM I can watch the timing advance more than 20 degrees (total 65 or higher). It runs poorly when timing is set anywhere near where it should be (12 - 20 BTDC initial)

2) Ignition:
MSD 6AL
MSD Blaster Coil
MSD Distributor
New MSD Plug wires
New Autolite plugs

3) Using the above MSD ignition:
- Verified TDC using a piston stop
- Verified both intake and exhaust valves closed at TDC compression stroke.
- Verified at TDC that rotor is pointing to the number one spark plug terminal.
- Set 15 BTDC and aligned rotor to #1 plug wire
- Verified spark plug wire properly configured to plugs in a clockwise firing order 18436572
- To check cam installation. Verified #6 cylinder valve overlap is within a half inch of the timing mark. It was about an eighth.
- Compression is consistent between 135 and 145
- Isolated MSD Box and wiring away from other wires to the extent possible.
- Grounded and powered MSD box direct with battery
- Locked out advance on MSD distributor. Reconfigured it after initial timing test were unsuccessful.
- Verified MSD orange to Coil positive and MSD black to coil negative
- Verified proper wiring of MSD connection to distributor
- Used basic inductive timing light and inductive degree adjustable timing light.
- Checked for vacuum leaks, around manifold, carb base, and carb ports.
- Tried 2 different carbs

4) Using MSD box and coil with a stock 318 magnetic pick up distributor. Same problem, motor only runs well with 45 BTDC initial timing.

5) Using MSD Box and coil with a new rebuilt stock points distributor. Same problem, motor only runs well with 45 BTDC initial timing.

6) Removed MSD box, ran stock points distributor with MSD coil. Engine fired but would not start.
- Didn't have stock coil or ballast but will by this Friday
- Ran wire from battery positive to coil positive
- Ran coil negative to black distributor wire.
- Verified point gap.
- verified TDC compression stroke
- Verified spark plug wiring and proper firing order
- Tried starting with rotor pointing towards #1 plug and timing mark 15 BTDC, 10 BTDC, 5BTDC, and TDC. No luck.

7) Other notes, most I haven't posted because I thought they would be a distraction, but maybe not:
- The machine shop is primarily Chevy
- I had the machine shop change timing chain covers. The old one had timing marks on the passenger side, the replacement has timing on the drivers side.
- The machine shop didn't like the new rocker assembly that I provided saying the kit wasn't machined well and they convinced me to use rockers made by Comp Cam.
- The machine shop told me they were unable to degree the cam using the Mopar Performance timing chain and gear kit that I provided. Said it was a defect.

I'm not trying to point fingers at the machine shop here. They spent hours on the phone with me. They've wanted me to go back to the stock ignition, which now I have without success. Unless something good happens I will be back in touch with them on Friday after I install the stock coil, and ballast.

I've read every post in this thread at least twice and sometimes more.

This will really be embarrassing if it ends up I'm doing something stupid but I can deal with that if the engine is running like it should.

Thanks for reading.
 
You might be on to sumthin Chevy machine shop! I think you have a nice car!! watched your video I hope you get it figured out!
 
So, when machine shop changed the timing cover,, did you change damper,, remark it,, or how did you compensate for the mark?

when finding #1 tdc with a positive stop, you rotated crank to the stop,, then reversed to the stop,, and split the difference, right??
 
inertia said:
So, when machine shop changed the timing cover,, did you change damper,, remark it,, or how did you compensate for the mark?

when finding #1 tdc with a positive stop, you rotated crank to the stop,, then reversed to the stop,, and split the difference, right??
Click to expand...

The machine shop cut an new notch with white paint over it to line up with the new timing cover.

Yes, on using the stop steps above. Did this probably three times and will do it again on Friday. I have to admit that didn't actually measure, just eyeballed it. If not spot on it's very close.

Thanks.
 
inertia said:
I'm thinking there's somthing not right here
Click to expand...

Yeah, I brought the timing chain kit up with the Machinist. I heard him asking another machinist if he recalled working on it. They pulled out notes and explained what they did and why they thought it was bad. Unfortunately technically I wasn't able to follow him. Probably could now though, after all this, I've learned quite a bit.

Thanks.
 
Yep,, that's all good then, including cam timing, . . man I wish I was there,,,

next time you time it,, try timing it on #6 cylinder,, It should be the same,, but just for yuks..?.
 
inertia said:
Yep,, that's all good then, including cam timing, . . man I wish I was there,,,

next time you time it,, try timing it on #6 cylinder,, It should be the same,, but just for yuks..?.
Click to expand...

Will do. Thanks.
 
I'm just going to throw this out there because my brains starting to get fuzzy-er,, maybe someone else can straighten this idea out,,

If you're advancing it 45 degrees at the crank, that's going to be 22 1/2 at the cap , your rotor is half way to the next plug wire contact, so a stock ignition likely won't make the jump,, and with the old MSD system,, wouldn't you be hearing a tremendous snap as the spark jumped from rotor to cap,... hmmmm?

by the way,, I watched the video,, it sounds great, something is just wacky.. grant

Is the dizzy cap locator right, or is cap twisted somehow? or rotor locator broken, rotor twisted, rotor end contact bent??
 
inertia said:
I'm just going to throw this out there because my brains starting to get fuzzy-er,, maybe someone else can straighten this idea out,,

If you're advancing it 45 degrees at the crank, that's going to be 27 1/2 at the cap , your rotor is half way to the next plug wire contact, so a stock ignition likely won't make the jump,, and with the old MSD system,, wouldn't you be hearing a tremendous snap as the spark jumped from rotor to cap,... hmmmm?

by the way,, I watched the video,, it sounds great, something is just wacky.. grant

Is the dizzy cap locator right, or is cap twisted somehow? or rotor locator broken, rotor twisted, rotor end contact bent??
Click to expand...

I would think if the timing is really at 45 initial and 60 total the distributor would be firing the wrong plug when he revs it up.
That timing mark has to be wrong or both timing lights are screwed.
 
If it doesent run with the point ignition set to around TDC it almost has to be cam timing might even be something like an incorrectlly ground cam but unlikely. Why was the shop unable to use your timing set?
 
kman521 said:
I would think if the timing is really at 45 initial and 60 total the distributor would be firing the wrong plug when he revs it up.
.
Click to expand...

Exactly,,, path of least resistance, to the cylinder with less compression/density..

or the rotor is somehow late.. maybe.. My head feels like I just downed a slushy.... aaaargh.... lol

looking forward to new dizzy, cap, etc
 
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