Only runs 40 Degrees advanced

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I went thru that once but spotted it almost right away. Just an Orange box.
I replaced a faulty factory pick-up and it wouldn't start until I rotated the D a huge amount. Then it wouldn't take throttle. I put the Timing light on it and saw the coil firing all over the place and randomly dropping sparks as I tried to increase the rpm. I had a polarity reversing jumper in the glovebox and a few minutes later was back on the hiway.
When I got home later I compared the freshly installed pick-up to another spare one, and saw that the wire colors were different. That was the AHA!-moment.
All my other SBM distributor pick-ups had one Orange wire. Except the one LeanBurn in the box;which was brown,(or was it gray? now I forget but it wasn't Orange lol), like the one I had installed. Needless to say I put an Orange-wired spare, back in the glovebox.
 
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There is a polarity of the distributor sensor wires. If you have them reversed, it will be AFU. The distributor trigger will be between the reluctor teeth, and the phasing at the cap between terminals.
A correct trigger at distributor happens as reluctor tooth is passing off pickup nub.

A quick check, rotate crank to 40 deg, look in distributor to see pickup nub in relation to reluctor teeth, if not near tooth...polarity is wrong. Fix that, re-time with static setting. Set crank to 13 btdc, rotor at #1, rotate distributor, so as crank just passes 13, the reluctor tooth 1/2 off pick up nub. Tighten hold down. Crank it up, use the light, it should be within 1 to 2 degrees of desired setting.
That is an interesting thought before I had everything plugged together with the sniper wiring and it was doing this now I have a MSD distributor and I will check that polarity But it does act like that is possible
 
Before you take the engine apart to check the cam timing, you can do it with just the valve cover off.

Run try number 1 cylinder to cross over (overlap) and look at the rockers.

If both are open the same, the cam is in straight up. If the exhaust is open more, the cam is retired. If the intake is open more the cam is advanced.

Unless the cam is way off, you only see .010-.015 difference at most. If it's more than that, you be probably bet the cam is off.

Again, be leery of living and dying by the A/F meter. I've seen them read differently between the same brand. Different across brands. Move the sensor in th collector and it can affect the reading.
 
There is a polarity of the distributor sensor wires. If you have them reversed, it will be AFU. The distributor trigger will be between the reluctor teeth, and the phasing at the cap between terminals.
A correct trigger at distributor happens as reluctor tooth is passing off pickup nub.

A quick check, rotate crank to 40 deg, look in distributor to see pickup nub in relation to reluctor teeth, if not near tooth...polarity is wrong. Fix that, re-time with static setting. Set crank to 13 btdc, rotor at #1, rotate distributor, so as crank just passes 13, the reluctor tooth 1/2 off pick up nub. Tighten hold down. Crank it up, use the light, it should be within 1 to 2 degrees of desired setting.
I am checking wire colors this morning. The MSD has a black and black with orange tracer coming out of it orange meaning positive that wire is hooked to the violet on the extension that goes to the box and the plugs match up there with the violet going to Violet and the green going to green. So they are color matched all the way from the MSD to the box. Now the hyper spark connectors look reversed to me but I ask on the sniper Facebook site and the guys looked it up and said no that’s right they switch at the distributor and both of them was the same I have had to hyper spark distributors so far both of them act the same As this MSD does.

35C97515-D547-4F93-BF5C-6468185F85A6.jpeg
 
@yellow rose - Can you explain this part more?


Roll the crank to TDC number 1 firing. Then roll the crank exactly 180 degrees more and you are on the overlap stroke for that cylinder.

Then just look at the rockers. It will give you a clue as to where the cam is installed.

Years ago, I was in a 2 man shop. We were so busy, we hired a guy who was a customer to help out. He couldn't run a machine, but he could clean parts and we knew he had done some assembly.

I had a rule. Any engine I put together the cam gets degreed. Every engine. Every time. Always. This was explained to him. I said don't screw my customers because I charge for it. So if you don't degree the cam, the customer is getting billed and you'll be screwing him twice. Once for charging him for something he didn't get, and screwing him for not doing it.

I had a vacation coming up and we had a Ford Stroker going together. We decided to let this guy do it. I again told him degree the cam. He said I will.

The engine was gone by the time I got back. I said, did you degree the cam??? He says sure did.

A few days later, the customer calls and said the engine won't fire. I'm like WTF??? So I say check a couple of things and call me back. Nothing I suggested worked.

So I have to climb into the car and drive over to the customer. I look at a couple of things and I'm thinking why won't this pig start? So he turns it over and I can tell it ain't right.

We jerk the valve cover off and check valve opening at overlap. Either my guy didn't degree the cam, or he screwed up. I could see the exhaust valve was off the seat like .050 more than the intake. That means the cam was retarded.

So...now we are losing money. I tell him let's jerk the engine, which I stay and help and put his engine in the trunk of my car. Get it back, on the stand and show the guy what I found. He says bullshit. You can't tell anything by that. I degreed the cam and its spot on.

Take the front off and degree the cam. It's like 11 degrees retarded. So, either he lied and didn't do it, or he did and didn't have a clue as to what he was doing.

The moral of the story is always degree the cam. If you're not sure of your numbers. Throw the head and rockers on number one and check.

Needless to say, I showed his *** the door.
 
In post #48, tried to give you a method to test, static setting of 40 deg, looking at reluctor, pick up nub.

I am checking wire colors this morning. The MSD has a black and black with orange tracer coming out of it orange meaning positive that wire is hooked to the violet on the extension that goes to the box and the plugs match up there with the violet going to Violet and the green going to green. So they are color matched all the way from the MSD to the box. Now the hyper spark connectors look reversed to me but I ask on the sniper Facebook site and the guys looked it up and said no that’s right they switch at the distributor and both of them was the same I have had to hyper spark distributors so far both of them act the same As this MSD does.

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In post #48, tried to give you a method to test, static setting of 40 deg, looking at reluctor, pick up nub.
I tried that and with the MSD distributor I couldn’t see it so I am trying a stock distributor because the reluctor is easier to see haven’t got that changed out yet. But it sounds like something that would make it run this way
 
I have no idea about MSD distributor. If it is variable reluctance, then what I said could be possible. If it is optical, then that is different, no way what i said, could be true. So it would be something else, and no idea what.
 
I have not seen anywhere in this thread where you've VERIFIED TDC WITH A PISTON STOP. That is the ONLY way to 100% verify TDC. Simple to do, quick to do, little to no cost......and I've not seen it done which would have been my FIRST move. ESPECIALLY after the engine "backfired, ran backwards and never ran again".......your words.

I've seen that happen before, three times. ALL THREE TIMES the timing chain jumped. One was with a Cloyes Billet double roller. "If you don't think" it can happen, you gotta 'nuther thing coming. "All bets are off" unless you 100% VERIFY tdc with a piston stop.
 
I have no idea about MSD distributor. If it is variable reluctance, then what I said could be possible. If it is optical, then that is different, no way what i said, could be true. So it would be something else, and no idea what.
Yes the MSD pro billet is a magnetic distributor. But I just couldn’t see the pick up coil and the reluctor clearly. So now I tried to stock distributor it is easy to see I set it up at 13° nothing happened I checked first bar it wasn’t triggering the MSD box so I pull it out and spin it by hand And it throws fire like hell I put it back in and it doesn’t just more weird stuff with this motor I’m getting really tired of it
 
I have not seen anywhere in this thread where you've VERIFIED TDC WITH A PISTON STOP. That is the ONLY way to 100% verify TDC. Simple to do, quick to do, little to no cost......and I've not seen it done which would have been my FIRST move. ESPECIALLY after the engine "backfired, ran backwards and never ran again".......your words.

I've seen that happen before, three times. ALL THREE TIMES the timing chain jumped. One was with a Cloyes Billet double roller. "If you don't think" it can happen, you gotta 'nuther thing coming. "All bets are off" unless you 100% VERIFY tdc with a piston stop.
I did not use a piston stop but I did pull the intake and number one head and watch the piston it lined up with the mark on the timing cover and I did check the chain because I thought it jumped but when I pulled it apart it was still dot to dot just like I put it in four years ago. It is a Cloyes chain Seemed loose when I put it in. So I put on a chain tensioner when I put it back together. Maybe it was Line bored when I rebuild it way back I don’t remember. Another guy was telling a way to see if the cams lined up by the valves I’m thinking about taking the valve cover off and looking at it that way before I take the motor apart again
 
I did not use a piston stop but I did pull the intake and number one head and watch the piston it lined up with the mark on the timing cover and I did check the chain because I thought it jumped but when I pulled it apart it was still dot to dot just like I put it in four years ago. It is a Cloyes chain Seemed loose when I put it in. So I put on a chain tensioner when I put it back together. Maybe it was Line bored when I rebuild it way back I don’t remember. Another guy was telling a way to see if the cams lined up by the valves I’m thinking about taking the valve cover off and looking at it that way before I take the motor apart again

"Dot to dot" is not TDC. It is 180 out, or TDC for #6. TDC for #1 is cam gear dot at 12 and crank gear at 12. So you need to make SURE your distributor is in correctly. Also, have you run a compression test?

Even still, WITHOUT USING A PISTON STOP, you do not know "where you are". Ask me how I know.
 
I will tell you that I have had two hyper spark distributors and one MSD distributor in it and they all do the same thing if they are set up exactly by the book with about 10 or 15° initial they will not fire at all totally dead. their is spark going to the distributor but none coming out and when you quit cranking That makes a spark when you turn the key off then it lights and has tried to run backwards several times if you turn the distributor up to 35 or 40° it starts and sounds real good like it’s all fixed until you try to back the timing back down to normal then it stumbles and dies.
This all started when the distributor got locked up and bent the shaft it hasn’t ran right sense.
 
"Dot to dot" is not TDC. It is 180 out, or TDC for #6. TDC for #1 is cam gear dot at 12 and crank gear at 12. So you need to make SURE your distributor is in correctly. Also, have you run a compression test?

Even still, WITHOUT USING A PISTON STOP, you do not know "where you are". Ask me how I know.
I agree I say dot to dot because that is how the manual tells you to line it up. If both darts are at 12 o’clock then it is top dead center for number one. If the darts are at 12 and six then it is at top dead center for cylinder six that is very confusing but I learned that the hard way a few years back. I am thinking eyeballing the top side of number one piston and top dead center on the timing cover and balancer can’t be no more than a couple of degrees out and this problem appears to be 30 or 40° out. If it was possible I would say that Cam is twisted but we all know that’s impossible it would just break like a piece of hard candy
 
I agree I say dot to dot because that is how the manual tells you to line it up. If both darts are at 12 o’clock then it is top dead center for number one. If the darts are at 12 and six then it is at top dead center for cylinder six that is very confusing but I learned that the hard way a few years back. I am thinking eyeballing the top side of number one piston and top dead center on the timing cover and balancer can’t be no more than a couple of degrees out and this problem appears to be 30 or 40° out. If it was possible I would say that Cam is twisted but we all know that’s impossible it would just break like a piece of hard candy
"Dot to dot" is not TDC. It is 180 out, or TDC for #6. TDC for #1 is cam gear dot at 12 and crank gear at 12. So you need to make SURE your distributor is in correctly. Also, have you run a compression test?

Even still, WITHOUT USING A PISTON STOP, you do not know "where you are". Ask me how I know.
Maybe this will make some sense
OP reports it runs at 30 - 40 degrees initial timing, let us assume 35 degrees.
Correct initial timing should be close to 15 degrees.
Camshaft operates at 1/2 crank shaft rpm = .5
The simple math
35-15=20 degrees of crank rotation
20
x.5 =10 degrees of cam rotation
10 degrees of cam rotation
could easily represent the timing chain has skipped a tooth on the cam sprocket.
In this situation the TDC mark on the balancer would still show to be correct but would give you a false timing condition.
If I am wrong tell me.
 
Maybe this will make some sense
OP reports it runs at 30 - 40 degrees initial timing, let us assume 35 degrees.
Correct initial timing should be close to 15 degrees.
Camshaft operates at 1/2 crank shaft rpm = .5
The simple math
35-15=20 degrees of crank rotation
20
x.5 =10 degrees of cam rotation
10 degrees of cam rotation
could easily represent the timing chain has skipped a tooth on the cam sprocket.
In this situation the TDC mark on the balancer would still show to be correct but would give you a false timing condition.
If I am wrong tell me.

Nope. That's exactly right and is WHY I keep on keepin on with finding TRUE TDC. Too many times people THINK they've found it "WHEN THEY AIN'T".
 
Maybe this will make some sense
OP reports it runs at 30 - 40 degrees initial timing, let us assume 35 degrees.
Correct initial timing should be close to 15 degrees.
Camshaft operates at 1/2 crank shaft rpm = .5
The simple math
35-15=20 degrees of crank rotation
20
x.5 =10 degrees of cam rotation
10 degrees of cam rotation
could easily represent the timing chain has skipped a tooth on the cam sprocket.
In this situation the TDC mark on the balancer would still show to be correct but would give you a false timing condition.
If I am wrong tell me.
I did not know the math but I agree with you. That’s why I pulled the timing cover to check the alignment because I thought that is the only thing that could’ve given. But when I did it was still dot to dot lined up and I was expectIng that to be off or a keyway to be Sheared but everything looked fine. But I have to agree it is somewhere in the cam timing I may have to take it out to find it.
 
I did not know the math but I agree with you. That’s why I pulled the timing cover to check the alignment because I thought that is the only thing that could’ve given. But when I did it was still dot to dot lined up and I was expectIng that to be off or a keyway to be Sheared but everything looked fine. But I have to agree it is somewhere in the cam timing I may have to take it out to find it.
You did say your chain was loose before you added the tensioner?
 
You did say your chain was loose before you added the tensioner?
Yes for some reason I put a sealed power timing chain set on some years ago and it seem loose when I put it on so about four years ago I change the cam and I put a cyoles timing set on and it was still looser than I would like but I put it on and ran it just fine until now so when I pulled it apart to check The alignment I put a cyoles chain tensioner on also.
 
The cam could be broken, but I think that it would be pretty obvious by now. The fact that the distributor is still turning would seem to rule it out, but stranger things have happened. I could envision it breaking yet still driving the distributor and oil pump somehow.
 
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