Setting Timing

[patrickt]

Had anybody worked on the engine in between when it left the engine builder and when you started tweaking the timing... and the other stuff?

[Gaz64]

Originally Posted by patrickt

Had anybody worked on the engine in between when it left the engine builder and when you started tweaking the timing... and the other stuff?

That's a good point as well.

Did a nut get dropped down the carburetor by accident?

Did the spark plug look normal on removal?

If valve to piston clearance becomes an instant negative, something has to give.

[Bernica]

Originally Posted by Gaz64

That's a good point as well.

Did a nut get dropped down the carburetor by accident?

Did the spark plug look normal on removal?

If valve to piston clearance becomes an instant negative, something has to give.

Yup. There are only two ends to look at and I doubt it was the cam. Maybe wrong, but that's my guess...

[Large Arbor]

I have now had the intake off again and there was nothing in the intake. I did start it once with the carb returns springs off and it hi revved and I shut it off immediately (seconds). I think that was when the pushrod came out because I did not have it seated just right. I made sure they all were seated well when putting it back together. There is nothing in the carbs or intake and I can attest to that.


Not sure of the cause, but now it appears I have an electrical gremlin. I can start but am only firing on two cylinders (2 and 6). I am thinking the MSD 6AL box is bad.

Any other thoughts as to what may cause this?

Phil

[patrickt]

Originally Posted by Large Arbor

Not sure of the cause, but now it appears I have an electrical gremlin. I can start but am only firing on two cylinders (2 and 6). I am thinking the MSD 6AL box is bad.

Any other thoughts as to what may cause this?

No. A faulty MSD box is not going to result in only the same two out of eight cylinders firing on each rev. That sounds more like an improperly installed distributor/cap/rotor problem.

[Large Arbor]

That has been checked twice. Rotor button can only go on one way, square hole and round hole sets the rotor button position. Plug wiring and firing order also checked. Coil maybe?

Phil

[Bernica]

When you had the intake off did you inspect all of your lifters and the cam lobes? Also, how hi did you "hi-rev" the engine? Up to the rev limiter?

[patrickt]

Originally Posted by Large Arbor

That has been checked twice. Rotor button can only go on one way, square hole and round hole sets the rotor button position. Plug wiring and firing order also checked. Coil maybe?

Phil

No, it's not the coil either. Let me get this straight: If you put a timing light on plug #2 or #6 and crank or run the engine the light blinks normally. But if you do that for any of the other six cylinders you get no blink, indicating no current at all through those spark plug wires, correct?

[Bernica]

Did you check the little carbon button inside center of the distributor cap? A common problem with the MSD caps...

[Large Arbor]

The lifters were fine. When it fired, you could feel the headers and only 2 and 6 were firing. Initially more were, but with the last try only 2 and 6.

Phil

[Large Arbor]

I brought the balance around to TDC. I will check #1 plug to see if it is up. The rotor button is pointing a little after (counter clockwise) from #1. Rotor button is pointing between #1 and #5.

Phil

[Bernica]

Originally Posted by Large Arbor

I brought the balance around to TDC. I will check #1 plug to see if it is up. The rotor button is pointing a little after (counter clockwise) from #1. Rotor button is pointing between #1 and #5.

Phil

I was referring to the little black carbon button up inside the cap, not the rotor itself.

[Large Arbor]

I assume you area referring to this button.

[Bernica]

Yes. Is the button still spring loaded? It should move when you press down on it. Sometimes they get stuck and sometimes they break off...

[Large Arbor]

Yes, I checked it, still spring loaded.

Phil

[Large Arbor]

I am just not sure what to replace next. Distributor is new and worked fine last week. Cap is new. The coil will arc across the terminals if I leave the key on for a period of time, but I understood that to be common as the MSD's build up lots of current.

Phil

[1795]

Originally Posted by patrickt

No, it's not the coil either. Let me get this straight: If you put a timing light on plug #2 or #6 and crank or run the engine the light blinks normally. But if you do that for any of the other six cylinders you get no blink, indicating no current at all through those spark plug wires, correct?

I would go back to Patrick's question first, do you have current at all lot the wires? It seems odd that the second two cylinders are the only ones firing. I will have to think about that one for a while and get back to you. I would say to check plugs to verify that they all are good, they are quite fragile and if dropped can stop working correct, but the odds that the only two good plugs ended up across from each other is not likely.

2 & 6 are right next to each other on the cap. I wonder if something is wrong with the cap? Phil, I think that you need to rule out one thing at a time. My guess would be more electrical than mechanical, unless somehow when the engine revved real high the timing chain slipped or somehow the distributor gear slipped. But that does not seem likely. Did you hit the rev limiter when the engine over revved? Could there be something that needs to be re-set in the MSD box? It would not seem likely that something would have to be re-set.

[Large Arbor]

I just did the MSD test for the ignition and it is firing correctly.

Phil

[Bernica]

Does that mean it's running now?

[Large Arbor]

No, I just did MSD's check to be sure it was firing. I also pulled the distributor to look at it. I cannot see anything wrong with it visibly. The drive rod for the oil pump came with it again. I got a straw and gently put it back in. This is the third time that has worked.

I will call MSD tomorrow and see what they say. I do not know what to except reset the distributor and try again. Hopefully I will get some answers over the next couple of days.

Phil