Rotor / Timing

[Liberator 6]

All,
Before removing the old rotor, I made a mark to show where it was pointing. The old rotor came off in pieces, and the new one doesn't point in the exact same spot. For comparison purposes, attached is a picture of where the old one was lined up, and where the new one is lined up. Seems about a 15 degree difference and I do not want valves hitting pistons...

Should I just loosen the distributor and turn so that the new and old one line up? Then check timing?

87 Merc Magnum 350
New motor w/100 hours...

 

[Reel Poor]

Re: Rotor / Timing

I can't imagine why there is a difference. Ignition timing has nothing to do with valve timing (pistons hitting valves) what so ever. Theoretically all you should have to do now is loosen the distributor and move it to near where the original was positioned then set the timing with a light .

 

[Don S]

Re: Rotor / Timing

Make sure the rotor is all the way down on the distributor shaft, then put the cap on and see if it starts. If not turn the distributor till it does, then set the timing with a light.
Like RP says and I mentioned in your other post, the valve timing is not affected by the distributor setting.

 

[Bt Doctur]

Re: Rotor / Timing

you must be mistaken about the marks.there is no way for the replacement rotor to be off that much unless the engine was rotated or the dist was rotated . the rotor has a keyway that sets in the shaft and it does not move.

 

[thrasher]

Re: Rotor / Timing

You are assuming he has the correct rotor arm and that it is correctly installed.. As the others have said, try fitting the distributer cap (don't force it) to make sure the arm is sitting all the way down, then try starting the engine and check your ignition timing with an ignition strobe light. Nothing that you do with the distibutor will effect your valve timing.

Gary

 

[Liberator 6]

Re: Rotor / Timing

The keyway "concept" is valid (it can only go on one way/direction), but the new rotor just didn't have the same angle or offset. I loosened the distributor and turned so that they rotor is pointing in the exact same spot. I got the rotor pressed all the way down on the distributor and the cap fit back on fine. I'm having a hard time starting it now, but as soon as I do, I'll grab the timing light and set her to 8 degrees.

That's assuming I don't get too frustrated and light the boat on fire and push it down the driveway....

 

[Don S]

Re: Rotor / Timing

I loosened the distributor and turned so that they rotor is pointing in the exact same spot. I got the rotor pressed all the way down on the distributor and the cap fit back on fine. I'm having a hard time starting it now

OF course you are having problems. You turned the distributor BEFORE you tried to start it. It would have probably started fine had you not moved it.
Now, turn it till it starts and run, then set it with the timing light.

 

[Liberator 6]

Why does it hate me? I only try to do good...

Why does it hate me? I only try to do good...

My boat is trying to kill me, it's timed at 4 degrees before TDC and still won't start. My ever "helpful" neighbor almost fried the battery cables trying to start it and holding it at a crank, but it refuses. If only I had the same resolve... I hung it up until tomorrow but it amazes me that with this timing I can't get the thing to fire up... Tomorrow, tomorrow, and tomorrow....

 

[Don S]

Re: Why does it hate me? I only try to do good...

Re: Why does it hate me? I only try to do good...

Are you getting spark from the coil wire?

 

[Bt Doctur]

Re: Rotor / Timing

Curious, how did you set it at 4 deg. without running the motor??
might cheat like that with a points system but not a thunderbolt.
like Don says, put it back where it was and start it.

 

[Liberator 6]

Re: Rotor / Timing

350 Magnum Motor wouldn't start so I started working from the battery and onward. I'm not getting anything out of the coil which would be a good reason it won't start. The positive lead on the coil is receiving power, but there is no continuity from the + to the - side of the coil, or from the neg side of the coil to the battery. Also of note, the alarm (goes off after ignition in the "on" position for more than 10 seconds to let you know it's working) isn't going off either.

There isn't a kill cord or anything like that, and the ignition fuse is fine.

Is it okay to run a negative lead from the battery to the neg side on the coil to rule out a bad ground? Also, is there a way to test the coil to see if it's working? Is there is difference b/w Marine and Car coils?

Thanks for all the help -

 

[Don S]

Re: Rotor / Timing

 

[Don S]

Re: Rotor / Timing

PS: Since you have tried to start it, pull the cap back off and make sure everything inside the distributor is ok.

 

[Reel Poor]

Re: Rotor / Timing

Is it okay to run a negative lead from the battery to the neg side on the coil to rule out a bad ground?

Thanks for all the help -

No it is not OK. If you do that you will create a dead short in the ignition circuit.