Ruling out rectifier as source of ignition problems?

[farginicehole]

1989 Evinrude XP150 (E150STLCEM). If I want to rule out my rectifier/regulator as a possible source of some or all of my ignition (no spark on any cylinders now, but sometimes erratic loss on random cylinders) problems, do I need to disconnect the yellow, yellow/gray, gray, red and purple wires that connect to the terminal block from my rectifier? Or do I not need to disconnect all five of these? Thanks!

 

[OBJ]

Re: Ruling out rectifier as source of ignition problems?

icehole....the only thing the rec/reg does is charge the battery. After the engine starts, it's self sustaining. You could remove the rec/reg and start the engine providing the battery is up to crank the starter.

 

[Joe Reeves]

Re: Ruling out rectifier as source of ignition problems?

I'm in total agreement with OBJ. The voltage regulator/rectifier has nothing to do with the ignition system. Your problem is elsewhere.<br /><br />Assuming you have a 35amp charging system, have you checked the black coils on the stator (under the flywheel)? They are the beginning of the ignition system and can be erratic/intermitent in supply the proper voltage to the powerpack(s) should they be melting down due to overheating.

 

[farginicehole]

Re: Ruling out rectifier as source of ignition problems?

Yes, I've visually inspected the stator and didn't see any signs of overheating. I also did the charge coil resistance and output tests as described in my Clymer manual. The resistance between A-B was 942 Ohms and 944 Ohms between C-D. Peak voltage (Fluke 87 and PVA-1 adapter) was 297 between A-B and 278 between C-D, so I think my charge coils are okay. I just read a few places that a failing regulator/rectifier could cause intermittent spark problems, but maybe that just means it can be the root cause of stator damage and subsequent low charge coil output to your pack? <br /><br />Anyways, thanks for the replies guys! I had a thread going titled "'89 Evinrude XP150 spark & starting problems", but I wasn't getting that many replies to it. Maybe it's because in my efforts to give complete details of my troubleshooting tests, I was getting so "wordy" that people didn't have time to read it all!? I'm just trying to be more sure that my timer base is definitely bad before I order the $300 part.

 

[R.Johnson]

Re: Ruling out rectifier as source of ignition problems?

In the trouble shooting section of the Rapair catalog, they twice mention disconnecting the rectifier when checking for a spark problem. I have never been able to understand the connection. Can someone comment on this.

 

[farginicehole]

Re: Ruling out rectifier as source of ignition problems?

For whatever it's worth, I looked for spark today with the red engine harness disconnected and still got nothing on any of the six cylinders. Then disconnected the yellow and yellow/gray wires from rectifier to stator, and still got nothing. I've got very high resistance (6-8 MegaOhms) between my white and purple port & stbd timer base wires, and zero voltage output when cranking from any of the six sensor coils. I think I have a bad timer base, unless someone else has any suggestions before I replace it?

 

[R.Johnson]

Re: Ruling out rectifier as source of ignition problems?

It sounds like you have found the problem with the sensors.

 

[farginicehole]

Re: Ruling out rectifier as source of ignition problems?

That's what I'm thinking. I just didn't know if it seems right that only the purple wires show resistance reading way high, yet all six wires have no voltage output. I really don't know how these things work, so just wanted to see if there is anything else "obvious" I should check before replacing this unit. Thanks for the reply!