EVINRUDE 70hp still misfiring

[BMAN]

'79 model intermittent misfiring (no spark to plug) on the top cylinder. i have put new coil on this cylinder, replaced power pack, replaced stator, replaced rectifier, checked flywheel for loose magnets and it looks ok to me. i have checked all the wiring and connections in the ignition. i put it the shop before i replaced these parts and the mechanic rebuilt the carbs. it has a one year old fuel pump. the only thing i think i haven't tried now is the timer base. anyone have any other ideas?

 

[12Footer]

Re: EVINRUDE 70hp still misfiring

It has to be the switch box,providing the plug is not dry. If it is wet, it's the coil (you replaced that) or the switch box not sending signal to coil.<br />Look for a ground-path at the plug and plug wire also.<br />That's about all it can be. good luck,and tight linez.

 

[BMAN]

Re: EVINRUDE 70hp still misfiring

i disabled the kill wire from the powerpack (black/yellow stripe). still not getting spark to top cylinder. is this a good test for bad switch or should i try something else? thanks

 

[BMAN]

Re: EVINRUDE 70hp still misfiring

still looking for help. i have a used timer base on the way to try. i hope that does it. i don't know what else to try and i can't trust my local marina. please help, thanks

 

[BMAN]

Re: EVINRUDE 70hp still misfiring

i rechecked all the grounds on the coils and the pack and got it to run good again. i thought it was fixed. when i got home from work (8hours later) i started it again and it was not firing again. i haven't got my used timer base in yet to try it. if that doesn't do it i give up. i'll just get rid of it. please help.

 

[12Footer]

Re: EVINRUDE 70hp still misfiring

One thing you can try before your timer base, remove the pplugs, and switch them. See if the dead cylinder follows a bad plug.<br />Just to be sure it's not an arcing plug.

 

[john0974]

Re: EVINRUDE 70hp still misfiring

hey mate i also have a70hp envirude with same problem u sound like u have the same lazy mechanic as myself we have had coils replaced,plugs replaced,wiring checked,checked leads at nite for a spark out all timing is set fine carbie`s r all clean,has 121 compression in all cylinders,did u ever have any luck with urs mate mine motor runs fine once ur going but when idling has a misfire

 

[CharlieB]

Re: EVINRUDE 70hp still misfiring

Souonds like you have spent a lot of money on parts before learning how to troubleshoot an ignition system.

Sorry for the sarcasm, but.....

A DVA meter can be your best friend when electrical gremlins get into your motor.

CDI Ignitions have a wonderful outboard ignition troubleshooting guide posted free on their site, a copy is also somewhere here on iboats, I just don't know the correct address.

TEST, TEST, and TEST again!!!!!!!

The DVA meter will SHOW YOU (I'm in Missouri, the 'Show Me' State) which part is at fault.

Save all those old parts, many are still good and will have some value when the need arises.

 

[tx1961whaler]

Re: EVINRUDE 70hp still misfiring

You have resurrected an 8 year old thread. I'm sure he fixed it by now.....