1973 evinrude 85hp firing twice on same cylinder

[Little Richard]

Marked firing sequence on top of fly wheel. When putting timing light on plug wires 1,2,and 4 it's good. When on number 3. It shows to be firing on 1 and 3. When warm compression test 120 on all. Strong consistent spark after changing power pack and couple coils. Jumps 1/2 inch gap. Replaced a bad rectifier. Put IR temp gun on exuahst cover behind #1 cylinder and noticed it was running 20 degree hotter than rest and often seems to be running leaner looking at plugs. ( more dry and more white). So my question is am I getting double firing on number 1 and why? Could it be timer base? From black/whites to white/blacks I get 1.2 volts on DVA.

 

[Little Richard]

Could power pack already be damaged from some other issue. Just put it on and idled it for 20 minutes while checking stuff

 

[boobie]

Could you have the timing lite pick up to close to another cylinder ??

 

[Little Richard]

I'll check in the morning and post back. I've been wondering about arcing too. Coil packs are used and not new. But working good on spark gap test

 

[Bosunsmate]

Highest cylinder always seems to run hotter on these, forgotten which number cylinder that is.
Not sure what your problem is with this engine

 

[Little Richard]

Today, 01:11 AM
Checked for arcing while dark. None. When I first started it with engine cool there was no apparent double fire on #1. With wires separated away from each other. Once engine warmed up and with timing light on #3 wire the #1 started to show up. The more it warmed up the more double firing showed up on timing light. Definitely sounds like electrical component. Stator ohmed at 660 which is low according to manual. DVA was 205v at idle if I remember correctly. Seems good. Sensor coil leads from timerbase ohmed at 8.3 (good). I'm thinking power pack is bad even though it's new. Don't know if timer base could create this problem or be damaging power pack?

 

[Little Richard]

Engine idles rough. Sprayed starting fluid around carb gaskets rpms dropped. Small amount of fuel around carbs can't tell exactly where it's coming from. But that's sounds like another thread and possible lean condition on #1. Don't think that has relevance to current issue though

 

[Little Richard]

When trying to follow cdi test procedures for voltage at off trigger with DVA my Klein cl3200 rated for 600v goes blank? Tried testing from black/whites to white/ blacks and from each to ground with motor at idle. Voltmeter goes blank. Possible to much voltage? Or maybe I'm not understanding procedure correctly.supposed to be between 150-400v?

 

[Little Richard]

Sorry from black/whites to white/ blacks I'm getting 1.2v. It's when I'm testing them to ground that voltmeter goes blank. Should I be testing leads while disconnected

 

[Bosunsmate]

check you arent getting a short to ground on them, thats a common developed fault on the wire from under the flywheel necklace

 

[Little Richard]

When I ohmed them each to ground I got infinity. But I'll take a better look and wiggle them while checking resistance.Might take the flywheel off and take a peek under it tonight

 

[Little Richard]

Took fly wheel off stator looked real good. Flywheel magnet all looked good. Took off stator and trigger . Inspected wiring off trigger. Looked good. Checked for grounding on wires with ohm meter got infinity. Idk. I'm almost thinking a bad new power pack. Everything is firing good and strong and consistent. Just seems to double fire on #1 according to timing light. Possibility is timing light some how picking up spark off #1 when it's on # 3 doesn't appear to be arching anywhere. Swapped coiled around same results. Fooee

 

[Little Richard]

I'll have to say with trigger off I did see one wire with insulation worn thin where it goes thru clamp on trigger. No wires showing. I wouldn't think that would be an issue

 

[Bosunsmate]

Well any continuity between that wire and any other on that trigger?

 

[Little Richard]

None.

 

[Bosunsmate]

well powepack sounds like best option then

 

[Little Richard]

Yup. Another 130.00. I'm just curious if it is bad. Is there something that ruining them. And why can't I get a voltage reading with DVA from trigger sensor wires to ground. Screen just shuts off. When I get some more time I'll mess with it and post any new findings.

 

[Bosunsmate]

You might want to check theres no leak from your +ve battery cable to engine crankcase ground such as a crack in solenoid housing or a short in the control box.
This you probably will of done but check powerpacks ground connection is clean, a bad one there can ruin them

 

[Little Richard]

Will do. Thanks for the help

 

[Little Richard]

Do y'all think I'm getting inductive kickback off coil(s) and it's toasting the scr in power pack. Maybe why my voltmeter goes blank when trying to test DVA off trigger to ground. Also is it ok to disconnect coil packs from power pack and then trying to test trigger or does it need a load resistor on it. Just don't want to damage anything else. Really don't want to replace whole ignition system but also don't want a bad part destroying another and vise versa. That could get real expensive