Evinrude 70773S: What is this part?

Have a question about your motor? All motor talk and questions go here.
Post Reply
acolic
Posts: 84
Joined: 24 Jun 2013, 09:37

Evinrude 70773S: What is this part?

Post by acolic » 08 Aug 2016, 20:02

Hi,

I have a new boat that has an Evinrude 1970 7077S3 70HP 2 stroke motor.

While I'm searching for a manual perhaps someone can tell me what this part does and what each position 1-12 indicates.

Thanks for the help,

Alex
Attachments
IMG_20160805_202626.jpg

Xtremeboats
User avatar
kofkorn
Donor
Posts: 528
Joined: 13 Oct 2011, 10:18
Location: Central MA

Evinrude 70773S: What is this part?

Post by kofkorn » 09 Aug 2016, 08:48

Based on your model number, that should be a 1977 70hp Johnson motor. Johnson didn't make a 70hp in 1970. That part is your power pack. It takes the charge from the alternator and takes the timing from the timer base and sends a electrical charge to the coil at the correct time for ignition of each cylinder.

Basic rundown of positions

1) Output to cylinder 1 coil
2) Output to cylinder 2 coil
3) Output to cylinder 3 coil
4) Connection to Stator
5) Connection to Stator
6) Kill wire from ignition (grounding this wire stops output to coils)
7)
8 ) Input from Timer base Position #1 (triggers Output to coil #1)
9) Input from Timer base Position #2 (triggers Output to coil #2)
10) Input from Timer base Position #3 (triggers Output to coil #3)
11) Connection from Timer base
12) Ground

Good luck!

acolic
Posts: 84
Joined: 24 Jun 2013, 09:37

Evinrude 70773S: What is this part?

Post by acolic » 09 Aug 2016, 13:01

Thanks a lot,

if I was wiring a voltmeter from the dash to the motor would I wire the positive to pin 6?

That way the voltmeter only works while the engine is on?

Thanks for the help,

Alex

User avatar
kofkorn
Donor
Posts: 528
Joined: 13 Oct 2011, 10:18
Location: Central MA

Evinrude 70773S: What is this part?

Post by kofkorn » 09 Aug 2016, 13:48

Don't wire it to #6, you'd never get your engine to start :) You wouldn't want to use any of the connections on your power pack for the voltmeter, none would give you an accurate battery voltage.

To use a volt meter the way you describe, you should attach the positive to the switched power from your ignition switch. This is the purple wire coming off of the big red plug. This one will have no power when your ignition is switched off.

You'll have to decide if it's easier to access this directly at the switch, or run it back from the motor.

Good luck!

acolic
Posts: 84
Joined: 24 Jun 2013, 09:37

Evinrude 70773S: What is this part?

Post by acolic » 10 Aug 2016, 16:33

Thanks,

are there any other connection on the motor that should have a gauge run to it for monitoring purposes?

Tachometer, water pressure gauge? etc?

While I'm rewiring the electrical I'd rather do it once.

Thanks for the help,

Alex

User avatar
Pappy
Donor
Posts: 2720
Joined: 15 May 2010, 00:38
Location: Central Florida

Evinrude 70773S: What is this part?

Post by Pappy » 10 Aug 2016, 18:41

The wires you are looking for are already run to the control box. Gray lead is your tach. lead.
Water pressure does have to be run, via a hose, directly from a port on the engine. There is no electrical sender on the engine for that.

Post Reply