1973 Evinrude Wont Stay Running

[chazmonro]

Is a Marine Starting battery with 600 cca/780 mca/120 rc big enough for this motor?

Using this battery, I can get the motor to start with the warm up leve in the up position and a little choak. She pops right off and seems to run really well for maybe 10-15 seconds or so and then dies. My gut is fuel pump, but I don't know enough to be sure. I was hoping some of you might have more insight.

Thanks,
Chuck

 

[oldboat1]

What motor? Post a model number.

 

[chazmonro]

50373r evinrude. Sorry.

 

[Bosunsmate]

Try using prime bulb as a manual pump while its running, if that rectifies the issue then yes you are right its the pump

 

[oldboat1]

(600 cca should be fine for starting.)

[Edit. Some info on fuel pump diaphragms here: https://maxrules.com/fixomc-std-pump-kits.php ]

 

[chazmonro]

So I replaced the fuel pump and it started ok, but again only would run for a few seconds at best. I manually used the choak and the throttle and I got it to run a bit better, but had to keep increasing the throttle to keep it going, and eventually it would just die out. I've ordered kits to rebuild the carbs. Should I replace all the fuel line?

 

[oldboat1]

Check compression, and measure spark.

 

[chazmonro]

Ok, both cylinders are showing 120 on compression, but after a bit of trial and error I did find the top coil was bad. So I'm waiting for that. I'm also going to rebuild both carbs. Anyone have any directions on doing the impeller on this thing? I am not sure how it all comes apart.

 

[racerone]

Removing the starter motor makes it easier to find the pin at the top of the shift rod.----That pin must be removed.to drop the lower unit.----Do not loose the pin as they are proud of it.---Big $ item

 

[chazmonro]

Ok, she runs. New cool pack and some carb adjustment and she purrs. Hey quick question. I replaced the impeller, how do I know it's working, where does the water from the pump come out on this old engine?

 

[oldboat1]

Most of the exhaust/water exits through the prop hub, but look for an exhaust relief cover just under the powerhead on the rear of the leg. When the leg is full of water — as it will be in the lake or in a test barrel — there should be a spray back there. While looking, though, make sure it’s not overheating as that’s the main thing. If the top of the head is too hot to touch, the motor is running too hot.

 

[chazmonro]

I can touch it and hold my hand there, I've just never done any of this before so I get nervous about getting out on a lake and having a catastrophic failure because I did something wrong. I think it's working the way it should though, thanks for all the help.

 

[boobie]

What's a " cool pack" ??

 

[racerone]

Water pump kit that came in a " pack " age I think.

 

[chazmonro]

Coil not cool.

 

[boobie]

Good thinking racer ???