Newbie Needs Help 76 Evinrude 70hp

[bipolarnut]

Hey guys. I'm new and need help. I have a 76 70hp Evinrude and it is giving me fits. It runs fine in a barrel. Starts fine but every time I take it out it gives me trouble. It seems to run fine on take off but after running for a little bit it starts cuttin out. Every time I take it to my mechanic it comes back doing the same thing. He is old and doesn't getr it out in the water. I thought it sounds like it is "hunting" but I think it may be cutting out. I went through 12 gallons of gas in only a couple of hours. It would run fine at times (25mph according to GPS) and at others only about (4mph). The fuel is going somewhere. This may sound weird but when I make my first turn on an outing it starts acting up and then I can never get it right no matter how I turned the boat. My children and I got stranded in the middle of a big Louisiana lake and I don't want to go through that again. Any ideas. Oh BTW My mechanic has relplaced the Powerpack and the coil.

Rev. Richard J. Scoggins, Jr.
Romans 8:28

 

[tashasdaddy]

Re: Newbie Needs Help 76 Evinrude 70hp

it sure sounds like some testing needs to be done on the water, did he replace all 3 coils? is it running hot? can you hold your hand on the top of the head for a 3 count with out burning? have you check spark, on all 3, when it is acting up. have you tried pumping the primer fuel blub to see if it will pick up.? lets start with these questions, and go from there.

 

[bipolarnut]

Re: Newbie Needs Help 76 Evinrude 70hp

First thanks for helping. Next, I am not sure about all three coils. I don't think he did and getting in touch with him is difficult now. Is there away to test them. All three cylinders are firing, although I am not sure if they are firing when acting up. Hopefully I will get to run today. The only question I can answer now is that the pumping the bulb has no effect.


BTW I work on small engines..i.e chainsaws and lawnmowers.. so I am a little familiar with ic but don't know much about boat motors.

Rich

 

[dschild]

Re: Newbie Needs Help 76 Evinrude 70hp

Try running the motor in your tank in the dark. Look at the coils. Do you see sparks?

 

[wavrider]

Re: Newbie Needs Help 76 Evinrude 70hp

YOu will use roughly 7 gals of gas an hour if you are running wide open throttle. 10% of your hp rating is the normal usage of fuel. At cruising speeds or slower you will use less of course

spark tester available at any auto store is around 8$, need this to test for good spark.

compression tester is around $3o for a low end one and will let you know what type of compression you have on the cylinders.

here is a link to check for ignition trouble shoting

http://www.boatpartstore.com/tips.asp

just follow the links to your engine type

 

[bipolarnut]

Re: Newbie Needs Help 76 Evinrude 70hp

Well I still haven't put it in the water but I did a little checking out. I hope to try it out tomorrow. I ran it here at the house but could not get it to malfunction. It started up great and ran like a champ. I have fire on all three cylinders as I said before. I undid each one and noticed a considerable change with the subtraction of a cylinder. My brother brought home a tach and compression tester from where we work and here is what we found. 125 lbs on all three cylinders and right at 5000 rpms. I did notice one thing that I had not noticed before as I pumped the bulb i noticed fuel leaking by where the fuel line plugs into the motor. It pulsed as I pumped the bulb. The hose clamp on the inside of the fitting was loose. Could this be the culprit? Could it be sucking to much air and not enough fuel? I know I won't really know anything until I put it under a load but I just thought I would update those of you who are helping me. BTW I did run it in the dark and saw no sparks. I'll keep you guys updated. Again thanks for the help.

 

[bipolarnut]

Re: Newbie Needs Help 76 Evinrude 70hp

Update. I just got in from running the boat and it performed well at first. It ran real strong and I thought removing the zip ties from my wires and throttle cables had fixed it but it started acting up my brother had my other boat out on the lake with us. We checked the spark and we had no spark on the top cylinder at first then intermitent spark after that. I am ordering another coil just in case but I wanted to know if it could be something else and how could I check to see if it is something else.