Need help with Craigslist "Gem" 70hp Evinrude bogs over half throttle..

[Skifferskipper]

This is the second boat ive bought off CL and the second time ive been trying to fix a faulty outboard.. Heres the scoop.. I Put it in the water and started it.. Started easy so far so good.. Idled it for a bit it was a bit smokey but old engine. Got it out and started cruising speed and that was good.. Put the throttle down to wide open you can hear the engine wanted to go but the power was nil this is a learning curve for me and im not sure what to try next. I dont really know boats but Im pretty decent with car engines.. Can anyone help me..

 

[Skifferskipper]

Re: Need help with Craigslist "Gem" 70hp Evinrude bogs over half throttle..

This is the second boat ive bought off CL and the second time ive been trying to fix a faulty outboard.. Heres the scoop.. I Put it in the water and started it.. Started easy so far so good.. Idled it for a bit it was a bit smokey but old engine. Got it out and started cruising speed and that was good.. Put the throttle down to wide open you can hear the engine wanted to go but the power was nil this is a learning curve for me and im not sure what to try next. I dont really know boats but Im pretty decent with car engines.. Can anyone help me.. It is a 1974 70hp evinrude with 3carbs (Someone told me that was the newer style of this model..

asd

 

[Monte1961]

Re: Need help with Craigslist "Gem" 70hp Evinrude bogs over half throttle..

Can u give us the exact model?

 

[wilde1j]

Re: Need help with Craigslist "Gem" 70hp Evinrude bogs over half throttle..

Next time you buy a motor, test it on the water at full power. Only way to know what you're getting.

 

[Skifferskipper]

Re: Need help with Craigslist "Gem" 70hp Evinrude bogs over half throttle..

Yes sir.. Its a 70473-m I Was told it was a 1974 Evinrude 70hp

Jim- Yes sr Lesson learned..

 

[Daviet]

Re: Need help with Craigslist "Gem" 70hp Evinrude bogs over half throttle..

Yes, it's a 1974 70hp.
I would start with some basic checks, compression, spark and fuel delivery. Those engines will idle pretty good on two cylinders. It might be time to overhaul the carbs, could have some high speed jets restricted.

 

[Skifferskipper]

Re: Need help with Craigslist "Gem" 70hp Evinrude bogs over half throttle..

I Checked the compression, It was high 90ish all the way down I Checked the lines with a spark tester seems good.. Its got a nice blue spark when I arc aganst the block.. However I Just was doing some work on this motor and found that the screw in the bottom of the carb on the number three or lowest carb and cylinder (I Believe to be the plug for the float bowl or some kind of something or other for the highspeed jet correct me if im wrong) Was stripped out and finger tight and im assuming that may have been the problem so i just helicoilded it and it seams to have seated.. I Believe I may have found my problem however I cant test the *At a load* Setting on my motor in a barrel unfortunatly so I have to take it and drop it back in the lake tomorrow and see what happens.. I Also pulled the spark plugs that I had replace a couple weeks ago and they all seemed pretty clean just seemed like they had a little oily gas on them..

 

[Skifferskipper]

Re: Need help with Craigslist "Gem" 70hp Evinrude bogs over half throttle..

Oh and I Blew about a half a bottle of carb cleaner through it..

 

[Daviet]

Re: Need help with Craigslist "Gem" 70hp Evinrude bogs over half throttle..

The high speed jet sits behind that plug on the bottom of the bowl.

 

[Skifferskipper]

Re: Need help with Craigslist "Gem" 70hp Evinrude bogs over half throttle..

Do you know if there is some kind of torq spec to that Like if I screw it down to tight will it mess with the jet or anything inside the carb?

 

[Skifferskipper]

Re: Need help with Craigslist "Gem" 70hp Evinrude bogs over half throttle..

and another question, Ive heard about being able to clear it with a small peice of copper wire Can I do that by just taking this bolt out or do I need to remove the whole jet?

 

[Chinewalker]

Re: Need help with Craigslist "Gem" 70hp Evinrude bogs over half throttle..

When you blew that carb cleaner through it, were the carbs disassembled on the bench? If not, then you just wasted the carb cleaner. It doesn't do much to an assembled carb - gotta get them apart to properly clean them...

 

[Skifferskipper]

Re: Need help with Craigslist "Gem" 70hp Evinrude bogs over half throttle..

No I Had just found that bolt that was stripped and did enough research on it to figure out what it was Sprayed some carb cleaner gave it a couple minutes and then hit it with compressed air hoping to knock some goo loose. So with that plug missing im assuming the bottom carb was just acting as a paper weight and might function now.. So later today im going to drop it in the lake and see what happens.. Ill keep you posted..

 

[Scubaproh20]

Re: Need help with Craigslist "Gem" 70hp Evinrude bogs over half throttle..

Keep an eye on that compression if its been bogging and running lean it also leans out oil with the extra oil and fuel it might come back a bit or get worse quickly. since its near the bottom of the compression range it may be time to look for some rings and maybe seals.