1981 evinrude 70 hp

[tina beat]

outside of water runs goods when put it in all it want to do is bog out.

 

[catchingmore]

Re: 1981 evinrude 70 hp

did you run it in a bucket are sime sourt of water tank

 

[tina beat]

Re: 1981 evinrude 70 hp

i put the muffs on it and ran it ran fine then put it in water and it want to bog out

 

[tina beat]

Re: 1981 evinrude 70 hp

i was told it was back prussure

 

[Silvertip]

Re: 1981 evinrude 70 hp

You were told correctly. Idle mixture and idle speed must always be adjusted with the engine in the water. There is no exhaust back pressure when running on muffs. Adjusting on muffs can get you in the ball park but final adjustments must be made in the water.

 

[tina beat]

Re: 1981 evinrude 70 hp

what sould i do about the back prussure i'am getting

 

[sloopy]

Re: 1981 evinrude 70 hp

start it in a higher throttle setting on the boat ramp. There is probably a button on the side of the throttle that allows you to increase the idle. Once you get the idle to where you want it go over to the engine and adjust the idle screws on the carb(s).

 

[tina beat]

Re: 1981 evinrude 70 hp

i thought back prussure had to do with the timing

 

[tina beat]

Re: 1981 evinrude 70 hp

i check my compression on it and the top one was getting about 20 the middle on was getting 60 and the third was getting 90. does anyone know how to take care of the bad compression.

 

[rickdb1boat]

Re: 1981 evinrude 70 hp

Rebuild....

 

[tina beat]

Re: 1981 evinrude 70 hp

it doesn't need rebuilt it just need to be ajusted. it start run good out of the water but water it run like crap

 

[tina beat]

Re: 1981 evinrude 70 hp

does anyone know how to ajust the timeing on a 70 hp evinrude it's a 1981.

 

[DJ]

Re: 1981 evinrude 70 hp

Manual,<br /><br />Your compression readings say that you have a nearly dead cylinder. Only a rebuild will fix that.

 

[tina beat]

Re: 1981 evinrude 70 hp

is there a way i can change my timeing to see if it will fix my prblem

 

[tina beat]

Re: 1981 evinrude 70 hp

i was told it was the back pressure from a guy the rebuild motor. but i don't know how to check the timing

 

[fireman57]

Re: 1981 evinrude 70 hp

As you were told by the guys that make a living working on these engines changing your timing will not fix this engine. You have bad compression which would lead to broken rings, scarred cylinders, hole in piston, or whatever. Pull the head and look for yourself and you will probably see what is going on. Check prices for a rebuild or check the price for a powerhead right on this site. If you still want to change your timing then do a search using the red search feature at the top of the page and you will find plenty of threads dealing with this. When you have a heart attack and the doctor tells you that you had a heart attack do you tell him that it is really just a cold?

 

[fireman57]

Re: 1981 evinrude 70 hp

Check for a sheared flywheel key. That should be the only reason that yur timing would be off.