1989 Evinrude 70hp weak water stream

Ilwalker

Cadet
Joined
Jun 23, 2020
Messages
7
I have a 1989 evinrude tracker 70 hp that quit peeing at idle and weak stream at open throttle. The impeller and thermostat have both been replaced. Any suggestions?
 
Joined
Jan 17, 2019
Messages
946
most didn't get taken in for the cooling mods. is the telltale nipple at the top of the block on the exhaust? what temperature are you getting at #1 cylinder? Air would get trapped in them, and cause hotspots hence the service bulletin. do a search for the bulletin, #2276. the water pump upgrade included a grommet for the water hose as well.
 

Ilwalker

Cadet
Joined
Jun 23, 2020
Messages
7
most didn't get taken in for the cooling mods. is the telltale nipple at the top of the block on the exhaust? what temperature are you getting at #1 cylinder? Air would get trapped in them, and cause hotspots hence the service bulletin. do a search for the bulletin, #2276. the water pump upgrade included a grommet for the water hose as well.

Not sure how do you check the temp on the cylinders?
 

valvebounce

Petty Officer 2nd Class
Joined
Mar 18, 2014
Messages
102
If you are testing it in a tank/drum,the water pump needs to be below the waterline to purge the air out and for it to prime.
If you are using muffs,it won't prime properly.
 
Joined
Jan 17, 2019
Messages
946
i wouldn't worry about anything unless it's overheating on the boat in water, but is the telltale elbow at the bottom or top? try sticking a paperclip in the cooling nipple... sometimes gets clogged. you can blow into it with compressed air if it seems clogged as well.
 

Ilwalker

Cadet
Joined
Jun 23, 2020
Messages
7
i wouldn't worry about anything unless it's overheating on the boat in water, but is the telltale elbow at the bottom or top? try sticking a paperclip in the cooling nipple... sometimes gets clogged. you can blow into it with compressed air if it seems clogged as well.

What do you mean by telltale?
 
Joined
Jan 17, 2019
Messages
946
So just monitor the motor and you want to avoid surfacing the lower unit if you can help it without doing the cooling mod. if you get an IR temp gun, the temp at idle should be 125-155 degrees. I took a pic of the bulletin for you and its below. It's an easy and satisfying sunday afternoon job. don't worry too much about getting metal shavings in the exhaust area, but i recommend a vaccum cleaner and going slowly to suck up as many chips as you can, and of course greasing the drill bit as instructed.
 

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Ilwalker

Cadet
Joined
Jun 23, 2020
Messages
7
So just monitor the motor and you want to avoid surfacing the lower unit if you can help it without doing the cooling mod. if you get an IR temp gun, the temp at idle should be 125-155 degrees. I took a pic of the bulletin for you and its below. It's an easy and satisfying sunday afternoon job. don't worry too much about getting metal shavings in the exhaust area, but i recommend a vaccum cleaner and going slowly to suck up as many chips as you can, and of course greasing the drill bit as instructed.

Thanks!
 

Ilwalker

Cadet
Joined
Jun 23, 2020
Messages
7
So just monitor the motor and you want to avoid surfacing the lower unit if you can help it without doing the cooling mod. if you get an IR temp gun, the temp at idle should be 125-155 degrees. I took a pic of the bulletin for you and its below. It's an easy and satisfying sunday afternoon job. don't worry too much about getting metal shavings in the exhaust area, but i recommend a vaccum cleaner and going slowly to suck up as many chips as you can, and of course greasing the drill bit as instructed.

Here’s a video of it running
 
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