70 Evinrude problems

fireman1146

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Joined
Mar 29, 2002
Messages
12
I've got a 1975 70 hp Evinrude. When i took the boat out the engine would run,but only with the warm up leaver up, then when I tried to throttle up it would die. I'm new to working on outboards, dont know much.Help!!
 
D

DJ

Guest
Re: 70 Evinrude problems

Fireman,<br /><br />We'd like to help. Give us a little history and engine info. Mod# Ser#, etc. The numbers will be located on the engine bracket that attaches to the boat. Usually on the left side, looking from rear.
 

fireman1146

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Joined
Mar 29, 2002
Messages
12
Re: 70 Evinrude problems

The model # is 70573F serial # J0015462. Had the boat a little over 1 year. Ran pretty good last year to me. Felt somewhat slugish on takeoff and takes a few min to plane out. The boat is a 12 ft. Norris Craft bass boat.
 

JB

Honorary Moderator Emeritus
Joined
Mar 25, 2001
Messages
45,907
Re: 70 Evinrude problems

Howdy, Fireman.<br /><br />There must be a misprint here. I read a 12 foot bass boat with a 70hp engine on it. That sounds more like a rocket sled than a bass boat. Even with only 2 cylinders firing it ought to jump out of the water when you open her up.<br /><br />Your symptoms are classical fuel starvation. <br /><br />Set us straight on the details of your boat and some history.<br /><br />Red sky at night. . .<br />JB :)
 

fireman1146

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Joined
Mar 29, 2002
Messages
12
Re: 70 Evinrude problems

Sorry, I went back and checked it agian. Its a 1975 16' Norris Craft with a 70 hp Evinrude outboard. The boat is rated up to an 80 hp. Sorry agian. Im still new to boating, about all I know about boats is how to fish out of them:) If there is anything else you need to know just ask.
 

fireman1146

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Joined
Mar 29, 2002
Messages
12
Re: 70 Evinrude problems

Dont know much history of the boat. Only had it a little over a year. It was my grandfathers, he baught it about two years ago and im left to get it ready this year and he is not around to tell me any history. sorry.
 

novacane

Seaman
Joined
Mar 8, 2002
Messages
70
Re: 70 Evinrude problems

sounds likes shes runnin lean garbage in the carb ill bet a parshall block of a main jet or air bleed rip off the top air horn of the carb clean it out real good bugs love to crawl thru these tunnels in your carb if it sits for some time ck float leval for get spec if it aint handy, rule of thumb that it be some what level,<br />comon sence thing, have fun, easy on runnin it till<br />its repair lean engine will lead to dead engine <br />youll fry it in a heartbeat
 

JB

Honorary Moderator Emeritus
Joined
Mar 25, 2001
Messages
45,907
Re: 70 Evinrude problems

Okay, Fireman, I have a better picture now.<br /><br />Your engine needs a complete physical exam.<br /><br />1. Get a service manual that covers it. Clymers has a good one for about $35. It is #B736.<br /><br />2. Run a compression check. All cylinders should compress 100psi or better and be withing 15psi of each other.<br /><br />3. Verify that you can get a 1/2 arc off of each plug wire. Install new plugs.<br /><br />4. Dismantle and clean the fuel pump and all three carbs. Replace any suspected valves, needles and diaphrams. You might want to go ahead and put overhaul kits in.<br /><br />5. Clean and inspect your complete fuel system: Tank cap, tank, pickup, connectors, hoses, primer bulb. No crud, blockage or leaks allowed.<br /><br />6. Check the Throttle/timing linkage and synchronization. Probably okay. Don't mess with it unless it is obviously off.<br /><br />Fresh, 87 octane fuel at 50:1 with TC-W3 oil. Muffs on and water flowing at least 30 sec. Crank her up and see what happens.<br /><br />Let us know.<br /><br />Red sky at night. . .<br />JB :)
 

fireman1146

Cadet
Joined
Mar 29, 2002
Messages
12
Re: 70 Evinrude problems

many thanks guys. Ill try that and let yall know when i get it fixed and how it does. :)
 

fireman1146

Cadet
Joined
Mar 29, 2002
Messages
12
Re: 70 Evinrude problems

thanks guys. It worked. Cleaned carbs and installed new plugs, throttle linkage ok. Have not taken her to the lake yet but she ran great on the muffs, no more idle problems. Hope to get to the lake later this week. Let yall know how she does in the water. Again many thanks. Know a little more now.
 
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