1985 70hp Evinrude VRO question

danv1

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Aug 26, 2005
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The motor doesn't have the power it used to have. I tested the compression in all 3 cylinders, they were all in the 120's. I rebuilt the 3 carbs. But the motor just won't run properly. <br />When running, if I spray carb cleaner in the top carb it nearly stalls the engine, in the 2nd carb It doesn't affect it as much and in the bottom carb it barely affects it. It has blue spark on all 3 plugs. Any ideas what could be wrong?
 

Joe Reeves

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Feb 24, 2002
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Re: 1985 70hp Evinrude VRO question

Spraying carb cleaner in the carb throats does nothing really. Spray some pre-mixed fuel into the carb throats if you're going to spray anything.<br /><br />It sounds like you have overlooked something within the carburetors. Did you look at and manually clean the fixed brass high speed jets that are located in the bottom center portion of the float chambers?<br /><br />Besides soaking the float chamber in carburetor cleaner, manually clean those jets with a piece of mechanics wire (solid single strand steel wire).
 

OBJ

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Dec 27, 2002
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Re: 1985 70hp Evinrude VRO question

Hi Dan.<br /><br />Just saying an engine won't run properly isn't quite enough info. Here's some questions to think on.<br /><br />Is it hard to start?<br />Will it get on plane?<br />What do the plugs look like after running?<br />Does it get hot or does it stay cold at idle?<br />What do the fuel lines look like....softplyable or hard.<br />How old is the VRO pump?<br />When you cleaned the carbs, did you soak them and follow up with compressed air? Did you install new carb kits?<br />Are all the throttle plates opening at the same time as the control is advanced? <br />Will the spark at each cylinder jump a 1/2" gap?<br /><br />In short, just give us all the info you can think of that may give us a lead.<br /><br />And please don't use carb cleaner to shoot into the throats. Use premix gas in a spray bottle. No lube in the carb cleaner.<br /><br />Thanks.
 

danv1

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Re: 1985 70hp Evinrude VRO question

The carbs were rebuilt about a year and a half ago, I don't believe that they put new carb kits in them though, I think they just cleaned them out. I just ordered three carb kits so as soon as they arrive I'll do a complete soaking and rebuild on the carbs. <br /><br />The fuel lines are soft and aren't leaking anywhere. <br /><br />The engine starts fine<br /><br />It does plane out, but just takes longer to get there. It has a lot of trouble pulling a tube, since it takes longer to get on plane.<br /><br />I put in new NGK plugs and after a day or so of running they are black chunky and wet on the side with the electrode and the opposite side is clean(light brown)<br /><br />The VRO pump is probably the original, not sure though it was on the boat when I bought it. <br /><br />I'm going to pick up a spark tester as soon as I get back from vacation next week and let you know if the spark is jumping about 1/2"<br /><br />I'm not sure if the throttle plates are opening at the same time the throttle control is advanced.<br /><br />Thanks for the info and I'll get back with you guys next week as soon as I get back in the country.
 
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