Any suggestions?

rodknocker

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May 11, 2007
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I have an OLD Evinrude 65 hp 3 cyl. outboard that has some kind of problem in that when you start it up, it idles fine. But when you hit the gas, it bogs down, and will not plane out unless you fiddle w/ the choke. I have cleaned the carbs 3 times, my brother cleaned them twice, but we cannot figure it out. this motor is the one with the electric shift; no gear cable. I changed fuel supply lines--the hose with the pump up bulb on it, as well as the fuel tanks. Fuel pump, possibly????
 

Rich976usaf

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May 9, 2007
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Re: Any suggestions?

im new, but i think it could be fuel pump is not pumping enough, or a leaky line sucking air? possibly the high speed oriface.
 

rodknocker

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Re: Any suggestions?

cleaned as in completely disassembled all parts of them, including bowls and needle valves, the three pin holes in the throat of the carbs were opened with a wire from a wire brush, and the main tubes a orifices were sprayed out with carb cleaner. This was done until the carb cleaner would spray through without any blockage. The fuel lines still seem to be fine. They done leak noe fo they have any visible crack in them. About the only thing else I can think of would be the fuel pump. I did sit up for a WHILE--2 years w/out being run.
 

iwombat

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Re: Any suggestions?

You may have gotten lucky, but you should never chase jets with wires. You'll end up enlarging them. However, those particular jets would only effect your idle settings. I just wanted to make sure you didn't just squirt carb cleaner down the throat and call 'em cleaned.

When you squeeze the bulb, does it stay hard for very long?
 

iwombat

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Re: Any suggestions?

Another possibility is the float setting. If your floats are not adjusted properly it could just be starved for fuel at full throttle.
 

rodknocker

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Re: Any suggestions?

Thats the thing. Sometimes you can pump it up w/ 4-5 pumps, other times, its like trying to squeeze a baseball. But, no, it seems to stay hard until it starts bogging out.
 

iwombat

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Re: Any suggestions?

An air leak past the bulb, or a torn membrane in the fuel pump would cause the bulb to go soft after a little bit.

The other test is to pump the bulb while it's misbehaving. If that perks the motor up the fuel pump needs rebuilding. If not I'd say your problem is in the carbs, or perhaps timing. Although timing doesn't seem too likely if choking perks it back up.
 

rodknocker

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Re: Any suggestions?

Now, I did--like a numbnut--take the fuel pump apart to make sure it wasnt clogged up due to sitting. When I took the internal parts out, the biggest piece in there was coming apart a little. Kind of like unlayering a stack of paper; Not tearing length ways. Know what I mean??
 

iwombat

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Re: Any suggestions?

I sort of understand, although I'm not sure what fuel pump we're dealing with w/o a year. Anyway, I'd say you're due for a fuel pump rebuild at least. I'd be checking those floats in short order too though. If your floats cut off the fuel flow too early, it'll behave like it's running out of gas when you open it up.
 

rodknocker

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Re: Any suggestions?

Sort of taking layers off of the thickness of it. Like if it was 7 layers thick, then it would have came apart between the 3 and 4 layers. Not really tearing, but making two diaphrams out of one and they would only be half as thick. Would the floats have gotten moved out of adjustment just by taking out the float pin and setting it to the side?
 

iwombat

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Re: Any suggestions?

If you put in a rebuild kit (didn't say if you did) it comes with a new float needle and bushing. You may need to reset the float after replacing those. Even if you didn't, the float tab is designed to be easily bent for adjustment. Pretty simple to take it out of whack. Most of the time you'll bend it in and cause the carbs to overflow. But, it's certainly possible to bend it out. It's also possible your float needles are just sticking. Now, I'm not saying that floats are your problem, but it's certainly worth eliminating as a possibility.

If you can de-lam the seals in your fuel pump its time for a rebuild kit.
 

rodknocker

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Re: Any suggestions?

Its on a 1972 Chrysler boat, and the only #'s I can find on it are 427-98-787956 or 427-98-782956. This was engraved by someone other than the manufacturer.
 

iwombat

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Re: Any suggestions?

Have you looked on the powerhead for the welch plug? Its a quarter-sized silver disk, usually just fore of the flywheel. Should have the model number and serial number on it. The model number will tell you what year it is.

Make that just aft of the flywheel - what was I thinking?
 
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rodknocker

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May 11, 2007
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Re: Any suggestions?

I didnt rebuild them, just took apart and cleaned. I guy I talked to today said that Evinrude only made this type motor--electric shift--for 1 or 2 years due to the problems w/ the shifting.
 

iwombat

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Re: Any suggestions?

Okay, I totally missed the electric shift tidbit. That's a '69-'72 I think - not sure. I think you can use a later model rebuild kit for the gaskets and membrane on that pump, but some of the little plastic doodads and springs you'll have to reuse. Either that or you can get a new later model fuel pump, but that's gonna be more spendy.

I'm sure someone else here knows for sure.
 
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