1985 evinrude 30hp (With video again!)

[ohmybad]

Once you watch the video you can tell that the motor will rev up and then I guess "sneeze" and sometimes die but usually keeps running. What can cause this, what can I check for? I really want to fish this weekend.

Thanks

Movie:
http://www.floridacoasts.com/motor.MOV

 

[mikesea]

Re: 1985 evinrude 30hp (With video again!)

Is the timer base(sometimes magneto plate )the flywheel operating ,does it rotate when you throttle,are the linkages connected to it ok.Is there a roller on top of the carb that rides on a cam type device on the plate I speak about.If so,does it look like there is anything worn off,like a plastic sleeve.If the roller is there ,while the engine is running,kinda help the roller to come out a bit,so if something was worn you could make up for it and see if the eng. runs better. Next,does that carb have needle valves that are adjustable.If so did you adjust by the book.Almost sounds like it could be leaning out. If thats a top needle I see,is it about 1 and a half turns out. I could be wrong on the turns but thats a number I remember from a long time ago. Either way try opening it .I think your problem is in the synconization,betyween the timer base or the carb.The carb could be adjustments.Also be sure the manual choke(redknob)isn't open

 

[iwombat]

Re: 1985 evinrude 30hp (With video again!)

Video really helps. With your discription I'd be inclined to say you've got a lean lag. But, I don't see any popping in the carb which I'd really expect to see if that was the case. Still, I'm used to spotting that on a four-stroke. Maybe two strokes pop in the exhaust. (Opinions?)

Have you done a spark check?

I'm inclined to think you've either got a clogged high-speed jet (if it is a lean-lag), or an ignition component on its way out.

 

[iwombat]

Re: 1985 evinrude 30hp (With video again!)

Thinking about it a little more. The sneezing is happening at about the point where the ignition system is under the most stress. You really ought to do a proper spark check.

 

[ohmybad]

Re: 1985 evinrude 30hp (With video again!)

Today I tried some carb cleaner while it was running and after I spray it the motor would run smooth and then go back to normal. Could this happen because it is not getting enough fuel and the carb cleaner is acting as fuel?

 

[iwombat]

Re: 1985 evinrude 30hp (With video again!)

Not likely. Carb cleaner is less combustable than gas. It's more likely that you're changing conditions in the combustion chamber enough so that the ignition system doesn't have to work as hard to jump the spark.

I'd really suggest a proper spark test at this point.

 

[iwombat]

Re: 1985 evinrude 30hp (With video again!)

FWIW spraying carb cleaner into the carb isn't very effective. If it is a carb problem you really need to disassemble and clean out all the passages individually.

Sorry, but it's true. I'd still start with the spark test and at least rule it out right away.

 

[OBJ]

Re: 1985 evinrude 30hp (With video again!)

Turn the low speed needle out about a half turn and see if that helps. Just sounds like a lean cough.

Once in the water, you'll likely have to readjust the low speed needle. To get it closer before launching, run the engine in a garbage can or drum.

 

[ohmybad]

Re: 1985 evinrude 30hp (With video again!)

Currently I have taken the carb off and completly cleaned it, also I checked every fuel hose and the fuel pump which all appear to be fine with no obstructions. The idle screw is doing nothing, could this be my problem?

 

[G DANE]

Re: 1985 evinrude 30hp (With video again!)

When you cleaned the carb, did you pay special attention th the small holes just above throttle butterfly inside carb throat, and did you have the low speed needle out while cleaning. Did the small keyholeshaped siliconegasket get right in place afterwards around low speed needle ?? turn needle all the way in, and seat it gently, no force. Then 1 3/4 turns out from buttom. It should run there. Rest of adjustment is in water, in forward gear, pulling boat. Sounds like lean sneezing to me. If turning low speed needle out soesnt affect if, either the mentioned small gasket is missing, or something is blocked.

 

[steelespike]

Re: 1985 evinrude 30hp (With video again!)

I wasn't able to play the video but the sneeze usually indicates a lean condition.Have you tried a little touch of choke to see if added fuel helps?Disconnect the gas line at the carb put it in a can carefully crank the motor with the kill switch closed and observe the the gas flow
should be a strong steady pulse.If good then check the delivery at the carb.Be sure the float valve is operating smoothly and float is adjusted properly and of course all passages and jets are clean.

 

[Fishstick1962]

Re: 1985 evinrude 30hp (With video again!)

Had a car motor once that did the same thing... the idle mix screw had no effect on engine. Found aluminum foil had been used to make a base gasket (jet mechs did this) and was leaking, replaced with new gasket, adjusted and it idled perfect. Just a thought...

G-Luck!

 

[ohmybad]

Re: 1985 evinrude 30hp (With video again!)

When I was cranking it today the starter came loose so I figured I didnt tighten the bracket enough so I checked the boilts and it turns out the screw hole got stripped from the force of the stater cranking and now I cant use the electric start. Whats the best way to fix stripped screw holes?

 

[mikesea]

Re: 1985 evinrude 30hp (With video again!)

That happens alot with those starters.Many people use the helicoil.But the best is ti have a guy weld it up ,and retap it like new.With the helicoil,your drilling a larger hole,which further weakens the casting.You could try it first.Be sure to use lots of locktite,and dont do a superman when tightening