Funky Evinrude Problem at WOT

[radhorn]

Hello, I am new to this so forgive me if I ramble a bit.<br /><br />I have a 1978 35 hp Evinrude 2 stroke that I have had out 4 times. Its starts like a charm (electric start), idles solid and ran fine at WOT until the time before last I had it out. I was using the gas can that came with the boat that was very old. I had emptied the odl gas and replaced it. That day we put the boat in, it started right up, and off we went fishing. She ran great and fast like it had the previous times I ran it. After fishing that spot, we start it up and take off, but it will not open up at WOT. Only about 1/3 of top speed I’d say. We cuss. It will rev up in idle to what sounds like full throttle, but once in gear, it’s putput city. Weird thing is the third time we started it, we were going along slowly with it at WOT when it jumped, went back, jumped, went back and wham, it was back to full speed at full throttle. We rejoiced. We fished. We started it again and it was back to the 1/3 speed at WOT. Had it out again last Friday and it only jumped once, but never got back to full speed the rest of the trip. It also seems to run at full RPMs in reverse. My outings have been about 1 week apart and I bought the boat in May.<br /><br />I don’t know if this is relevant or not, but when it all started, my buddy started it and rammed it into forward at a very high idle speed. I hope it is nothing gear related.<br /> <br />Here is a list of what I tried that had no effect<br /><br />Adjusting the air intake from one extreme to the other even removed cap<br />Ran all of the gas out of it<br />Changed out gas tank<br />Gas line is new<br />Checked fuel filter, looks good and clean<br />Checked spark plugs, don’t look fowled<br /><br />When I replaced the old gas tank, I noticed some flaky junk left in the can from the old gas tank. Could that have clogged something in the motor if sucked up through the gas line?<br /><br />Any suggestions or help you can give would be greatly appreciated

 

[catfish1]

Re: Funky Evinrude Problem at WOT

sounds like a good carb cleaning would fix it, i think you have something floating around and clogging the jet.

 

[radhorn]

Re: Funky Evinrude Problem at WOT

Thanks for your response catfish. I think I will try using a spray or foam carb cleaner and if that don't get her going, then I'll look into pulling it. This motor had $500 of work done on it right before I bought it, so I think this is probably a chunk of old gas or something.<br /><br />My mom is from West Virginia. I love it up there.

 

[OBJ]

Re: Funky Evinrude Problem at WOT

Yellacat....look on the fuel pump and you will see a black round cover with a thumb srew. Behind the cover is a fine mesh screen that should filter the gas as it comes from the tank. Make sure this screen is clean. If the screen is missing, you will need to pull the carbs and clean out the bowls. If there is junk floating around in the bowls, spary carb cleaner will not help.<br /><br />Keep us posted....Thanks.

 

[radhorn]

Re: Funky Evinrude Problem at WOT

OutboardJim, thanks for your response. I pulled that screw and inspected the screen. It appeared to be in good order and was clean. So, do I have a chance with the spray or foam cleaner, or does it sound like something else?

 

[OBJ]

Re: Funky Evinrude Problem at WOT

Hi yellacat...<br /><br />No....I don't think the foam cleaner will help much. I'm tending to agree with catfish that a good carb cleaning and rebuild would be the way to start. But....before you do that, get some compression readings on the cylinders and check that you have good spark on each cylinder. You engine spark should jump a 7/16inch gap (don't know what that is in mm) with a hot blue spark. If compression is good and you got good spark, go for the carbs.<br /><br />Gotta' manual? If not, I would get one. They do help.

 

[tad7777]

Re: Funky Evinrude Problem at WOT

hello it sounds like a carb problem to me,, you need to take it in to a repair shop,unless you are able to take it aprt clean everything ,rebuild it,,i rebuild kit is only around 10- 20- dollars that should fix the problem Tad

 

[catfish1]

Re: Funky Evinrude Problem at WOT

yellacat, outboard jim is right. the spray foam wont do a thing! i think what you have is a small piece of something floating around and occasionally clogging the jet. (it doesnt take much!) if it were mine i would just take the carbs off & apart and clean with carb cleaner, spray the carb cleaner in all the holes to force any debris out. get yourself a manual, it will pay for itself many times over! let us know how it turns out

 

[radhorn]

Re: Funky Evinrude Problem at WOT

Thanks for all of your responses fellas. I took it out this weekend and changed the spark plugs and ran the Carb cleaner through it. tried all of this before I saw that ya'll thought the cleaner wouldn't work <br /><br />It went something like this...<br /><br />We backed the boat off the trailor. Took it out and it opened right up before I did anything to it. I says "well heck ain't that something". I ran the carb cleaner through it and waddaya know, back the old 1/3 speed at full throttle. We changes plugs, nothin. We run more carb cleaner, nothin'except for a few quick lurches while I ran it. Well I left it for about an hour and decided to get it out to take it home. I start it up and wham it runs full speed. I'm thinkin' the carb cleaner either got it finally, the carb is still clogged or it something electrical.<br /><br />Thanks for all of your responses again.

 

[catfish1]

Re: Funky Evinrude Problem at WOT

yellacat, its not a good idea to run carb cleaner through the engine while running it, what happens is it takes the oil off everything it contacts (no oil, no lubrication). i'm glad to hear that it was running full throttle again, but i'd bet it will act up again next time out.

 

[Sal G]

Re: Funky Evinrude Problem at WOT

Check to see if all the plugs are burning the same.<br />If one looks "cleaner" thn the others you may be getting water in that cylinder whickh will basically make your engine run -1 cylinder.<br />If thats the case, you need to replace your head gasket immediately. Check your compression.<br />Best of luck

 

[Sal G]

Re: Funky Evinrude Problem at WOT

Also forgot to mention.<br />If water is in cylinder- examine the head gasket<br />to see where it is faulty (if so). What caused the <br />gasket to fail?(if so)

 

[radhorn]

Re: Funky Evinrude Problem at WOT

Ok. Been a while, but I finally got to look at my boat and mess with it for an extended period of time.<br /><br />It turns out my problem is that the top cylinder is not getting any fire when the motor cuts back. The plugs are relatively clean.<br /><br /> I checked the connection with a meter from the power pack to the end of the spark plug wire and got a good connection for the bottom cylinder and nothing to the top. I then check the connection on the top cylinder from the power pack to before the little black thingy mounted to the cylinder that connects to the power pack on one side and the spark plug wire on the other. The connection is fine up to the thingy then it is gone after the thingy.<br /><br />(Can someone tell me what this thingy is and does? Is it a switch or should the connection be continuous through it all the time)<br /><br />I hypothesize that the thingy is either a switch, has short or is a switch with a short. <br /><br />I am tempted to replace it and see if it fixes my problem.<br /><br />Any thoughts?

 

[Walker]

Re: Funky Evinrude Problem at WOT

Coil????? Since it seems to be firing sometimes I'd pull that coil off and clean the ground strap and the head where it bolts on. Put it back together and give it a try.

 

[radhorn]

Re: Funky Evinrude Problem at WOT

rrrrrrr <br /><br />Replaced ignition coil to top cylinder. Did not fix problem. It is definately running on one cylinder. The top one cuts in and out. There is no spark to the top cylinder most of the time. It tends to do fine when you first start it, and then the top cylinder cuts out. The top cylinder will periodically cut in for short bursts, or sometimes for a few minutes and then it will go back to one.<br /><br />It sure sounds electrical to me. Anybody have any feel for what I might be facing? Could it be the power pack? or something before that?<br /><br />Any help would be greatly appreciated. <br /><br />The plugs seems to be in good shape and do not appear to be gunked up.

 

[Knightgang]

Re: Funky Evinrude Problem at WOT

You said that you replaced the coil. Did it come with the spark plug cap and boot on it? I have a Suzuki outboard and the coils do not come with the caps and boots, just the coil withe the primary lead and the plug wire. My caps screw into the end of the plug wire to make connection. It uses resistor spark plug caps. I had a spark plug cap go bad on my Suzi DT115. It did just what you are describing. I did the carbs first with no change (although I am an advocate of cleaning carbs). I have new spark plug caps on the way to me know. Can't wait to get back on the water.<br /><br />Try taking of your spark plug caps (if you can) and meter your coils that way. It will at least tell you if the coil and plug wire are any good.<br /><br />Knightgang

 

[radhorn]

Re: Funky Evinrude Problem at WOT

Knightgang, thanks for the response. <br /><br />No wires or caps were included with the coil. I’m not sure what the cap is though. If it is the point where the plug wire connects to coil, then that was part of the coil. I have switched the plug wire from bottom to top and the wire ran the good cylinder fine. The lead comes into the coil comes from the power pack though a plug adaptor.<br /><br />Probably wouldn’t hurt to replace the plug wires anyway though.