1976 evindude 115 wont go fast, help please!!!!

Hey guys, new to this, looking for help before I send her to the shop, I got a 1976 evinrude 115 on a 16ft flat bottom aluminum boat and everything seems to be fine, its getting gas, pulled the carbs off and they were spotless, and gas was new, spark on all 4 cylinders, starts fine and runs fine in neutral, Revs fine in neutral and never misses a beat in neutral on miffs, but when I took it out to the river a while back when I put it in gear it wanted to die unless I put it in gear quick and when throttle was advanced all the way I topped out at about a 12-15 MPH and that's the fastest it would go but never stalled, just wouldn't go fast at all, my buddies 35hp go-devil was running circles around me, any advice would be greatly appreciated!!!!

Re: 1976 evindude 115 wont go fast, help please!!!!

check compression see of all cylinders are firing evenly

Re: 1976 evindude 115 wont go fast, help please!!!!

The engine may not be running on all 4 cyls. If you have any weak ignition components, they tend to fail (break down) once the engine heats up to normal operating temps. If you have an inductive timing light, you can do your own testing. When running, put the timing light lead on each spark plug wire to check the spark. The flashes from the gun will tell you if you have no spark, weak spark, intermittent-etc. Best to have the boat floating in the lake, and the engine idling in gear (under load) when you do the testing.

Re: 1976 evinrude 115 wont go fast, help please!!!!

Re: 1976 evinrude 115 wont go fast, help please!!!!

emdsapmgr said:

The engine may not be running on all 4 cyls. If you have any weak ignition components, they tend to fail (break down) once the engine heats up to normal operating temps. If you have an inductive timing light, you can do your own testing. When running, put the timing light lead on each spark plug wire to check the spark. The flashes from the gun will tell you if you have no spark, weak spark, intermittent-etc. Best to have the boat floating in the lake, and the engine idling in gear (under load) when you do the testing.

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Thanks For the reply I have my buddies at work what the problem could be and they said the timing advancement I have no idea were that could be but they also said that it could be the power pack I do not have a timing light nor have the money for one right now so I was looking for maybe a quick fix that I can do myself without having to take the boat to the lake, the guy I bought it from I put new coils in it but it has the original power pack, is there anyway I can check to see if it is the power pack?

Re: 1976 evinrude 115 wont go fast, help please!!!!

Re: 1976 evinrude 115 wont go fast, help please!!!!

You can rent a timing light at most auto parts stores which will do the job.

Re: 1976 evinrude 115 wont go fast, help please!!!!

Re: 1976 evinrude 115 wont go fast, help please!!!!

Your Buddies at work were maybe referring to the time base not advancing. Is it ??

Re: 1976 evinrude 115 wont go fast, help please!!!!

Re: 1976 evinrude 115 wont go fast, help please!!!!

boobie said:

Your Buddies at work were maybe referring to the time base not advancing. Is it ??

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Yes sir it is advancing, it just wont go fast, it revs up fine in neutral but when in gear it will not go above around 10-15 mph

Re: 1976 evinrude 115 wont go fast, help please!!!!

Re: 1976 evinrude 115 wont go fast, help please!!!!

Revving n neutral is totally meaningless. There is no load on it to hold it back. Your motor probably is not running on all 4 cylinders. It takes specialized equipment to test the powerpack, but you CAN check for spark. Rig up some sort of a spark gap from the plug wires to ground and crank it over. It should jump a 1/2" gap on all 4 wires with ease. If it will do that, the power pack is ok.

As for the timing, DO NOT go messing with it. It can't mysteriously change by itself. Your buddy may have been referring to the timing advance part of the throttle sticking. That is fairly common. As you advance the throttle, most of the initial movement should be the arm that rotates the timing plate. At full rotation of that plate, the carburetor throttles should then open wide.

Re: 1976 evinrude 115 wont go fast, help please!!!!

Re: 1976 evinrude 115 wont go fast, help please!!!!

Yes sir I know its meaningless but I don't have the equipment or knowledge to do all the tests and we checked the spark at my buddies duck house when the boat was actually in the water and we pull each spark plug wire and he held a screwdriver into the wite and held the shaft of the screwdriver away from the tip of the spark plug in the block to see if we could get spark and we got spark on all 4 cylinders, and as for the throttle sticking, I checked that today and the throttle is advancing the part under the flywheel but my neighbor said that that wasn't my problem and that it had to be something electrical because it was getting gas and that I should take it in to a marine place and let a qualified mechanic check it all over and check the timing and electrical and such, cause this is only my second boat and third motor and I'm tired of getting stranded when I.go out, I either get stranded because of motor related issues, I'm.batting 1000 on getting stranded because of motor issues and I can't have that come duck season LOL but I appreciate all halls help and will update when I find the source of the problem!! Thanks guys!!!

Re: 1976 evinrude 115 wont go fast, help please!!!!

Re: 1976 evinrude 115 wont go fast, help please!!!!

And What is is the compression on the cylinders?

Re: 1976 evinrude 115 wont go fast, help please!!!!

Re: 1976 evinrude 115 wont go fast, help please!!!!

Hey y'all finally got it running, turned out it was the carbs, I had a real eye opener to Carb jobs, apparently it's more than just cleaning jets and checking floats, as the mechanic told me, there's waaaaaaay more to it, but ya, just rebuilt carbs was all it needed and she's running wide open like a scalded ape, so thanks again for.all yalls help!!

Re: 1976 evinrude 115 wont go fast, help please!!!!

Re: 1976 evinrude 115 wont go fast, help please!!!!

Blast-N-Cast said:

Hey y'all finally got it running, turned out it was the carbs, I had a real eye opener to Carb jobs, apparently it's more than just cleaning jets and checking floats, as the mechanic told me, there's waaaaaaay more to it, but ya, just rebuilt carbs was all it needed and she's running wide open like a scalded ape, so thanks again for.all yalls help!!

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Glad the weather is nice enough for you to run a boat this time of year. Getting blasted with a snow storm right now. At least it's only the first one of the year and we are almost into March.