1972 85 hp evinrude starflight will bog while under load help please......

[JOEjones31989]

Ok this is my first post here and trying to do this from my phone so hang with me lol. A few months ago I bought a 1972 evinrude 85 hp starflight. As soon as I got it I replaced the water pump. And spark plugs. Took it out it ran ok a few times. Then started to bog down under load. Did some looking and realized the fuel pump went bad so I replaced that. But it is still bogging down unless I keep it choked then it smoothes out. I have done a compression check that is good. I've took apart both carbs cleaned them out and put new gaskets on. I've ran seafoam,through it. But still same issue. Anyone have any pointers?

 

[racerone]

Remove flywheel.-----Remove stator and distributor cap.--------Inspect anti-reversing spring.--------Clean and set the points to 0.010".--------Clean rotor and distributor cap.----------Unthread plug wires and replace the wee rubber boots.--------Carefully re-assemble.-------Torque the flywheel .

 

[JOEjones31989]

Ok I'll have to look into that this evening when I get off work. And get those wee rubber boots ordered. I'll keep you updated thanks on the quick reply.

 

[hidef]

When you changed out the fuel pump did you replace the fuel lines? The old fuel lines are not capable of handling today's gasoline with ethanol in it. The ethanol will breakdown the rubber in the lines.

 

[JOEjones31989]

hidef i did not right away, due to money restraints atm. but after i had it out the second time i did replace the fuel lines as i was rebuilding the carbs.

 

[JOEjones31989]

so i just got home. and with my luck it is pouring right now. so i wont be able to do any work on the motor this evening. but as soon as im able to check/clean and re gap everything ill update everyone.

 

[JOEjones31989]

ok sorry took a few days to get back with yall, so i took the boat out saturday evening and sunday morning. well saturday evening everything was running amazing. untill i ran out of fuel and went to my back up tank as soon as i did she started to spit and sputter all over again. i didnt think nothing of it until the next morning when i went out and swapped back to my normal gas tank after i refueled. i am convinced that my buddys gas tank [my spare] has a bad bulb and is sucking in air causing me to run lean. i have another question about my motor though if anyone can help me. the boat is a 1972 champ 16 foot boat. {thats what the title calls the boat} it is a stick steer pretty narrow boat. with my 1972 evinrude 85 hp i was able to do 33 gps mph but after i put the dolphin fin on my motor it dropped down to 27mph....... i think both those numbers are pretty low for my boat size vs my motor size. and i cant seem to find any numbers on my prop to figure out what the pitch is or anything. anyone have any suggestions on that part or should i go to a different part of the forums and ask?

 

[emdsapmgr]

Your engine may be mounted too low on the transom. That would put the anti-ventilation plate well underwater when on plane. You'd see a lot of water spray if it was mounted to low. If you then added a fin on that engine, (already mounted too low) you would look to see if that fin is also dragging underwater, causing even more water spray. that can cause poor performance and bad fuel economy.

 

[JOEjones31989]

Ok I'll check into that. I did order me a tach meter for my boat since it didn't have one that,should be in by tuesday. As a rough estimate where should the anti-vent plate sit compared to the bottom of the transom?

 

[JOEjones31989]

so i checked to see where the anti ventilation plate was in comparison to the bottom of my transom. they are pretty much inline with each other. i was checking my prop for a number or some sort of information to see if maybe i have the wrong pitch prop on. but their is absolutely no stamped numbers on this prop. and i just got the boat a few months ago so i have no info on this prop. besides that it is a SS 3 blade prop.