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1979 Evinrude 4hp not getting fuel

D

Dangit

New member
Hi all, newbie here to the forum. Tried to do a quick search for answers but didn’t find what I was looking for. I hope you will be able to help me out.
My Father gave me a 1979 Evinrude 4 hp outboard so that we can fish the hp restricted water near our homes. When I picked it up from him he asked I thought it would be an easy task to get it running. The tank smelled varnished but I thought “piece of cake, we’ll be on the water in no time”. That was 2 months ago!!!
Tearing engines apart to rebuild is nothing new to me, but I am not too familiar with outboards so this is what has occurred so far.
Checked for spark and compression. Good spark but no compression. Checked to ensure head wasn’t warped. Replaced head gasket. Pistons look good, but a little bit of side to side play in cylinder. Removed carb tore apart and found it was very clean and had no build up in it. Soaked in carb cleaner for two days, wiped down, blew out all passages and rebuilt with new carb kit. Set float height at level with carb body. Replaced needle and installed until just making contact and backed out 1.5 turns to start. Removed fuel tank from top and filled with carb cleaner. Let soak for 2 days. Emptied and rinsed with 50:1 mix gas. Ensured fuel shut off was working and that fuel was flowing. Replaced fuel lines with high pressure fuel line and replaced in-line fuel filter with clear version. Used marine zip ties where needed. Replaced both plugs with Champion L77JC4 plugs and gapped.030. Filled tank with 50:1 high octane, opened cap valve and proceeded to pull recoil 5 billion times with no success. Try removing cap completely to ensure tank is getting air, no luck. Out comes the ether, fires right up. I figured that it should definitely start now, Pull some more and nothing happens. Spray fuel into carb and runs fine. Pull fuel line, Fuel is getting to the carb but when I pull apart to inspect no fuel in bowl. Recheck all passages, no blockage found. Needle and seat are not binding. All jets clean. Reinstall and nothing but more pulling on recoil and cursing! Tap on carb body to see if needle is sticking, no luck.
Time to drink frosty beverages and figure out why I didn’t bring to professional mechanic from the start and still tell everyone I got it running, but alas I will not be deterred!
Any help would be greatly appreciated! Thanks for your time .
 
Dangit said:
Hi all, newbie here to the forum. Tried to do a quick search for answers but didn’t find what I was looking for. I hope you will be able to help me out.
My Father gave me a 1979 Evinrude 4 hp outboard so that we can fish the hp restricted water near our homes. When I picked it up from him he asked I thought it would be an easy task to get it running. The tank smelled varnished but I thought “piece of cake, we’ll be on the water in no time”. That was 2 months ago!!!
Tearing engines apart to rebuild is nothing new to me, but I am not too familiar with outboards so this is what has occurred so far.
Checked for spark and compression. Good spark but no compression. Checked to ensure head wasn’t warped. Replaced head gasket. Pistons look good, but a little bit of side to side play in cylinder. Removed carb tore apart and found it was very clean and had no build up in it. Soaked in carb cleaner for two days, wiped down, blew out all passages and rebuilt with new carb kit. Set float height at level with carb body. Replaced needle and installed until just making contact and backed out 1.5 turns to start. Removed fuel tank from top and filled with carb cleaner. Let soak for 2 days. Emptied and rinsed with 50:1 mix gas. Ensured fuel shut off was working and that fuel was flowing. Replaced fuel lines with high pressure fuel line and replaced in-line fuel filter with clear version. Used marine zip ties where needed. Replaced both plugs with Champion L77JC4 plugs and gapped.030. Filled tank with 50:1 high octane, opened cap valve and proceeded to pull recoil 5 billion times with no success. Try removing cap completely to ensure tank is getting air, no luck. Out comes the ether, fires right up. I figured that it should definitely start now, Pull some more and nothing happens. Spray fuel into carb and runs fine. Pull fuel line, Fuel is getting to the carb but when I pull apart to inspect no fuel in bowl. Recheck all passages, no blockage found. Needle and seat are not binding. All jets clean. Reinstall and nothing but more pulling on recoil and cursing! Tap on carb body to see if needle is sticking, no luck.
Time to drink frosty beverages and figure out why I didn’t bring to professional mechanic from the start and still tell everyone I got it running, but alas I will not be deterred!
Any help would be greatly appreciated! Thanks for your time .
Click to expand...

"Good spark but no compression" You have to get this solved first. Without compression it's not going to fire.
 
Fdrgator, I agree it seems like the needle is not opening to allow the fuel into the carb. But I double checked at least 3 times that the float was set level and that the needle operated smoothly. Just doesn’t make any sense to me. That is why I turned to this forum to see if anyone else has had an issue like this.
 
Revisit carburetor work.----Does spark jump a gap of 5/16" on both leads , yes or no ?
 
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If the fuel gets to the carburetor inlet fitting, but not into the carburetor, it simply has to be a matter of the float valve not allowing it to get in. Open the door and whatever wants to come will come in.
 
Dangit said:
Fdrgator, I agree it seems like the needle is not opening to allow the fuel into the carb. But I double checked at least 3 times that the float was set level and that the needle operated smoothly. Just doesn’t make any sense to me. That is why I turned to this forum to see if anyone else has had an issue like this.
Click to expand...

Have you aslo checked the float drop ? It should be 28 to 33 mm. See the diagram in the manual on the Boatinfo website.

Id expect the needle to be a soft tip one and for there to be a small clip between the needle and the float arm so that the needle is pulled off its seat when the float drops. Is that fitted.

Check that you can blow into the fuel inlet, through the needle valve and into the float chamber

Final thought. The float chamber vent is not blocked?. If that is blocked air cannot escape from the float chamber and fuel will then not be able to fill the bowl although it should flood the carb via the high speed nozzle
 
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Racerone, I did not measure the spark jump. The spark was very not a weak one. I will check this weekend. Thanks for the advice.
 
Vic’s-I did not check the float drop. I will this weekend when I check the spark gap. Yes the needle is attached to the float with the spring clip. I did try to blow into the fuel inlet on the carb, with my mouth only, no compressed air. (I had already blown out all vents/openings after soaking). I could not get air into the carb which still leads me to think it is the needle not allowing fuel into the carb. Hopefully when I check the float drop it will take care of the issue. All vents/openings in the carb where cleaned out and allowing carb cleaner to flow when sprayed into them. Thank you for your help. I will update after I work on it.
 
Dangit said:
Vic’s-I did not check the float drop. I will this weekend when I check the spark gap. Yes the needle is attached to the float with the spring clip. I did try to blow into the fuel inlet on the carb, with my mouth only, no compressed air. (I had already blown out all vents/openings after soaking). I could not get air into the carb which still leads me to think it is the needle not allowing fuel into the carb. Hopefully when I check the float drop it will take care of the issue. All vents/openings in the carb where cleaned out and allowing carb cleaner to flow when sprayed into them. Thank you for your help. I will update after I work on it.
Click to expand...

Absolutely. If you cannot bow through the inlet fuel wont get through either.

Not sure if it is likely or even possible but make sure you have not installed the float upside down
 
I want to thank everyone who replied to my post. I got it running top notch this evening! I had been thinking about what could possibly be wrong so I was able to check the spark gap jump and it was 5/16 plus! I tore the carb apart again and blew all passages out again. When I screwed the seat into the carb body, I noticed that it seemed like it was bottoming out. Tried to blow through fuel inlet and was unable to. Grabbed the old seat and I saved and decided to take measurements with micrometer they were both the same length. Then I realized that there must have been a nylon washer under it. Found the parts that weren’t used in the carb kit and there it was. I didn’t realize it was needed because it wasn’t there when I pulled it apart. It just goes to show you how sometimes you just have to slow down and make sure you double check everything! The outboard started on the third pull and the enrichment needle only needed to be adjusted to 1.75 turns out. Now I can’t wait to get it on the water.

thank you all again!
 
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