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Yamaha u5 1967ca. engine problems?

Yamaha u5 1967ca. engine problems? Topic: Crankcase seal
June 17, 2019 / By Damiana
Question: Whenever I am in 3rd gear and the engine has been on for more than 10 min, the engine starts to fail and It seems as if I am running out of gas and proceed to slow down back into 2nd gear from 35mph to 20 mph. While in 2nd gear everything seems great. until i spend more than a few seconds in 3rd and it starts all over again. It is gassed and oiled properly. Shoot me a couple ideas on how to fix this please :D much appreciated.
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Best Answers: Yamaha u5 1967ca. engine problems?

Blythe Blythe | 9 days ago
Possibilities in order of likelyhood: Bad crankcase seals or gasket. Common problem with older 2-strokes. Restricted fuel line or passages in carb allowing float bowl to empty faster than it can be replenished. This includes plugged fuel filter. Float level too low. Vapor lock on fuel tank. Try loosening the gas cap. Coil breaking down.
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Blythe Originally Answered: Having small engine/ go kart engine starting problems?
Perhaps you are having a compression issue? Pour oil into the cylinder(s) to temporarily restore compression. If after this it fires up, that's your problem. You could also have a problem with your mechanical timing. Check your engine to see if this is the case as well. But of course, it could be mostly anything. These are just some probable causes. Good luck!
Blythe Originally Answered: Having small engine/ go kart engine starting problems?
pick the flow adjustment or gas restrict. might desire to examine your gas transport, you state that is going to run positive then stall, sounds which you run the carb bowl out of gas speedier then the transport might desire to maintain up. examine for a restrict. stable success.
Blythe Originally Answered: Having small engine/ go kart engine starting problems?
Maybe this link would help: http://gokartbazaar.forumotion.com/t109-troubleshooting-your-go-kart-engine-idling-problems

Aiyana Aiyana
It may sound like the fuel petcock is plugged up and cause the fuel flow goes slow. Remove the gas tank. Then Remove the petcock from gas tank. There is a fuel filter on petcock may plugged up. clean it out and you may need to clean the gas tank. Second is possible the two stroke muffler start to clogged up. you need to burn up the muffler by torch the muffler body and blow with air compressor. let all the smokes and carbon out. or put in camp fire. please do not overheated the muffler, the metal will melt.
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Aiyana Originally Answered: Several minor problems with my car involving engine oil. Please HELP?
It sounds like the engine is "making oil". If you have not added oil since your last oil change, and you check it after running it for one day, or over a few days, then it is making oil. The piston rings are allowing gas into your crank case. If you have a carburetor, the gas is coming from there. If you have a fuel injected engine, one of the injectors are sticking open/not sealing. Smell the oil and see if it smells like gas. This is the easiest way to see if it's making oil. To fix it, get a new carb or injector. For oil in the spark plug holes, it is the valve cover gasket. Replace it. Do not tighten it to much, or it will leak just like the current gasket.
Aiyana Originally Answered: Several minor problems with my car involving engine oil. Please HELP?
I can't believe nobody mentioned the flashing oil light. The light will flash if you lose oil pressure, even momentarily. I think you're mis-reading the dipstick and running low on oil. Be sure to check the front and back of the dipstick. The lowest dry point is where the level is - not the highest wet spot on the dipstick. The oil in the dipstick tube has a tendency to rub off on the dipstick when inserting and removing it. For the oil leaking into spark plug holes, get a valve cover gasket that includes the new grommets and the spark plug tube seals. Like this one: http://www.checkerauto.com/ProductDetail...

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