Evolution .46 help
 

recently put this engine back together after its been sitting for months, due to me cleaning it and not feeling like putting it back together. I'm having some problems now though with starting and running it. It is extremely hard to keep fuel in the line for one, and after i prime it enough so that it reaches the carb, the fuel creeps right back into the tank after a few seconds... therefore not letting the engine run for very long. Another thing is that when i do sometimes get it to run for a while but remove the glow driver, the engine dies instantly. I know that the driver is not the problem as i charge it regurally nor are the glow plugs as i tried 5 different new ones on it. I'm thinking not everything is sealed or maybe the carb has just gone bonkers and i might have to get a new one, but want to check if theres anything else i can do before that. Any suggestions??

Dave

RE: Evolution .46 help
 

I'm not an engine specialist but certainly sounds as though you did not get it put back together properly, like maybe the cylinder liner,or valves if a 4 stroke? You could help by stateing what engine it is, why do so many ask for help but neglect to give pertinate info?

RE: Evolution .46 help
 

Little things, like tank height, can make a big difference. How high is your fuel tank? If it is at the same level as the spraybar in your carb (the spraybar is where the fuel comes out to go into the engine), that shouldn't be a problem, assuming all else is nominal (as it should be).

How is the engine's compression? Is it the same, or close to the same, as it was before you disassembled the engine? It is important that the engine's sleeve (liner) be put back in the engine the same way that it came out. And it is equally important that the piston go in the same way it was when it came out. If not, you may have compression (seal) issues.

Did you know that the two-stroke glow engine has two important seal areas (not counting the close fit of the crankshaft to the crankcase)? The top of the piston forms the usual compression seal that most of us think about, but the piston skirt (lower portion of the piston) must also seal well in order to draw fuel from the fuel tank and then to pump the fuel/air mixture into the combustion chamber. If the engine is assembled incorrectly, or if there are leaking gaskets, you will not be able to pump fuel from the tank, or inject the fuel/air mixture into the combustion chamber properly.


Ed Cregger

RE: Evolution .46 help
 

First, put an OS A3 plug in that engine. If you have the counterweight on the prop shaft, remove it and promise to never put it back on there.<div>
</div><div>With the A3 plug, the engine will prime differently than before. Get a good prime and then try to crank it. </div><div>
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RE: Evolution .46 help
 

I know that i put everything back together as i have done it before at least twice with the same engine and it worked. The compressrion is about the same as before...maybe a tab bit lower.

Ed- how exactly do you check for a proper seal at the bottom of the piston?

blw- I'll make a note to get a few of those on my next trip to the lhs.

Tedmo - look at the thread title.... Evolution .46 help



thanks for the help so far

Dave

RE: Evolution .46 help
 

By seeing how well the engine can pull fuel. If it does that well, the rest falls into place.


Ed Cregger

RE: Evolution .46 help
 

What kind of plane is the engine in? Do you have it fixed yet?