During the last couple of weeks I’ve been having a major struggle with my Losi 8ight buggy. Keeping it running for more then five minutes with out the engine cutting out was almost not heard of. This is especially maddening because I’ve got a fairly new engine in it that has massive power.
First I tried setting everything back to factory settings to make sure there was enough gas flowing threw the engine. This setting it ran really rich, but also cutout after a few minutes. So I decided to take the whole engine apart to see if there was something wrong inside.
Again, nothing. No crazy abrasions on the piston or sleeve and the bearings looked great. So I sealed it all up and removed that from the equation.
I moved onto the fuel lines.. They appeared good. Lastly the gas tank.
I removed it and inspected it and did not see an issue. However I decided to pressure test it, buy filling the sink full of water and submerging it. Again everything was fine. Then I decided to blow into the tank to see if it could handle the added pressure.. Ta Da.. A little tiny air leak.
After hours of frustration I replaced the tank and now the buggy runs like a dream. Funny how such a little hole can cause a major issue.
Next time I’m starting at the tank and working to the engine for debugging the issue!
On a side note, the engine I’m running is the Go Tech 3 port Sport (standard plug) engine, with a 7.5mm carb restrictor. With my current tune I’m getting just over 10 minutes of runtime per tank! Once I really get this thing broken in I’m sure I’ll be getting more time since it’s still running rich. This engine is by far one of the best ones I’ve ran and would recommend it to anyone.
The only thing that I might do to the engine is change the cooling head to an after-market one. Since it seems a little flimsy and an after-market one would lower the engine temp by 30 – 40 degrees.