OutdoorKing Repair Forum Forums Repairs and Maintenance Questions on Engines Questions On Victa Two Stroke Engines no cutting power

Ive got a rebuilt power torque on a side throw that virtually dies in thicker grass. its a victa 550sp and previously would go through anything - any suggestions? I've got a victa o-ring set for it, not sure where they all go. Is it likely to be the (non original) carby, air leak somewhere....please help

Lean mixture does tend to cause 2-strokes to lose power without running roughly, but usually you would notice that it revs higher if the mixture is lean.

If you suspect that it does tend to rev higher as well as lacking power, the three O rings are a possible (and fairly likely) cause. One O ring goes at the carburetor end of the intake pipe, one at the cylinder end of the intake pipe, and the big one goes under the starter and seals the side of the crankcase. Any one of them could cause lean mixture (and all three of them often do so). However the fuel tank, fuel line and carburetor are also likely causes of lean mixture.

One important question is, what did you change between when it worked properly, and now?

Hi Grumpy
sounds like its running lean, does rev high without load. Will install the o rings (when
time permits) & see what happens, thanks for replying

Thanks for clarifying that Redeye. It seems like you can focus on lean mixture. If it happened suddenly without you having done anything to the carburetor, the O rings seem like the most likely problem. Someone posted the other day that if you smear a little engine oil on them when you are installing them - especially the one that seals the side of the crankcase, under the starter - you have a better chance of them staying in place rather than popping out of position. I used to do that routinely with O rings anyway for almost all applications, for various reasons, though for stationary O ring seals I usually used light grease because it's stickier.

Please tell us what happens. If you still have the problem after replacing the O rings carefully, we can go through the fuel tank/fuel line and carburetor processes. (Have to get a plastic Victa carburetor guy for the last stage of that, of course.)