OutdoorKing Repair Forum Forums Repairs and Maintenance Questions on Engines Questions On Victa Two Stroke Engines Victa V50 125cc/160cc (unsure) Reving hard.

I've gotta say, that knowing how it works makes everything simpler.
Have not had time to get onto the mower tonight, i had to help my parent out moving some stuff around.

Very much appreciated Blum, I'll have a read through all that as I'd really like to have a better understanding of how the carby functions!

Sure anytime I can help I will. Yes it good to know how it works and goes together. Gives one a better understanding in diagnosing and fixing. Glad I could help.

I've taken off the starter housing, as instructed by BigTed. WOW..... I never would have thought an O-Ring could stretch THAT much.... if I were to turn the housing upside down, the o-ring would simply fall off.

Hoping this is the culprit for the air leak. Will update tomorrow after I attempt to track down a ring from work/mower shop.

Ok, so make sure you replace the starter oring with a genuine one, we've all tried other ones , but they're either too big, or too small or too fat, or too skinny and just don't seem to work right bringing you back to square one quickly.
The loose carby on the manifold is a concern and suggest to me that the oring is either not there, or squashed and flat(and probably hard) and therefore not doing it's job, so the engine sucks air, runs lean and over revs. I've taken a pic of the manifold you have and it shows where the oring should sit. Once you replace it with a nice new soft fresh one the carby should sit tight and not turn upward like it is in your photo. This would also be a good opportunity to make sure that the 2 phillips screws that hold the manifold to the block are tight(one on top and one on bottom), but dont rush out to remove it and replace the small oring between the block and manifold as this rarely gets damaged unless it is disturbed.

If the carb still does not sit right after replacing the oring and wavy washer then we'll have to look at whether the 2 tangs on the manifold that hold the carb in place are intact or whether the carb itself is worn or damaged.

Awesome, I'll pick up the two o-rings tomorrow (unless the shop shuts 2 hours early again).

the manifold nodes were worn, so i purchased a new carby manifold and it now sits on there really well, new o-rings for both sides of the manifold and a new ring under the starter housing.

STILL getting over-rev issues

Going to try a trick i saw on this forum while searching around, two washers inside the carby to lessen the throttle.

Otherwise, i might introduce the old carby to a sledgehammer and order a new one ^_^

If all the seals are done, vacuum hoses connected and carby diaphragm in place and it's still overrevving then theres only one more thing it could be...... the bottom crank seal is shot. That would require removing the piston/conrod assembly and the crank and bearings. But before we go to that extreme there is a basic check you can do. Look at the underside of the mower around the crank and see if it's wet and oily, or just sweaty. Sweaty is ok, wet and oily is not a good sign. A photo for the rest of us is a good aide and removal of the blade disk will help coz being a utility it will be hard to see, otherwise try getting some light through the side chute.

ohh, yeah, try the washers first, if that fixes it then the crank seal should be ok.

Have you made sure the vacuum port at the engine end is free and clear?

Anyone know what size the washers are for the throttle fix?

https://www.outdoorking-forum.com.au/index.p...mp;cPath=193_514_225&products_id=591

Any and all dimensions if possible ^_^

I'm not up for waiting another week to try the fix =/

If you mean where the intake for the diaphragm is, then yes. i can blow/suck into the tube and it gives a little either way.

I've replaced the large metal plate behind the diaphragm with a smaller plate.

Visited a mower specialist to track down some brass washers and he advised that it was a common fix.

NOW my over-revving is sort of fixed, it's now searching through the rev range to find an idle, going from normal to over-revving to choking out.

Full throttle causing choking out and leaving the throttle on the starter speed is causing a "search" (up and down through rev range)

You guys really help, the carb info will be invaluable for my posting (I hope) I can start the engine but cannot make it run

Good stuff

Thanks Dennis