OutdoorKing Repair Forum Forums Repairs and Maintenance Questions on Engines Questions On Victa Two Stroke Engines vsx 160 over revving under load.

Hi guys, I have a vsx 160 the newer type with the straight inlet and bigger air hose.
The problem I am having is when ploughing through long grass the revs increase
like they should except it seems to pull too many revs. It returns back to normal
fairly quickly once you get back to shorter grass. Also on initial start up when on full
throttle it seems to over rev briefly and then return to normal. Any clues on how to
fix would be appreciated.

Merry Christmas to all.

Hi Joe and welcome to the forum,
Those symptoms are fairly common with the VSX160's as they tend to rev fairly low at full throttle with no load. I've personally not tried to rectify any of these but at a guess a new diaphragm may help and try playing around with different diaphragm springs as they do have different tensions depending on the color.

Hi bigted, thanks for your reply.
Thanks for your suggestions. I will try a new diaphragm and see if it improves.
The carby has the purple springs at the moment. Which springs would you recommend
to try? I'm not up to speed regards colour vs tension.

Regards, Joe.

Joe, i'm not sure which color relates to what load the spring carries either. A victa gold dealer may be able to help you out there.
I suppose a heavier spring will give you a higher no load RPM that should hopefully not cause it to increase rpm so suddenly through the long grass. A lighter spring spring i'm guessing would have the opposite effect, like i said, i've never tinkered with one to give you an exact answer.
So, i suppose trial and error in this case may be you're only friend.
Keep us informed on how it works out for you.
Cheers, Ted

Hi guys, just a quick update on this problem. I have swapped the diaphram with a new
one, without much difference. I thought it may have an air leak so replaced both manifold
and starter o rings without much difference. I then tried a new o ring on the starter shaft
which cured the over revving on start up however it still over revs in long grass. The only thing left to do is new carby springs which I will try next. I'll report back if successful.

Hi guys, I have finally solved this issue by shortening the top spring by two coils.
It now runs nice and quiet at full throttle and the revs increase as they should when
ploughing through the thick stuff but nowhere near the overreving issue it had before.
I don't know if shortening the spring makes it lighter or heavier in tension but the red
one I have is the lightest according to Victa.

I'm glad it worked out for you Joe, Well done.