OutdoorKing Repair Forum Forums Collectors Corner Rotary Victa Corsair scored cylinder

Thanks Mark. For the record I took the piston out and gently massaged the rings and now they move a lot more freely, cleaned what I could in the ring grooves. Re-assembled the whole thing and no cigar - did not want to start. If anything it feels as though there is less compression than when I started. Now I should say that the large o-ring underneath the starter mechanism is perished but I put it back in with a bit of grease, not sure how much this affects the compression. So it would appear that the rings are faulty but I've rung around and there is a mower shop that might have some in stock and is open.

I do have another engine for the powertorque series, very similar and from what I can see it has a cleaner cylinder bore but I couldn't get the crank pin off this one. A little more rusty than the Corsair but may have a go at swapping the engine over.

Thanks for letting us know what you did, there are alot of reasons for an engine not firing into life.
Some good reading on this site.
Try this thread:

https://www.outdoorking-forum.com.au/forum/ubbthreads.php?ubb=showflat&Number=31919&page=1

Just an update on where I'm at. I have changed the o-ring under the starter, the head gasket and tracked down some piston rings but they were taken out of another machine, the guy at the mower shop assured me that they'd be fine. So having done all this, the machine still does not fire up although the compression is very strong and noticeable.
What is troubling though is that when you pull on the starter, smoke appears, it appears to be coming from the decompressor area. Whipped off the muffler, can't see any piston damage but the smoke worries me, any ideas what's gone wrong?
Should add that I squirted a little petrol in the spark plug hole to see if it would start.

Hello tiger,
Seems like you have made some good progress.

The smoke seems to suggest it is trying to start.

I would see if it fires with a spark plug blocking the decompressor port.

If it fires, then you have a decompressor issue.

Also, if a 2 stroke is flooded with fuel, it wont start.
Remove the plug, clean it, pull the starter to drive excess fuel out, reassemble & try again.

G'day again Mark, you were right with the decompressor. Stuck an old spark plug in and it fired up. The decompressor is a sealed unit, I don't suppose they can be cleaned out/serviced can they? Changing the head gasket and o-ring underneath the starter all helped but no doubt changing the rings really did the job. Thank you again for your support.

With those decompressors, I clean around where the valve seats & put a small piece of wire through the tiny hole in the top where the hose connects.
Check the black plug on top, is it a tight fit & sealing.
Use a piece of hose to test that the valve closes with suction.
Then see if it works in an engine.
Yes, I dislike the fact that you cant strip and clean this type.
With the valve out, youll soon find out if you have a good starter rope.

Thanks Mark, gave it a clean with the decompressor and it seems to work better.
One thing though the fuel tank is a little loose under the cowling. It doesn't seem to affect performance but I like everything to be nice and tight but there are no screws/tabs/clips around that area. Are the fuel tanks suppose to be a little loose?

Yes the fuel tank just sits there, originally there was a big foam washer that went between the cowling and fuel tank around the fuel filler to hold it a litthe bit tighter but these days most of them have broken up and disappeared. I am unsure at present if the foam washer is available as a part.

Thanks Joe, I noticed that there are tabs on the fuel tank and I thought they would serve some purpose. Probably wouldn't be hard to fabricate some sort of foam washer, I just like everything to be nice and tight.