OutdoorKing Repair Forum Forums Repairs and Maintenance Questions on Engines Questions on Other Engines Victa (chonda) V40 engine-something wrong

I sold this mower last month and it was returned yesterday. They said it was used twice and now won't start. There is excellent spark and the carburetor is new and has since been cleaned. If I hold my finger over the spark plug hole there seems to be very good compression and suction. I don't have a compression tester or leak down thingy. The PCV valve does not appear to be blocked as there is no sign of oil in the return pipe. I have primed it with fuel and on rare occasions it will try and start with backfiring and chugging but never full roar running. I think I will junk this engine as I feel there is something wrong inside, perhaps timing, but before I do I wonder if anyone had any ideas. I am thinking of pulling off the exhaust to see of it is blocked but that is just my clutching at straws I think.

Sparker, first thing I would try is a squirt of starter fluid in the air cleaner to see if it wakes it up and also check the valve clearances, Chondas are a bit notorious for this problem. Also is the choke fully closing

Hi NormK, Already did this. Valve clearances were fine. When I squirt some fuel into the spark plug hole or carby, as a rule-Nothing! but a couple of times there was some slow rev irregular chugging with backfires and then it stopped. That only happened about twice out of twenty times. Normally there's nothing.

Don't know anything about the V40 but have check the flywheel key for shearing?

I haven't checked that. There's no "lash" on your hand when you pull the starter cord. It's all smooth pulling so I haven't gone in that direction. I did end up taking the exhaust muffler off but no result there.

It seems to be a garden variety Chinese Honda OHV copy. I have seen a variation of it on one other in house department store brand, so I presume examples have found their way onto some el cheapo domestic grade mowers in the U.S.

Nice engine when it works, though can't handle the super tough stuff like a Victa two stroke thrives on.

Hi, I had a rockwell with a chonda do the same thing, ended up being a faulty HT lead (spark plug lead) earthing to the head area
Hope it helps

I might add, when checking spark all looked ok but when back on plug in situ, must have been close enough to earth out, would occasionally start but not rev at all

Hi Sparker, try a new plug, just cos it's firing at atmospheric pressure doesn't mean it's firing under compression. Your symptoms sound spark related, ive had a few like that and as rusty.ute said the HT lead can sometimes earth out.
Drain the fuel bowl and check for water.
Also worth looking at is the valve gear and valve clearances, 0.15mm intake, 0.20mm exhaust.

As Bigted said plugs do misfire under compression. As just repair a FS240 that only misfired under acceleration and smoothed out at full speed. Felt like I had a drive shaft or gearbox problem. Then I remember it had one little 10mm plugs that I have a lot failure with.

And as for feeling backlash in the recoil a sheared flywheel can allow the flywheel move on the crankshaft enough to cause to ignition to off enough as to not light up the fuel. This shearing is usually cause by impacts. It can shear and actually bind the flywheel in the new position; hence, no play. I had a few that were a bear to get off because of this.

Thanks for the suggestions. I tried a second plug and a different magneto but there was no change. I do remember this engine making very loud "staccato" noises that were normal but very loud. It's not worth spending any more time on. I'll change the engine out with an old Briggs and Stratton side valve. Good old standby's that don't cause me these mysterious troubles.

Guess what! The suggestion here was to check the flywheel key and as a last resort I took off the flywheel after checking the key and had a look at the PCV valve. What a mess - Firstly there were 2 valves on top of one another, there was no proper gasket just some silicon crxp that had not been applied correctly and a bolt hole in the cover looked like it had worn out on one side. What's more the gauze had been replaced with some other wire mesh stuff.
Unfortunately, I didn't have another cover and gasket so I had to do much the same and I used a washer to cover the gap in the bolt hole in the cover. I only used one PCV valve.
Put it back together gave it some fuel and it started with my drill first time! It still has that extra loud sound to it though. Could that be because of high crankcase pressure and bad PCV chest seal?