I have a Victa Corvette Series 400 that I've had for 9 years never missed a beat, lent to the neighbour and now the it doesn't work anymore. Mower used to start within 2 pulls and with minimal effort, but for the life of me can't get it going again. I bought a carby rebuild kit and changed primer cap, seal, needle, diaphragm, cleaned the jet replaced ignition boot and plug but still no go. I have confirmed spark and can get motor to start if I fill the spark plug with petrol but that's it.
Just a thought, perhaps your decompressor has failed, if you remove it and suck on the valve it should stay shut. The only other thing I would suggest is to replace all the o rings, they are cheap and easy to do.
Also check under the mower to see if something like wire has wrapped around the output shaft and buggered the seal.
Just a thought, perhaps your decompressor has failed, if you remove it and suck on the valve it should stay shut. The only other thing I would suggest is to replace all the o rings, they are cheap and easy to do.
Also check under the mower to see if something like wire has wrapped around the output shaft and buggered the seal.
I haven't tested the decompressor but had a few lying around and tried them with no luck too. The only seal I haven't changed is the starter one.
Pull the starter out and put a wipe of silicone on the "O" ring that will seal that up. Get yourself a viton tipped float needle the plastic ones are too light and get suck up in the seat and don't let fuel flow.
Pull the starter out and put a wipe of silicone on the "O" ring that will seal that up. Get yourself a viton tipped float needle the plastic ones are too light and get suck up in the seat and don't let fuel flow.
Do you know if the neighbour had to refill the petrol tank at any stage? If so do you know what fuel? Also, is the fuel cap venting properly?
Cheers,
John
Neighbour used the whole fuel tank of what I had previously, they returned it dry. I got some new 91 ron petrol and used a new oil which I havenβt used before called ethanol shield semi synthetic that has premixed fuel stabiliser it says 50:1 but I mixed 25:1.
I used this oil in my whipper snipper at 50:1 with no dramas. So not sure if this oil is the culprit.
Can't find the needles on ebay at the moment the carbymaster usually has them listed and he is often on here. Only one I can find is this one but it has the primer cap, I would email him and see if he will send you one. .ebay.com.au/itm/VICTA-2-STROKE-CARBY-FUEL-PRIMER-BULB-CAP-KIT-FOR-PLASTIC-CARBURETORS/123864145772?
Can't find the needles on ebay at the moment the carbymaster usually has them listed and he is often on here. Only one I can find is this one but it has the primer cap, I would email him and see if he will send you one. .ebay.com.au/itm/VICTA-2-STROKE-CARBY-FUEL-PRIMER-BULB-CAP-KIT-FOR-PLASTIC-CARBURETORS/123864145772?
1. Remove the fuel hose from the carburettor and turn the tap on: a. If no fuel comes out, you either have no fuel, the fuel filter is blocked, the tap is damaged, or the hose is blocked. b. If fuel does come out, proceed to step 2.
2. If fuel leaks from: a. The float chamber, inspect to determine if the cause is a crack in the carburettor body, a crack in the float chamber cap, or, just the float chamber cap o ring. Replace the applicable component. b. The hole in the primer bulb, inspect to determine if the cut-off-needle is getting stuck, the float is leaking, or the needle/float have worn and when the float lifts, fuel is not being cut-off by the needle. If the float needle is getting stuck in the float chamber cap, clean the needle hole, seat, and needle, with carburettor cleaner. If the issue remains and for all other components, replace the applicable component.
3. If fuel leaks from underneath the carburettor or is found where the carburettor connects to the engine block: a. Check for cracks in the carburettor. b. Check for cracks in the inlet manifold. c. If no leaks are found, replace the carburettor to manifold and manifold to block o rings.
4. If no fuel is leaking from these points, check (In no particular order): a. The decompressor valve. b. Head gasket. c. Starter o ring. d. (With the spark plug removed) Around the crankshaft where it comes out of the engine. e. The exhaust port
If you are not seeing any fuel leaks and you have filled the mower with fuel, to test to see if it's making it to the spark plug you can check to see if the plug is wet, and you can also try removing the plug and pulling the starter. If fuel comes out of the spark plug hole then you know fuel is getting to it.
If you want to confirm if you have compression or not, with the spark plug disconnected but still installed, rotate the blade disc. You should find that approximately twice per full rotation of the disc there is at least a small amount of resistance. This is the piston compressing on the head side, and then the chamber compressing on the starter side. You can use this to determine at a basic level if one side or the other may not have compression.
If your neighbour returned the mower to you with the fuel tank entirely empty, it sounds like they ran it dry (Which isn't great for them but they should survive), or they left the fuel filler cap off and it evaporated (You should find oil remnants in the tank). It's also possible they straight fueled the mower when they ran out of your fuel, which could have done damage. Remove the exhaust port and inspect the side of the piston for scoring.
Ensure the engine is balanced correctly. The disc and blades should all be mounted securely. If a blade is missing the balance of the mower can be thrown off and the engine won't run.
Check the throttle position. The throttle may be positioned incorrectly, or you may need to move it to a different position for the mower to start and run correctly.
Ensure that you have the vacuum hoses connected correctly. The decompressor should connect to the carburettor body just next to where the carburettor connects to the manifold. The vacuum hose should connect from the carburettor cap to the engine body.
Ensure you're using the right springs inside the carburettor, and if required, try adding 1-2 brass spacer washers to the carburettor, under the cam assembly. Over time these components can wear, and as little as a third of 1mm can throw things off. While you're checking this, give the carburettor a full and thorough clean.
Check the cut-off wires. Remember, for PT's with the LM carburettor, you're supposed to use the short-type cut-out plug and the wire going into the carburettor which is lifted by the cam should not be covered with rubber. If it is, you're most likely using the long cut-out plug, which you should not be using.
I hope something above helps and I really hope your neighbour hasn't straight fueled the mower.
My belief is that if it fires with fuel down the plug hole the motor has not been straight fueled. The way to test the decomp valve is to take it out, put a piece of tube on it and suck on it, if the valve shuts it is fine. The other thing with a mower returned with an empty tank is often caused by the float needle not shutting and the fuel ending up in the crank. This is not the case with this one as it fires with fuel in the plug hole, if the sump is full, it will not fire. You can check the compression by removing the decomp valve and put a spark plug in the hole and see what it is like to pull over. These motors will run with quite low compression.
So I had some free time today and decided to try new new viton tip float needle I bought from ebay with no luck. I tried some different carby bodies, cams and poppet valves because when pushing on the diagraphm the poppet valve was barely opening on the other side but still no start. Tested the compressor and confirmed that good too. For some reason fuel isn't getting past the carby, the fuel just sits in the float chamber.
No chance of it running with the bore scored like that, hone may clean it up and a new set of rings or just pick up another mower for $20 is cheaper that way. Some you win on some you don't . I often pick up 5 for $50/60 and usually get 4 runners out of that
