OutdoorKing Repair Forum Forums Repairs and Maintenance Questions on Walk Behind Lawn Mower Frames Victa Lawn Mower Frames VICTA COMMANDO HELP!!!! WONT START

hi everyone,

i am 15 years old and recently got my hands on an old victa commando :), its my first mower and i want to get it going, i have rebuilt the carby, fixed the coil and replaced the spark plug but it wont start at all! can anyone suggest the best way to solve my problem

thanks

I would assume its a power torque engine??


Got good compression??
Got spark???
Got fuel??
Fixing it is a process of elimination.
This is generally how i do it.


Got good compression??
Hows it feel when you sping the blade plate by hand (plug lead off)
Pull the starter off and grab a torch and look up the bore.
Should be very few scratches etc.
If its not looking the best, Pull the muffler off and look at the piston. hows it look?? All scratched and horrid and its no good. If its a bit so so,
Pull the inlet off and look at the piston on that side.

Then theres crankcase compression.
Spinning the motor, are the bearings grumbly? Sloppy?? Bottom seal OK, is the top of the flywheel wet or oily?
The starter seal o-ring, is it OK?
Is the decompressor OK? It can be replaced with an old spark plug for testing.

Got spark???
Test with the plug out resting against the motor.
Test with plug out and throttle in the off and start and flat out positions. (always do this after removing/fitting a carb)
Test without the plug. Watch not to zap yourself.

Does the ignition module have a good earth??
Is the plug a known good plug?? Just because its new does not mean its good. Not common but not impossible.



Got fuel??
Spark plug wet?
When the starter was off was it wet in the crankcase.

You rebuilt the carb, if its dry,
Is the fuel tap blocked, do you get a good flow out the fuel line?
Is the jet blocked?
Needle and float need to be matched so they work in that 'primer face'. Sometimes with a short needle the float will stop moving (hit internally) before the needle seals up. And the opposite where the needle takes up before the float has moved up enough.
Fuel height in the carb is directly related to mixture.

thanks i will check all those things today, something i forgot to mention was that the spark plug is dry all the time. does that mean there is no fuel getting into the engine?

UPDATE: i found that the decompressor is stuffed so i replaced it with a spark plug for now. i have found that the intake is sucking and blowing :S, i have no idea what this means everything else seems ok, it has a really good spark and the comp feels ok, i have also noticed that the piston is quite scratched on both sides. this thing just wont start

thanks

Does it have spark, pull the plug out, reconnect it to the wire and rest it on the head of the engine. Put the throttle in the run position and crank it over while looking at the plug.

If you have spark try putting a teaspoon of fuel down the plughole, refit the plug and try firing it again.

The intake will suck and blow as its a piston port motor.



Does fuel run freely out the fuel line??
Is the main jet blocked? Is the main jet passage into the carb blocked??
Needle and float in the carb OK and matched?? Fuel height in the chamber is important.
If the crankcases are dry i usually dribble a bit of 2 stroke oil in there.

You could try a teaspoon of fuel in the plug hole, if it wants to go then you know that you have an issue with fuel supply.


If it has bad compression and bad crank seals it might not want to run.


Good spark outside the motor does not mean good spark in the cylinder at about 7 times atmospheric pressure.

tried that and still nothing

how many crank seals are there? there is a big one in the top.

it has to be that because ive tried absolutely everything and still nothng

If you put a spoonful of fuel into the cylinder and it wouldn't fire, the problem is not intake sealing or carburetor. The first problem to consider is whether the spark plug is fouled. You said it has spark - did you check this with the actual spark plug you intend to use? Was the spark blue and strong, or red and weak?

If you are sure it has good spark, it sounds as if the compression may not be as good as you think. You could try removing the decompressor from the cylinder head and temporarily screwing in a second spark plug there to plug the hole you took the decompressor out from. Put a screw into the air hose that goes to the decompressor, to plug it. Then try the compression again. It should be extremely strong, so it is quite difficult to pull the starter cord. If it isn't all that strong, there is one further test to confirm the problem: leave the plug that replaced the decompressor in place, take out the original spark plug, put one spoonful of clean oil (engine oil or 2 stroke oil, it makes no difference) in through the spark plug hole, then put the spark plug back in but do not connect the wire to it. Pull the starter again, and see if it has become harder to pull. If it has, you have a compression problem.

how strong should the spark be?

and would a 50 to 1 fuel mix be part of the problem?

When you pull the starter cord while looking at the gap between the spark plug electrodes, you should see an even string of blue sparks, and the sparks should not be thin and spindly.

You said you have scoring of the sides of the piston, when you look at it through the ports. That will be due to lubrication failure at some time in the mower's life. One way this can happen is due to blow-by (gas leakage past the piston rings from the combustion chamber) blasting the oil film off the cylinder walls, which normally means the piston rings are worn out and the engine has lost compression. It could also have been that someone ran the engine on straight petrol at some time, or it may have happened more slowly due to low quality oil, or insufficient oil, in the fuel. Victa specifies 25:1 petrol to oil. It is a good idea to do as they say unless you are sure you know more than they do. Note: Victa did get into a promotional deal with Valvoline in which they said they approved of 50:1 as long as you bought the oil from them with a Victa brand on the oil bottle. We don't know whether their engineering department signed off on that, or it was just the work of some genius in marketing.

That mower needs a 25:1, as you already have soring, I would suggest not trying a 50:1 mix, however, the 50:1 mix will not stop it starting it will just damage it once it does.

I would suggest a full compression test, as you have already popped a spark plug in the decompression socket, now would be a good time.

Disconnect the spark plug lead, and flip the mower onto it's side, then turn the blade disk by hand, anti-clockwise.

You should feel 2 points of resistance (compression points) per revolution, one should be distinctly stronger than the other.

Now, flip the mower back up, and pull the cord, not to hard, just pull it out at bout 1/2 the speed you normally would, it should get very hard to pull at some point.

Let us know how hard it got to pull the cord, and how strong the 2 resistance points felt when it was on it's side, also, how great was the difference between them.

Also, is it a possibility you could take a clear photo of the scratches on the piston, when seen from the exhaust port.

there was a difference between the resistance, when the mower was flipped on its side, one point had double resistance when compared to the other.

when the cord was pulled at 1/2 speed the resistance was good, it wasn't impossible to keep pulling but it has a reasonable amount of resistance

i will upload some photos now

To me, that sounds like the compression is at least reasonable.

At least reasonable enough that it would at worse run rough, as opposed to not running, the pictures should help though.

Lets give the spark a full test (using the above mentioned methods) now theres 2 ways i tend to do this, you can choose either at this point.

1)Remove the rubber boot from the end of the spark plug lead (should be fairly easy on your mower) but leave the contact screw in, then, using a clamp, or vice-grips (locking Pliers) secure the lead so that the screw is 3mm from a clean, unpainted metal part of the mower (make sure the screw is not making contact with the mower, or the pliers/clamp)

or

2)Get a spark plug that you know for sure works, and using wire cutters, or a handheld rotary tool, remove the bent piece of metal that the spar travels to, crating a 3mm or so gap between the centre rod, and the outer rim, then clamp this plug to the mower, making sure the centre rod is not contacting the mower, but the outer metal casing IS, and connect the lead.

Take the mower to somewhere with low ambient light (inside a closed or semi closed shed is good, but any were dull will do) and give the cord a few strong, fast pulls, with the throttle set at run (make sure the fuel is off, and there is no spark plug in the spark plug hole, also, it is best to make sure the test spark will be away from the spark plug hole, to avoid lighting any expelled fuel)

What is the spark like? (colour? [could be yellow, or more a blue/white] strength [wispy and thin, or strong and fat] and any accompanying noises)

That does not look too good to me, however, seeing as you are confident in the compression, lets see what we can work out.

It is possible this engine will either need more serious work, or perhaps it would be an idea to grab a new one, as to be honest, even if we get it going, I'm not sure it will run all that well.

However, lets see what we can do for now, we may at least get it running for you, which will give a better indicator of how bad it actually is.

That piston is no good at all, if I had one like that the whole block would be in the scrap bin, you may get away with a new piston and a hone but if it came to boring it out you could get a second hand engine for cheap or free.

To be honest with you mate, Joe's right, I mean you could give it a go, and see what happens, but if you so manage to get it to actually start, I'd put my money on 'Rough as guts'.

Are you in NSW or ACT, I might be able to point you in the direction of a good place to grab a cheap engine for it ($10-$20) or if your close enough, I should be able to dig one up you can have.

Whats the inlet side look like???
The shot of the top of the piston would have been better if the piston was at the bottom of the bore so we could see what the bore is like.

That would go in my work it out later pile, i couldnt sell a mower that looked like that inside even if it did run.
Having said that, there is a good possibilty that it would still run. (depends how bad the inlet side is. Looks like the exhaust side is well and truely stuck in the piston)
So its probably worth testing further even if its just to work out the value of some of the other parts.
Spark is ok, the coil is good.
Fuel delivery, check out the carb and if its good to reuse.
Working starter.
Head thats not warped. (this combined with the piston like that will stop it running for sure)


You would probably find that if you remove the piston and the rings were not too difficult to get out, the piston could be cleaned up with some sand paper, wet rubbed with WD40, clean the ring grooves out and fit new rings hone the bore and it will work fine for many more years to come.
Or fit new piston and rings.

Before i get bagged out for being rough. For a mower for myself i would do and have done in the past. Its just a mower, its not a light plane engine, or a motorbike. If it does let you down thats the perfect excuse to kick it and go inside and grab a beer or 10 come back out and sit in a chair and try and talk to it about its problems. Sorry not an option for you at 15.
Its a basic engine design, to work right it needs to be spot on, to just work, its basicness is in your favour and theres lots of forgivness in the design.




Test the spark as mentioned above and try some 2 stroke fuel in the plug hole, see if it will at least give a cough.
Probably little point now seeing as you have the head off.


The crank seals. The top is the o-ring under the starter. In the bottom its part of the bearings. Its a special bearing made for Victa Power torques, it is open one side and has a heavy duty seal built in on the other side.


To go any further with that motor you will need to obtain or make a special tool to undo the conrod bolt.