OutdoorKing Repair Forum Forums Repairs and Maintenance Questions on Engines Questions On Victa Two Stroke Engines Victa FUll Crank Rebuild

Hi I am new to this forum. Recently i have rebuilt a power torque victa (half crank). I have now got hold of a clapped out full crank victa 2 stroke. I plan on stripping it down and cleaning it up and get it going again for something to do. I've stripped most of it down but i have a number of questions:

How do you remove the fly wheel on the top of the engine?
Does any one have an exploded view of the engine?
Are the crank case seals the same as the more modern half crank seals?
And also, are the parts for half crank engines interchangeable with these older engines?
Is there any instruction on fixing the pull start?


I have pictures which I will load up when I work out how. It has the G4 carby which I understand pretty well now. It's missing the end cap on the throttle so I can't give you a model number unfortunately.

picture

this the only pic I have of it before I took to it with the ratchet.

G'day nolan1986, and welcome to the ODK forums.

There's a how-to on uploading pics HERE

Your machine is a late model full crank 160cc, with side-mounted gear starter.

There are some free downloads of repair manual excerpts HERE; in the upper numbered sections. The rest require a paid subscription, but all you need is in the free section.

The 'Victa Gear Starter' and 'Victa Early Model 125cc & 160cc Spec\'s' docos should get you started. There are exploded diagrams in those.

Once the nut is undone, the flywheel should just slide off. If necessary, a little gentle persuasion, with two screwdrivers under opposite sides, can be used.

The seals and gaskets are different to the PowerTorque half crank engine, but the Powertorque piston fits the 160cc full crank engine. The seals/gaskets are quite cheap; see HERE for gaskets; HERE for seals.

Thanks Gadge.
What about removing the fly wheel?? I don't have any victa special tools.

Nolan
to remove flywheelyou don't need special tool
just use two of biggerst flat screwdrivers you have can find
maybe too people make more easy
one person to wedge screwdrivers under flywheel one screwdriver either side flywheel and using both screw drivers applied preasure to push flywheel up
at same time other person to give crank sharp blow with hammer, best maybe use brass drift of copper hammer to hit crank shaft, steel hammer damage crank threadsmake more plobem
for first time remove flywheel find help two person make easy preasure with screwdrivers pushing up hit end crank bang flywheel pop off very easy maybe some time need few good whcks

Thanks freebird. I was just having trouble with the nut. Thought there may have been a special way. In the end got my impact wrench onto. Was just jammed up with crap but came off easy after that.

when replacing piston, do you need to use expansion ring??

The new piston doesn't come with one?? Why is this? Does this ,make a difference?

if he set didnt come with that ring then dont use it or the old one !!! some do have but now most dont soo , if its there use it , if not dont stress

+1 to vccomm here. It's due to a change of ring design. The late PowerTorque bottom ring doesn't use an expander; not sure when this came in though.

BTW, did you check the bore size? 2.420"/61.47mm is standard bore.

It was more common to rebore the full crank barrels back in the day, than it is now; oversizes go up in .020"/0.50mm increments.

Ok so I need some help. I've cleaned and rebuilt the engine. Mounted it. I replaced the points with a brand new ignition module.
I managed to get the mower started and it ran. Thought I'd done a good job. Let it run for a bit then stopped it. Tried starting it again and it wouldn't go.

Same for the past couple of days. Sometimes can't get it started, then it starts. I stop it, sometimes it's one pull start when it's warm others it won't go at all.

I've checked for spark, which I have. Checked the carb and it's getting fuel. Thought the throttle cable might have been playing up, but not the case. Has compression. I took the engine off and tightened up the crank case nuts more because I was getting a little bit of oil aroufnt the crank case seam.

Does anyone have any other suggestions?? I was hoping to get it to be a one pull start.

Air leak on the carb, try a quick squirt of starter spray in the carb and if it starts you know it is a carby problem

Do you mean spray the starter spray in the spark plug hole?? Or take the carry cap off and spray in there?

Also, an air leak. Like the carry body has a fracture? Or the on the spigot that is screwed to the engine is worn?

And what is the air leak doing? Causing the engine to flood?

For me I not only want to fix the problem I'd like to understand what the root cause is as well so any more detailed advice would be great help.

Hi Nolan, take the air cleaner off and spray in through the carby, not a lot, just a whif and see if it starts straight up. Carby air leak maybe around where the carb connects to the barrel, probably unlikely but is possible. This won't cause the carb to flood but it reduces the suction through the carb on start up. Then there could also be some issue with the carb internally, not sure what the situation is there.

Ok norm. So take the air filter cap off and squirt some in there.

Are you saying I might have an air leak in the air hose?

G'day folks,
It's easier to remove the air filter on these, than it is to pull the snorkel off the carby. Then just a small shot of Aerostart or similar down the tube, and pull it over immediately.

Nope, the likely spots for intake air leaks on these are, between the carby and the intake spigot, or between the spigot and the intake port on the barrel.

These are both o-ring seals, and the o-rings get hard with age and heat. Then they don't seal very well.

And the air leaks in these positions is what could be causing the engine to flood??

I haven't had a chance to get another look at it since the weekend.

When I was pulling it over I checked the spark plug and it was wet with petrol and could see petrol in the cylinder then when I replaced the plug that would be when it would go then. So I suspect flooding is the issue. Especially having read some of the other threads on here.

So sorry if I'm being annoying. You blokes obviously have your head around it better than me.

Gadge you are talking about the o ring that goes on the outside of the spigot on the engine block and also the o ring on the spigot that is screwed to the engine block. And what you are saying is air leaks in these spots causing the engine to flood??

Hi Nolan, the possible air leaks won't cause it to flood, as Gadge said give it a squirt down the hose with starter fluid and see if it fires up, I would be guessing but once it gets running the flooding won't be an issue

Thought I would add a few comments to assist.

You mentioned earlier you replaced the points. From your photo I am pretty sure you mean the electronic ignition module. To date I have not found a failed full crank magneto fail, only the modules fail. Most of the time they can be re-riveted to the engine block and that fixes the spark issue. Please correct me if I am wrong.

A couple of items to check:

1) Try replacing the primer cap with a genuine Victa Primer Cap. Don�t waste your time with the aftermarket copies as most a rubbish. This is one of the only parts I use genuine because of the problems associated with many copy brands.
2) Check the primer cap needle and make sure the point that seals into the cap has not been damaged/ rounded in any way as this will cause flooding.
3) Replace the decompressor with a spark plug. I have had a few decompressors that gave the symptoms you indicated and simply replacing the units gave a one pull start. A properly tuned full crank engine should start first pull just about all the time. You can try the air test on the decompressor which is detailed within other threads. When I suspect they are faulty I�ll always find a second hand spare one to be sure.

Keep working your way through the diagnostic process and you will work the kinks. These are great first time engines to start learning on.

Thanks for the feedback norm and Jaffa. I'm still unsure of why norm means though.

Sorry should've explained. I ended up with two mowers from hard rubbish. The pics I took was the dirty of the two. The other mower, which I didn't take pics of, had a nice clean crank case and a plastic lid under the fly wheel where the points were stored. I threw those out and mounted a new ignotion module in there on one of the screw posts for the points. And I used that coii as it has the spade connection already and didn't require anymore mucking around.

The Prima cap is original. So I guess it's authentic Victa?? It didn't seem like anything wrong with it after a clean. So just replaced o ring on that. Yes, the needle is in with the pointy end down (or up). So the rounded end connects with the float. I checked this against other threads here and the service manual. However I did not replace o rings on carby spigot. Which I will do on the weekend.

Decompressor was stripped cleaned and rebuilt with kit. It operates as described on the forum here. When you suck on the nozzle the decompressor valve contracts and when blow into nozzle no air escapes.

so the engine. I stand there and pull and it does nothing. I leave it. Take spark plug out. Re assure myself I have spark. Pull the engine over a few times and the replace spark plug. Try and start again after three goes it turns over. I let it run for 10 mins. Stop it and then try warm starting it. It doesn't go. More mucking around then get it going again. Then try stop and warm start and it goes first pull. Let it cool. Try again and nothing.

So back to norms point, an air leak at the connection of the carby to the barrel reduces the suction and that could be the problem?? Is that how I understand it?

Also, the carby has been rebuilt as per instructions on the forum and Gregory's service manual. The carby is a LM carby. And no, I did not replace the black valve with a white valve that has lettering. The back of the carby though has that white adjusting screw which you can adjust the idle speed with.