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Ideas on removing this nut my problem is there is no way to stop the thing from moving when I try to undo the nut

I made up a bar with 2 blots coming out of it that slipped in to the hols you see under the nut but all that done was bend the bolts not let me undo the large nut

Spread it with a chisel, heat, impact wrench, I have used them all with luck.

looking at blades i think its left hand thread

Nope. it is a Victa ( Mustang by the looks of the skirt on the baseplate ) and the thread is a standard RH one.
The trick is to use a rattle gun, they will fall off.
If you do not have access to one the move the piston to a little before TDC if it has a Power torque engine or BDC if it has a B &S , Honda or Tecumseh engine.
Stuff as much nylon rope down the plug hole as you can.
Then give the spannar on the nut a sharp smack with the biggest hammer you can find.
The logic is the rope prevents the piston from going up any further so the shock load is applied to the nut.
The 2 stroke engines complicate doing this because you dont want the rope goind down the transfer port.
You can buy a tool called a piston stop that does the same thing but make sure it is the plastic one not the steel one which can damage the piston.

The other alternative is to remove the muffler and stuff the rope through the exhaust port so it is totally inside the cylinder .
This has 2 problems
Some times the rope gets mashed so it is hard to get all of it out without removing the head.
Secondly it will usually dislodge hard carbon deposits around the exhaust port that will score the piston so you will not get the usual 30 to 50 years of service life from the engine.

what a spot yes its a victa what a spot from the bottem

i have had the head off already (will make a gasket) so stuffing with rope not a problem does it have to be nylon i do have string here but is there a danger for braking the head in doing this ?

its a 2 stroke you prob already know this and has no spark im hoping the u metal thing coil ? needs ajustmant as its to far away to produce the spark

Never seen a head break.
However it needs to be a hard sharp smack after you have cranked the piston around to compress the rope.
Beware of a slow twist say using a 2' bar as you can bend the crank and you need a $ 75 tool to undo the crank pin.
Personally I would be inclined to pop around to yout local garage and ask them to give it a wack with a rattle gun, a 10 second job.

As for the spark it will depend upon weather it is an early or late engine.
The early engines ( close fining on the barrel ) use a seperate coil and trigger ( little silver square under the carb, usually pop riveted on )
The latter engines have long & short fins widely spaced as the earlier engines over cooled in Australia so they must have been really cool in the UK.
The latter engine uses a combined trigger & coil which are now $ 185 wholesale as Briggs & Stratton is trying to get rid of all the old Power torques so they can sell more Chineese Briggs on a dish.
Before you test the spark, remove the cross wire from the switch so there is no accidental earthing of the spark.
You can fit the old system to new engines I do it on a daily basis.
If you are going to replace the nut then just use a nut splitter on it.
Do not hit it with a hammer & chisel as the shaft has a habit of bending.
If you can wind the nut on by hand tright up to the plate then it needs replacing.
They are a 10 year service replacement item.

I have used the rope method when I worked on 2 cycle snowmobiles engines to remove the clutch's. It worked good on them but the only thing is be careful you don't feed the rope into the intake or exhaust ports. I don't see what different the type of rope you use, but I used nylon because it just happen to be what I had at the time. If you do use the chisel method make sure you support crankshaft so you don't bend it.

bertsmobile1 said:

Nope. it is a Victa ( Mustang by the looks of the skirt on the baseplate ) and the thread is a standard RH one.
The trick is to use a rattle gun, they will fall off.
If you do not have access to one the move the piston to a little before TDC if it has a Power torque engine or BDC if it has a B &S , Honda or Tecumseh engine.
Stuff as much nylon rope down the plug hole as you can.
Then give the spannar on the nut a sharp smack with the biggest hammer you can find.
The logic is the rope prevents the piston from going up any further so the shock load is applied to the nut.
The 2 stroke engines complicate doing this because you dont want the rope goind down the transfer port.
You can buy a tool called a piston stop that does the same thing but make sure it is the plastic one not the steel one which can damage the piston.

The other alternative is to remove the muffler and stuff the rope through the exhaust port so it is totally inside the cylinder .
This has 2 problems
Some times the rope gets mashed so it is hard to get all of it out without removing the head.
Secondly it will usually dislodge hard carbon deposits around the exhaust port that will score the piston so you will not get the usual 30 to 50 years of service life from the engine.

Click to expand...

I was really sick yesterday. I should have not gotten on the forums.

Being in the USA where the government placed a fake safety ban on Victa so it could not sell into the "free market" you have most likely not seen many Victas
I OTOH live in the country where they were made and rebuild them as a side line to the small engine workshop so I see a substantially larger amount of them.
No need to feel embarrased.

Done it I had a air gun in my tools but thought the compreser was not man enught but I had changed the air gun I had and never tryed it and my new gun works ok but not for long but enught to undo the stubrn nut yea

Now for the next step trying to figure out how the coil and carb all work together

Here's a pic after it got it off looks like the gaps about right so need to cheak the wires any idea on this any info would be great worked a fair few 4 strokes but don't know what am doing on this as all seams to be run through the carb ???


Thanks in advance

OK lets take it from the top.
Why are you pulling the engine apart ?

What you have there is a Powertorque Mk I with an LM carburettor.
The coil is controlled by that small silver box with the brown wires at one end and the black wire at the other.
Usually the rivet holding it on becomes loose and can not maintain a good earth. So you get an intermittant ignition.
The on off is where the wires go into the carb

The rest here are general instructions.

To remove the switch set the throttle control fully open.
pull the black earth cut out wire out of the rubber boot If you spin the engine at this stage you should get a spark.
If the control module is loose slip apadle pop stick under the end with the brown wires to keep a good earth at the other end.
Now pull the boot and brown wire strait out together.
The boot and the rubber tip you should find on the end of the brown wire are service items and should be replaced every 10 years and your engine could be 40 years old.
There should be a serial number and year stamp in the block under the carb, The year may be full 4 digits or shortened 2 digit.
The boot goes over the wire before the tip is replaced or you bugger the boot.
When you turn the engine off a peg in the carb hits the rubber tip on the brown wire & pushes it foreward so it contacts the black wire and shorts out the coil.
The only thing that opens the connection again is the springyness of the rubber boot which degrades over time.

The entire carb is on a boynoet type fitting so you push it in against the spring washer, rotate it 1/4 turn & it will pull strait off.
The two PVC tubes should also be replaced.
The upper one in the photo is the govenor and it slips easily off the carb end.
To test the diaphragm, blow & suck through the tube you should hear & feel the diaphragm move in and out but it must be airtight, if you can blow or suck continously then the diaphragm needs replacing.
Under the carb the second tube goes to the decompressor which sits on a plastic damper in the carb, be careful pullin it off as the white damper tube is easily broken and is NOT REPLACEABLE so the carb body is then trash.
Same test here blow & suck to activate & deactivate the decompressor diaphragm and again only a small amount of puff, continious a flow then decompressor need repairing or replacing ( late ones are not servicable )

To remove the throttle cable, set it to the stop position, loosen the clamp on the snorkel tube and pull the tube back exposing the throttle cable.
If you are right handed hold the carb in your left hand with the throttle cable at the 3'0 clock position.
Grasp the throttle cable in your right hand then twist it to the right.
The ball will pop out of the cam and the the outer cable is pulled directly back towards yourself

Now wash the carb body thoroughly before attempting to remove the diaphragm cover.
If the engine was responding to load properly and it tested OK when you blew & sucked through the tube, then do not remove the cover as once opened the diaphragm will need to be replaced.
The diaphram cover and spring cap are removed together and will pop off by inserting a screwdriver in the join and twisting . You should see a few pry points.
When it does there is a long spring that will fly out
The retaining plate now exposed has a keyhole retainer remove it.
The diaphragm simply pulls off the barb on the end of the poppet valve, but it is a very tight fit as it has to be airtight for the diaphragm to work
There is a shorter spring under the diaphragm, then a lift guide ( spider ) , then the throttle cam & optional brass compensating shims ( up to 4 of them ) .
The valve comes out from the other side & is the only thing that goes in from that side.

The primer cap can be removed, the screw in the middle is the main jet.
The float and needle will generally fall off and the needle is tiny so do it over a bowl.
Generally there is nothing that needs servicing inside the float chamber they never ever give any problems unless the primer bulb need replacing.
Once removed the O ring on the primer plate will need to be replaced and when you replace the primer plate, push it in around the edge then tighten the main jet , just snug or you will break it or the plastic tube it goes into.
The most common reson for replacing an LM carb is a gorilla on the end of a screwdriver ripping out the main jet tube.

The manifold on the engine should also be removed ( 2 screws) it has 2 O rings on it and both should be replaced ( 10 year sevice items )

its alive

was playing with it untill 11.30 last night and got most of it together there was a brake in the spark plug cable joined that and there was a problem with the lever mech as when you pushed it to run it would not move the bit in the carb to so it was allways shorting out took it apart and oiled and moved the cable around to free it up put in a made up head gasket but did think i better not try and start it up that late at night (this was hard after working on it so late)

got up this morning added a few more bits sharpned the blade added it (can any one say what tork setting this should be set at)

took a fair few pulls but started and then would start first pull once had it going i think it could do with a full service kit but will leave that for some one else as the price of the kit will vasty bump the price of what i paid for the mower

can i say thanks for any one that commented and a quick shout to bertsmobile1 for the long but easy to follow guide must have take a while to post the last one

and answer to the tork setting would be great

its so satisfying after working on a mower for some time just to get that woho feeling after all the time spent its only a hobbie and dont make realy any money with playing with them but its a good time spent that makes a bit of beer money and more just for the feel good factor when it goes right and saves another mower from the scrap heap this feels better then most as its so unusual with luck i hope it will go to some that likes to collect them but who knows

ps when doing the work on mowers i dont take work from local repairs places in fact i say togo to a local one(that i use for parts) i will do if asked if its a family member or next doors but most of what i do is work on my own bought or scrap or tip mowers and think every one on the fourms some people like me but from reading soom posts there are some if not quite a few professionals on here giving there help for no more than a thanks so can i say a clap and thanks to all that give help for very little in return and in the hope i can do the same for someone else

Blades are torqued to 15ft lbs.

If you did not set the throttle to full when you reassembled the cut out switch then the end will get messed up and most likely will shortly fail
There is a small extension made to fit on the end or the spark plug lead which looks some what like one of the old screw in supressors.
And the nickel plated wood screw in the end of the plug cap is correct

Full 20 year service kit is
5 "O" rings, $ 6.00
3 lengths of PVC tube, $ 2.00
a govenor diaphragm , $ 8.00
A cut out boot $ 2.50
A cut out sleeve $ ,50
A fuel filter $ 7,00

Optional items are
Primer plate $ 15
Air filter $ 5
Decompressor $ 18
Plug cap $ 3.00
Spark plug $ 7.50
Muffler $ 45