spudulike

The 660 coil and flywheel are pretty robust and rarely go wrong. The flywheel has a steel taper and it is rock solid and can take a lot of torque on the location nut. Backfiring is a sign that the ignition timing has shifted which is strange. Best to pull off the flywheel, check the key and then reset the flywheel again and tighten - not sure how you locked the crank in place to do this but you should use the Stihl double ended plastic stop for this IMO. Not sure how the original flywheel "spun off"????? They usually need a damn good whack once the puller is fitted, to get them off! Are you in the repair game?? If the key is OK - I suspect it has sheared again as I don't reckon you are tightening it enough and am guessing you had removed it before......it is possible the flywheel coming loose has hit the coil and either damaged the internals or the flywheel impact has damaged the magnetism in the flywheel. I have seen this before - the magnetism loss in a MS461 so very much like the 660 flywheel but this one lost its spark! In order, I would say Key, Coil, flywheel would be the most likely issues. Is there any other history to this machine?

I feel let down?

I am taking it that the screw hole goes straight in to the inner crankcase same as the 372. If so, helicoil the hole carefully and fit a new bolt - may need a little sealant around it to ensure it is airtight.

242XP New piston, clean and lightly hone the bore, pressure and vacuum check and service the fuel system. 346 - just make sure the bore is clean and smooth. Engines cant tell they have small imperfections, they need good compression so the bore above the exhaust port is the important part as long as the plating isn't worn off below it!

Think we have an echo!!!

Tyre put on the wrong way round? Those are definitely alloys so whats with the cable tie? The tyre did shred on that car by the wear on the inner arch. Was the driver pissed and kept driving despite a front wheel blow out?

That is a bit thrash for Stubby, he is more vintage tele or 335.....and so am I for that matter!

Bugger off, I am enjoying my leisure time!!!!!!

The nut that looks like the cover is missing is the lock nut and usually doesn't have a cover!!! The cable tie is bizarre as those are alloys and have been well kerbed a few times! The wing is also dented - bad driver???

Probably worth stripping and selling the parts as this can be more lucrative then refurbishing if that is your thing. GK knows his mowers, sound advice!

Take an old plug, bend the end electrode out at 45 degrees or take it off completely then place it in the cap, earth it and pull the saw over hard and fast. If it sparks - there aint much wrong with the flywheel or coil! I wouldn't get too hung up on these parts unless you have no spark, the saw has strange cutting out issues or fails when hot.

There is a Stihl document on which flywheels and coils go on which machines. The flywheel part code is, helpfully, on the back of the flywheel!!!

Glad the Husky is working well?

I haven't really had a look at the oil strainer on these machines as I haven't had one in with issues. Technically, the strainer is there to stop dirt blocking the pump. Taking out a strainer may work for a while but it will allow the pump to become blocked. I would look at seeing if the Stihl or Husqvarna strainer may fit and work better. I wouldn't recommend removing the strainer on any saw as it is likely to cause further issues in time.

You called....feeling like a bloody genie!!!! Pump shafts typically run in an alloy housing or in a metal insert pushed in to a plastic or metal body. Sometimes after many years use, the metal, especially in the alloy ones, gets a bit worn so the oil isn't pressurized through the pump properly and can end up pissing out between the shaft and housing out where the pinion fits - it happens and can severely reduce oiling pressure - seen it on old 020Ts a fair bit. The pump typically gets plugged with wood chip as the filter tends to be pretty course, pick up pipes or filters can get blocked and also bar holes can be blocked - seen it all before. I usually just strip the pump out, check for plugging, check the pinion, check the pickup parts and flush the tank. That fixes most issues apart from excessively worn pumps.

If starter timing is a bit out, the saw will be wrenching your starter handle out of your fingers - it can be made easier!

Magneto - like on those French mopeds? Couple of things, when the saw coughs on full choke, when you knock the choke lever up one notch and it does get going, does it just idle or does the engine rev up on a 1/4 throttle speed? If he engine just idles on what is the fast idle setting (one notch up from full choke), it will be the control shaft - the lever that holds the throttle open often breaks off these early machines meaning the fast idle setting isn't there. The other thing if this lever is OK is that often the low speed adjustment is a bit lean making starting cold pretty difficult. Richen it up a bit, increase the idle and bingo.

Same system on the 572XP. The design cuts down on the width of the saw as the point of seal is on the bearing rather than a way down the crank hence it being used on many saws. Many 346s I have done have needed this seal replacing, much more so than saws of similar age of different design.

Pressure test the fuel line or just replace it. It sounds like that the carb draws in air through a split or hole in the line once not submerged in fuel - most likely reason! It may possibly be issues with the pump diaphragm or shyte in the gauze strainer but the level of the tank shouldn't effect these issues.

That's not very good. The seals push in to the bearings same as the 346, 576, 560 etc. I can't say I like the design as I find that the thin seals don't last as long as ones pushed in to the crankcase that are further away from the heat and fluids from the bearing. Saying that, the 660/460 seal design (pushed in to the bearing clutch side) with a much larger seal seem very reliable.....and cheaper! Very strange that the seal is leaking after such a short time - pretty easy manufacturing job to push the seal in to the bearing correctly.

I just use High Temp Lithium grease. Does the job!

That's strange, I have seen twisted cranks before and the output shaft wobbles when rotated due to the twist but it is rare, one 346 and can't remember the other machine type, think it was a 660. Let us know what you find.

Probably different sets of coils and flywheels. Had that with a blower once, the thing sparked when the magnets were around 180 degrees from the coil. Check to see if there are two types available. Highly unlikely the crank has twisted.

Nice?

It isn't like the Stihl unit where you can just change a small solenoid. The usual method of fault finding on these saws is to see what fuel the AT unit is giving the saw and then diagnose what the fault may be. If there is a big air leak, the AT unit will adjust the fuel to be rich to cope with it. If the saw is holding high revs on idle, I would check the throttle linkage and the tightness of the cylinder bolts to start with. And go from there. Strange a new coil and carb didn't work and can see why the saw is being pressure and vacuum tested now. Any new carb needs to be programmed with the CST software and then set to the machine with 5 mins flat out running!