I'm at a loss.. please help.. Stihl FS450

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Thanks heaps for the offer - I'm pretty sure shipping to Australia will be cost prohibitive. I've also replaced the shaft, the gear box, the carby, the cylinder, the piston, the crack shaft and con rod, the bearings. by now i may as well have bought a new one :/
Np I haven't shipped internationally for a while so u may be correct.
 
does it pop if you spoon some 2t mix down its throat, dont use start ya bastard canned stuff it has no oil in it.
if it does, your looking at fuel delivery issues, we will sort it, just need to methodically work thru it, in the end you will know more about it and have a working unit.
 
Don't pay for labor. There is more available knowlege on this site than you will find at a single repair shop. There are guys here who have brought saws back from the grave.


Throw a tablespoon of mix down the carb. You'll likely get a bit more run time from that then you get from starter spray. The slightly longer run time will give you a better indication of whether or not the timing is correct (which it most likely is).

It does sound to me like you have a fuel delivery problem at this point.

does it pop if you spoon some 2t mix down its throat, dont use start ya bastard canned stuff it has no oil in it.
if it does, your looking at fuel delivery issues, we will sort it, just need to methodically work thru it, in the end you will know more about it and have a working unit.
OK, i put some fuel (about half to 1 table spoon) down the carby and it did pop a bit, better than with the starter spray, but still not for very long.

The primer bulb works and will fill the carby then overflow down back into the tank, if that helps.
 
So did it start, sort of run, rev a bit then once the fuel was consumed, stop ?
when you first try, its like its flooded, then runs, then goes lean.

if it does that, then you know your spark side of thing is sorted and ok.

any chance the fuel lines are put on backwards ?
not being a smart arssse, just trying to step by step thru this so you dont leap frog over it.

check pm, give me a ring if you want, can talk a bit more thru it if that helps.
 
So did it start, sort of run, rev a bit then once the fuel was consumed, stop ?
when you first try, its like its flooded, then runs, then goes lean.

if it does that, then you know your spark side of thing is sorted and ok.

any chance the fuel lines are put on backwards ?
not being a smart arssse, just trying to step by step thru this so you dont leap frog over it.

check pm, give me a ring if you want, can talk a bit more thru it if that helps.
yeah, first few pulls nothing, then 1 spark, then a few sparks, then it ran for about 1 or 2 seconds then stopped, then nothing (as i assume it was out of fuel).

Fuel runs in from the bottom of the carby, out through the top next to the adjustemnt screws, into the bulb, then out of the bulb and back into the tank.
 
Hey guys, time for an update. I finally had time to take it apart again and it looks like either I put too much grease on the bearings, or have load on the bearings, as it doesn't want to spin. But here are some photos of taking it apart if anyone is interested.

DSC_0545.JPGDSC_0546.JPGDSC_0547.JPGDSC_0548.JPGDSC_0549.JPGDSC_0550.JPGDSC_0551.JPGDSC_0552.JPGDSC_0553.JPGDSC_0554.JPG
 
That base gasket will need replacing too, see its torn in the 2nd last pic at 3 O clock.
is it the original gasket, looks like its blocking off some transfer ports too ? not sure if the ports start in the case halfs, or if they are above the gasket.

just looked at an online parts list, and it shows the plain gasket that you have, and no ports in the case halfs.
 
Ok, status update.

After spending many hours with @trains I have torn it right down and cleaned out the heavy grease that I put in there, out the bearings on using the correct method, used the right lube, sealed the crank case (which was not done last time), put new grease seals in, put the crank case bolts in (as I seem to have forgotten to do that last time..), and discovered that the Chinese carb was terrible.

Here is it running with the original carb on it



And now here is is after reading down the carb and cleaning it all up and putting it back together.



I'm very happy with this, and will look to get a genuine adjustable carb.

Thanks again to @trains - I really couldn't have got this far without your help.
 
Ok, status update.

After spending many hours with @trains I have torn it right down and cleaned out the heavy grease that I put in there, out the bearings on using the correct method, used the right lube, sealed the crank case (which was not done last time), put new grease seals in, put the crank case bolts in (as I seem to have forgotten to do that last time..), and discovered that the Chinese carb was terrible.

Here is it running with the original carb on it



And now here is is after reading down the carb and cleaning it all up and putting it back together.



I'm very happy with this, and will look to get a genuine adjustable carb.

Thanks again to @trains - I really couldn't have got this far without your help.

You’re in very good hands with @trains. Having been a professional mechanic spanning many different fields including aviation and racing and now a full blown chainsaw nut, I’m forever picking his brains. If it wasn’t for him teaching me what he has and continues to do so I wouldn’t be able to have repaired the countless chainsaws, strimmers, edgers and now small Villiers. Glad you’ve build up a friendship, wonderful to see his guidance once again has been invaluable. I’m just waiting for him to start charging us, or not answering his phone :laughing:

AB7148A5-948A-4BB2-8A99-4D6B23E7902F.jpegE5AA0B4B-0116-4743-A5B6-C689BDD03BFD.jpeg
 
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