Stihl MS290 problems

[spudulike]

This saw is beginning to do my head in! I came home from work tonight, fired her up, began to cut and she died in the cut just as she'd done before I did the work on her! She then refused point blank to start up again!

 

I've just been out in the workshop after dinner, took the bar off and she runs lovely (still won't shut off but I'm not that worried about that at the moment), revving up like a good un and starting on the first pull like she did last night.

 

The only things I haven't done anything to are the clutch (apart from removing and replacing it when I took the engine out), the chain brake and the fuel line, none of which should contribute to this annoying behaviour. I should have a fuel line in the post tomorrow, so failing that, could it be the clutch? If so, I can sort of understand the stalling in the cut, but why won't she start back up?

 

GRRrrrrrrrrr!

 

And yes Spud I have connected the cables to the engine, and it does make contact when I flick the kill switch. Did you take me for some kind of idiot? Ok, don't answer that one... ;-))

 

 

 

Just trying to help - it is a simple circuit that just connects the coil to earth to halt the spark - hope you get the thing sorted......before it ends up in the bin:001_rolleyes:

[H-A]

This saw is beginning to do my head in! I came home from work tonight, fired her up, began to cut and she died in the cut just as she'd done before I did the work on her! She then refused point blank to start up again!

 

Do not take this the wrong way, have you checked it has fuel.

 

I have done it, mended an engine, run it for a bit then it stopped.

 

It would not start until I put petrol in it, easy one to miss.

 

I would trace the grounding wire, simple continuity issue.

 

H-A

Edited October 7, 2013 by H-A

[Aledafis]

Just trying to help - it is a simple circuit that just connects the coil to earth to halt the spark - hope you get the thing sorted......before it ends up in the bin:001_rolleyes:

 

Yes, sorry, just reading that back and it sounds bloody ungreatful, which I'm not at all! On the contrary, I'm very greatful, you've been a massive help!

[Aledafis]

Do not take this the wrong way, have you checked if has fuel.

 

I have done it, mended an engine, run it for a bit then it stopped.

 

It would not start until I put petrol in it, easy one to miss.

 

I would trace the grounding wire, simple continuity issue.

 

H-A

 

Ha! Yes I also did that for a couple of pulls, but realised pretty soon.

 

I've run a multimeter around the earthing circuit and it's all good. ???

 

There must be something straightforward that I'm missing. The annoying thing is that my time is limited to play with her, by the time I'm back from work and spend a little time with the kids, it's too late to really spend much time tinkering with a noisy engine.

[2stroke-ady]

Ha! Yes I also did that for a couple of pulls, but realised pretty soon.

 

I've run a multimeter around the earthing circuit and it's all good. ???

 

There must be something straightforward that I'm missing. The annoying thing is that my time is limited to play with her, by the time I'm back from work and spend a little time with the kids, it's too late to really spend much time tinkering with a noisy engine.

 

Sounds like its your coil! I've had a few over the years, the connection to the cut out terminal must break internally. It almost sounds like someones cobbled together a load of knackered bits and stuck it on ebay!!

[spudulike]

Have you got a compression reading yet, if you havent got a gauge, get the saw with bar, hold it by the starter and then allow it to drop and measure the time the cord goes to full extansion - perhaps someone else with the same model will do likewise but very generally - over 10 secs is good.

 

Take another look at the piston through the exhaust port - you often get a little marking but the ring should have no visible lines on it and the piston skirt only light scratches or clean.

 

It may still be the carb, these seem to be a bit of a bugger on these saws and possibly a longer boil in the US cleaner. You could pre treat the carb by removing the H&L screws and put some carb cleaner down the holes. Make sure you strip the carb before doing this.

 

Remove the gauze filter - quite often these can get blocked up by old fuel - recently had the same MS200T in for this type of symptom - even my cleaner and carb cleaner hadn't shifted a haze of resin from the gause filter - try it - sounds very similar!

 

The kill switch - just check the leaf spring is earthed with a multi meter and then take the recoil cover off and check the kill wire is on the coil and meter between the coil connection and the black wire. If OK, check the resistance of the switch when made, if it is over an Ohm then clean the contacts and re-check.

 

Simple:001_rolleyes:

[Aledafis]

Have you got a compression reading yet, if you havent got a gauge, get the saw with bar, hold it by the starter and then allow it to drop and measure the time the cord goes to full extansion - perhaps someone else with the same model will do likewise but very generally - over 10 secs is good.

 

I'll get hold of the compression gauge again, but the drop test gives me about 8-10 seconds, so not bad I guess, I'll take a proper reading tomorrow night.

 

 

Take another look at the piston through the exhaust port - you often get a little marking but the ring should have no visible lines on it and the piston skirt only light scratches or clean.

The piston looks good, not a mark on it.

 

 

It may still be the carb, these seem to be a bit of a bugger on these saws and possibly a longer boil in the US cleaner. You could pre treat the carb by removing the H&L screws and put some carb cleaner down the holes. Make sure you strip the carb before doing this.

 

I'll have another go at the carb in the US bath, it won't do any harm and may be the answer I'm looking for.

 

Remove the gauze filter - quite often these can get blocked up by old fuel - recently had the same MS200T in for this type of symptom - even my cleaner and carb cleaner hadn't shifted a haze of resin from the gause filter - try it - sounds very similar!

 

I replaced the gauze when I fitted the carb kit, so that's not it unfortunately

 

The kill switch - just check the leaf spring is earthed with a multi meter and then take the recoil cover off and check the kill wire is on the coil and meter between the coil connection and the black wire. If OK, check the resistance of the switch when made, if it is over an Ohm then clean the contacts and re-check.

 

Simple:001_rolleyes:

 

Ha! Simple indeed... :lol:

 

I ran her up tonight again and she ran well on the bench both with and without the bar, but once she touched the wood, she died down almost immediately, loosing power with the chain stalling in the wood. Could it be clutch related? It's just about the only thing i haven't changed by now... The funny thing is that once she dies in the wood she just won't start up again, could the clutch be sticking a little and putting too much strain on the engine to get up to speed? I'm clutching at straws now (pun intended)

 

Thanks for your patience guys, it means a lot!

[H-A]

I am not sure it is the clutch, If you are cutting at wide open throttle, the clutch will not make the engine die, as it will be engaged.

 

There are three possibilities "as I see it", that will make the engine cut out.

 

1. Lack of fuel (carb problem)

 

2. Lack of spark (coil, plug, ignition lead, kill switch problem)

 

3. Crankcase or induction leak.

 

Techs will be able to give more advice, my bet is air leak, what are the crank bearings and seals like.

Chain gets loaded in a cut, play in bearings, allows air past crank seals, engine dies, could be wrong, is there any play in the crank?

 

H-A

[Eddy_t]

Ha! Simple indeed... :lol:

 

I ran her up tonight again and she ran well on the bench both with and without the bar, but once she touched the wood, she died down almost immediately, loosing power with the chain stalling in the wood. Could it be clutch related? It's just about the only thing i haven't changed by now... The funny thing is that once she dies in the wood she just won't start up again, could the clutch be sticking a little and putting too much strain on the engine to get up to speed? I'm clutching at straws now (pun intended)

 

Thanks for your patience guys, it means a lot!

 

No, the clutch wouldn't cause it to die in the cut, sounds like the carb needs tuning, when you put it in the US cleaner, did you remove the carb needle screws? As it sounds like either a blockage leaning the mix too much, or it's far too rich, flooding the engine on restart

 

 

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[Aledafis]

Yes I took the needles out, but it could be that there's still some crud in there. I'll give it another go.

 

At least it's good to know that it isn't the clutch.

 

Thanks!