Outdoor Power Equipment (Lawn Mowers, Snow Blowers, Chain Saws and more) Discussions

Hi, I'm new to this site and hoped that someone out there might be able to solve what I'm sure is a really simple problem. I've got a second hand Husqvarna 357 XP and it's been working fine. Tried to start it the other day, it popped once with choke on, so pulled again with choke off and the engine would not start. Tried several times and then assumed I'd probably flooded the engine. Left the saw for a couple of days but it still wouldn't start. Checked the spark was 'sparking' and it was, but bought a new NGK one anyway. Tried this new plug and the saw started first time. Switched it off put the thing down, went back to it 2 mins later to start work and the engine wouldn't start again!! cleaned the new NGK plug but that didn't work so left the saw again with the plug out for a couple of days. Tried again with another new plug and it started again fine!! Managed to get some work done, stopped the saw to put more fuel/oil in and the same again.... the saw would not start. Any ideas? is the fuel mix too heavy on the oil and that's coating the spark plug? is the carb adjusted correctly? why will a cleaned spark plug not work but a new one will work!!!

Any help gladly received before I spend all my cash on new plugs!! Cheers

Hi Richard

I had the same problem with a saw once. It's a high-end Stihl, and was doing the same thing that you describe. I took it into the saw shop under warranty, and they couldn't find anything wrong with it. It would run for 30-90 seconds and die as if starved for fuel. I thought there was improper venting to the tank or something, so I took it all apart. The problem turned out to be a tiny pin hole in a fuel line. It was allowing air to enter. Think of drinking with a straw with a hole in it. It was replaced and now it's fine.

Could be a number of things with your machine, just letting you know one possibility.

John

Thanks John

Any advise gladly received, I'll have a look tomorrow. I've had a few other ideas.... fuel/oil mix.... ignition module.... carb setup.... there are a lot of possibilities!

You've pretty much eliminated the electrical possibility.  Suggest you focus on fuel delivery and carburetion.  Check to ensure you don't have a pinch or kink in your fuel line.  Ensure the fuel pick up filter is clean and also inspect the fuel tank for debris & water.  Check your fuel container for water & debris also.   Check your air cleaner & carb linkage.  Make sure your choke mechanism is disengaging as required.  If  that doesn't solve the problem, pull the carb and clean it thoroughly.   I know that many do not recommend using a very thin wire to clean passages, but I do.  If your careful, the carb can be cleaned easily without damage.  Follow up with compressed air through all orifices you see.  Be careful to keep track of disassembly of the carb.   There a a number of diaphragms and spacers and there also might be a tiny spring(s) involved.  Take some digital pictures as you disassemble.  It will pay off later.  Inspect your diaphragm(s) for damage.  Look very closely.  All it takes is a pin hole.  Closely inspect the area of diaphragm that is compressed between the fasteners.  That's where most of the wear/damage occurs.  Good luck.