Thread: Chainsaws again

If it is a new one, maybe the safety feature won't let it start unless you are wearing a helmet, face shield, gloves, boots and chaps

I always try the old capful of neat petrol down the plug hole. Normally works.

The fuel mix could have had the volitile agent evaporate.

CC

It is best to only make up the fuel you will need as even though they say it doesnt, 2 stroke fuel will go off.

Did you use a good quality synthetic 2 stroke mix or just engine oil to make the mix and did you use high octane or standard Ulp.

In my experience you are best to use Pulp and Synthetic motor bike 2 stroke oil but again, mix it up at a litre at a time unless your going out to do a big job and will use the whole 4 or 5 ltrs.

What brand is it?
How old is the saw?
Whats the comp like?
Does it have a decomp valve which could be stuck open?

Hope this helps and knowing the rest of the info would help diagnose it easier

Originally Posted by Casper

It is best to only make up the fuel you will need as even though they say it doesnt, 2 stroke fuel will go off.

Did you use a good quality synthetic 2 stroke mix or just engine oil to make the mix and did you use high octane or standard Ulp.

In my experience you are best to use Pulp and Synthetic motor bike 2 stroke oil but again, mix it up at a litre at a time unless your going out to do a big job and will use the whole 4 or 5 ltrs.

What brand is it?
How old is the saw?
Whats the comp like?
Does it have a decomp valve which could be stuck open?

Hope this helps and knowing the rest of the info would help diagnose it easier

Thanks for that. Don't laugh but the saw is an old McCulloch SP81...around 30 years old.Has not done a great deal of work over its life and as I said, was working fine a month ago. Yes it has a decomp valve that I'm sure is working fine and comp is OK. I am using and have always used standard unleaded, mixed 50:1 with Husky 2 stroke oil.

Try changing the fuel, it can make a big difference to 2 stroke engines, but one month old shouldn't be too bad.

Also, remove the spark plug and re-connect to the HT lead. Hold the threaded section of the plug against the block and see if there is a spark when you pull the starter cord - it'll be easy to turn over with the plug out - don't zap yourself! No spark could be plug, plug lead, magneto or start/stop switch or switch wiring.

If you've got a spark, my guess would be a blockage in the fuel system, probably the filter, which may well be in-tank.

Jon

All the tree contractors that work for me tell me they use this method and it works for me.

Turn choke on and pull cord to start. When it kicks, even if it does not start turn choke off and then start. May take a few pulls to get going but it always starts.

Works on my Stihl every time.

Or you could get Sandy to buy you a new one for your Birthday.

Aerostart

Time for a new saw, cranky saws are a pain

Fuel "should" be fine, I leave mine in for months, never had a prob, I use PULP and Husky oil........not to say it should be discounted as the problem

Originally Posted by Chenz

All the tree contractors that work for me tell me they use this method and it works for me.

Turn choke on and pull cord to start. When it kicks, even if it does not start turn choke off and then start. May take a few pulls to get going but it always starts.

Works on my Stihl every time.

Or you could get Sandy to buy you a new one for your Birthday.

That's the method I've always used with 2 stroke stuff, only this time it aint working.

The lovely Sandy has been sounded out........but........no joy at this stage.

Originally Posted by numpty

Damn thing wont start. I put a new plug in it a month ago and had it running on and off over a few hours with no problems. Wanted to use it today and no go. It will kick first or second pull, but after that....nothing. Removed and cleaned plug and let chamber dry out for 10 minutes or so, then same thing, will kick once then nothing. The fuel mix is a month old, could this be the problem?

Over to the gurus.

depends on the type and how old the saw is... but most owners with saws which have walbro type carbies rarely service them and there can be problems from the fuel pick-up on through the system... most chainsaw places have diaphragm/carbie gasket kits to enable you a thorough cleanup type rebuild

(this is for when pouring a few drops of fuel down the plughole doesn't work anymore)

hope it helps