Printable View
Don,Quote:
Originally Posted by Don 130
Seems to be a problem with any petrol powered item that is used infrequently. Makes you wonder what the difference is with petrol nowadays.
The stabilisers seem to work for up to 1 year. Anything longer and you need to drain the fuel and re-fill.
I've also had problems with old fuel turning into varnish. Fuel pumps on two of my Land Rovers kept stopping, the varnish was sealing the valves shut !
Colin
The problems with modern petrol seems to be twofold. Firstly, virtually the entire petroleum industry seems to be infected with bacteria that will grow in fuels (if water is present). This bacteria was probably absent historically over most of the petroleum infrastructure, but once infected is almost impossible to remove. I suspect it was largely controlled by the bactericidal effect of lead in petrol, so it was not a problem.
The problem is exacerbated by the presence of ethanol in a lot of petrol today (small quantities do not have to be placarded). Ethanol is hygroscopic, so even small quantities guarantees that there is some water in the petrol.
John
Two stroke fuel needs to be mixed at the correct ratio as stated by the manufacturer. So many people don't mix it correctly, then when the chainsaw or whatever they are using doesn't run properly, pull the revs, or is hard to start, they go for the screw driver and start playing with the mixture screws. Ninety nine point nine per cent of the time when these engines won't start or don't properly, it's fuel related, stale fuel or incorrectly mixed. Cheers, Mick.
Never use ethanol fuel in small engines which may sit for a bit, it will soon turn to jelly and block everything up requiring a strip down. I don't use the stuff in any engine whatsoever, not worth it.
Ethanol may be present in any petrol sold in NSW - it only has to be labelled if 10% or more. Even small percentages will absorb water! Bigger problem in coastal climates, not as serious inland.
John
A couple of other things that might help. Keep fuel tanks filled to the brim to reduce the possibility of humid air in the tank condensing water into the fuel, or has already been suggested, empty tank and run engine dry if it's not going to be used for a while. Some of our pumps only get used twice a year. Spring and autumn. That is considered too long to leave the carbys empty as the seals and gaskets can dry out and deform if dry for too long.
Don.
Hi All,
The hot 2 stroke non start was covered in another thread about 6 months ago....... fuel probs with diaphragm carbs supposedly, but I've had the same prob with slide carbs going back 40 years. The hot thing has not been answered as far as I'm concerned.
Not all the small two strokes I have (<100cc) do it.
Yesterday I cracked it with the largish Stihl I have, heaps of compression, cold start, 10 pulls and I have a bone broken in the pulling hand. No nothing. Not happy, maybe even swearing.
Got the can of aerostart out of the Howard rotary hoe toolbox, little squirt on the air filter, instant go. That will be standard from now on.
The other saw I use for less than 4" stuff and one handed overhead, a $100 Ross 16" will start from cold after no more than 3 pulls but will never start from hot. Maybe aero is the inverse answer for that.
I have a cheapo brushcutter that will start hot or cold with old or new fuel and it has probably done at least 200 hrs of serious slog. Go figure!
cheers, DL
I was talking to our ex local mower shop owner [now the local glass shop owner and making more $] recently he said the carby diaphrams go hard, they may look ok but they are not working 100% which is most of the trouble with 2 strokes engines.
My 20plus year old McCulloch whipper snipper has always started first go and has never even had a new spark plug.
The shield between exhaust and tank recently vibrated off and the fuel lines rotted once and I had to replace them for $5.
The secret?
When finished ,empty the machine and restart with the fuel in the carby and run until it stops.
Regards Philip A
That was the trick I was told by a mate that owned a small engine shop for 30 years. Works a treat. :)Quote:
Originally Posted by PhilipA