OutdoorKing Repair Forum Forums Restoring, Customising and Modifying Tech Talk To Run the Fuel Out.....or Not ?

Hi to All,
Here is a question that I often hear mentioned (and always some friendly debate) when discussing Victas mainly.......Do you turn off the fuel tap and run the machine till she runs out of fuel.....or just shut it down and then turn off the fuel tap?

Another thing I have always wondered, I suppose there is the chance you could cause some premature wear on the cylinder, etc by starving it for the fuel/oil mix. But I usually run them dry lol.

drjbeam I agree that Darryl should have put a poll in his question he asked.

So here is your poll below.

Should You Turn The Fuel Tap Off single choice

Yes (86%, 25 Votes)

No (14%, 4 Votes)

Total Votes: 29 Voting on this poll ends: 0 seconds ago

I just turn the tap off, unless it's long term storage then I would run it dry, remove the plug put a little oil in cylinder.

cheers gmax

To Bruce and drjbeam,
I agree with the poll, but , mainly, I was hoping to hear the "reasons" behind their choice... (viz a viz: Joes and gmax's replies)

lol mine wont start again if the tap is left on

Hey emmo, good to see ya back posting again, mate, have you got any new projects on the go?

emmo glad to see you posting again, maybe you should check what the poll is saying which might help you.

Hi to All,
Just to throw the cat amongst the pidgeons, the poll seems to be showing a convincing argument for 'turning OFF the fuel tap and RUNNING till she stops.'

Here is a direct quote from the Victa Tilt-a-Cut Manual from the Parts and Manuals area:

" TO STOP ENGINE
To stop engine at any time move throttle lever to "STOP" position. This will immediately operate the cut-out switch
in the ignition circuit and the engine will then stop.
At the conclusion of cutting move the throttle lever to "STOP" position and turn off the fuel. IT IS NOT RECOM
MENDED THAT THE ENGINE BE RUN UNTIL THE CARBURETTOR IS DRY AS THIS LEAVES THE ENGINE DRY AND EXTREMELY HOT AND CAN ONLY LEAD TO HARD STARTING.
After the engine has stopped, set throttle lever to the "GRASSCUTTING" position before folding the handles or
before storing the edger to avoid undue strain on the throttle cable."

That's Victa's recommendation, what are your thoughts?

Darryl,

I agree with the part about the throttle cable because many of the Victa's cables pull out of the plastic carbies if you don't put the throttle control down when folding the handle down.

But if you leave the fuel turned on in the Victa's the engine will tend to flood.

When you want to restart the mower all you need to do is turn the fuel on and alow about 30 seconds for the fuel to fill the carby bowl and pump the primer about six times instead of the three times suggested.

With the old Victa mowers it was better to run the fuel out because if you left the fuel in the carby (for a long period) and it dried out you would get a powder residue left in the bowl, hence the jets would get blocked and the mower would not start.

Hope that this is explains why.

Bruce,mate, I think you're on the wrong train!! Your focussing on the wrong point.....I would never leave the fuel on. The fuel tap is usually turned off after mowing regardless....the question is about running the engine dry...that is the debate....not the fuel tap position. Victas' recommendation for the Tilt-a Cut is you do NOT run the engine dry; with an explanation above....What's your thoughts?

If I was not going to use my 2 stroke mower/chainsaw for longer than 6 months I would let it idle until it was dry, then remove the plug & put a little 2 stroke oil in the cylinder.
Pull the starter to distribute the oil,then put the plug back in.

By the way ethanol blended fuel should not be used as it attracts
moisture, (I read that in a Ryobi manual)

cheers gmax

Darryl,

As the unleaded fuel eats into rubber when left because of the Alcohol I would still run the fuel out until the engine stops. I have been doing this for many years now and will continue to do so.

It is up to yourself what you do.

Hi Bruce, you've raised a very good point there, I tend to forget that fuels have changed a lot since some of our machines were built...eg: Regular, Super, where now we have Unleaded, Premium Unleaded and Ethanol blends.....
That raises another question.....With the older 2 strokes, should we use a fuel additive with Unleaded?

Hey Wayne, that is very good advice, particularly for the end of the season.

With a two stroke, if you turn off the fuel tap and leave fuel in the carburettor, over time the petrol will evaporate and just leave the two stroke oil. This oil will often end up blocking the carburetor jet. When you turn the fuel on to start the mower, it will take quite a while to dissolve the oil that is blocking the jet. Hence hard starting is more likely if you do not empty the carburetor. FWIW, Ryobi's whipper snipper operating manual says always empty the fuel tank, then restart the engine and run it until it stops from lack of fuel.

Hi All

Sorry to revive a bit of an old post here but I do let the Victa run Dry
(turn tap off)

Found the two posted reasons as to why, and the counter from the vita manual as to why not... interesting Thank you

The victa mostly always would start first pull & if not and sitting for awhile on the second or third

The reason I do was cause my Father always did
maybe he told me why at some point... long since forgotten

He was I guess a bush mechanic (a lot these days think thats a bad thing) & from the era of you warmed your Engine first before you drove anywhere..days of Holden greys and reds and before

Me I nursed this Vita 2 stroke along as best I can in my ignorance of engines but now think it needs a good over haul which is how I found the forums.....(wondering if I am actually capable of doing it)

The fuel Question is another good point and one I have been wondering about my self...
from what I know (or think I remember it was) the lead acted as lubricant...whether this is important or holds true for a 2 stroke I guess is the question.....as in really required for the cylinder & piston...considering the use of oil ?

The ethanol point is interesting too and
I would have thought not a good thing for the motor

but I could have this wrong ?

Anyway just my 2 cents worth and thoughts ..well from the little I understand of Engines, Thank you
Cheers

Hi Deejay59, welcome to Outdoorking.

Like some other engine manufacturers, Briggs and Stratton recommend emptying the tank and running the engine dry before storage, or if the storage is only for the winter season, adding fuel stabiliser to prevent water absorption and gum formation.

The main mechanical benefit of the Tetra-Ethyl Lead (TEL) in old-time petrol was that it decomposed into metallic lead during combustion and the lead tended to coat the hottest parts of the valves, substantially reducing wear to valve guides and valve seats on 4 strokes. The TEL did far more harm than good mechanically however. The lead it formed tended to short-circuit the spark plug, so extremely chemically active chemicals, known as "lead scavengers", had to be added to the TEL to limit that problem. The bromides and halides the scavenger produced after combustion then ate the exhaust system. Have you noticed that exhaust systems last more or less indefinitely these days, compared with five to ten years in the old days? And of course spark plugs no longer require periodic cleaning.

Lead may help to lubricate the piston rings in 2 strokes, especially when crossing the ports, but I haven't heard of it having significant effects. Essentially, TEL was a desperate move invented in the days before catalytic cracking was used in oil refineries, in order to raise octane levels. Without TEL, uncracked and un-hydroformed gasoline was very lucky to reach 60 octane, so compression ratios had to be so low that fuel economy was appalling. With modern refining techniques a reasonable yield of petrol can be obtained at up to about 90 Research octane. Of course given the chance, refiners will still dope the fuel with octane improvers so as to produce more petrol and less kerosene, but I wouldn't hold my breath waiting for them to get permission to put appallingly toxic substances like TEL in the fuel again.

Lead may well have aided lubrication in a 2 stroke engine but i would think that by now the formula for 2 stroke oil would have been modified to compensate if the lead did indeed make a noticeable contribution.

Its always been the added oil that does the lubricating, back in the Super fuel days i never heard of the oil helping the lead or vice versa.

Thank you grumpy & Rodeobob

wow that was quite an in depth reply & informative too from both of you
my thought was more so the fuel of the day.. when the motor was designed and made..as I said ..just tib bits of thought from limited knowledge
in how best to care for a 2 stroke
(yeah maybe that old saying a little knowledge is a dangerous thing )
I didnt know of it power boosting action (or had forgotten)
so guess you learn something new every day

on the oil lead thing Rodeobob
I was more thinking of the effect from it no longer being there
seems it doesn't overly factor in...if it did at all, oil mostly does what I was thinking of (lubrication as its purpose...) seems that wasn't its main purpose anyway and from what you say, if it did it was probably compensated for by later oils formulas
Still regardless
lead its not a good thing to have floating around either so good riddens it seems on more then one count...

Thank you both Cheers:)

time for some more reading