Lawnmower Enginge Storage Method

All of the storage instructions I have seen for small engines, such as lawnmowers, say to take out the spark plug and put in a couple teaspoons of oil, and pull it thru a couple times, then replace the spark plug. I have done that for several decades without a problem. But something occurred to me.

Why can't we just tilt the mower so that the spark plug is pointed DOWN (easy for vertical shaft engines) and then just pull it thru a couple times.??

It seems to me that the oil will run over the bottom of the piston and when the unit is pulled thru a couple times, the oil will wipe the inside of the cylinder, accomplishing the same thing as when we squirted oil into the top of the cylinder....

I would like to hear any opinions on this. Perhaps there is something I missed, but this would save a little trouble , and could easily be done after each mowing operation.....

Andy in Eureka, Texas

Reply to
AndyS
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Sounds like a helluva good idea. Strange I've never heard it before. But then I never bother to put oil in the spark plug hole either - and I'm runnin a bunch of old equipment.

Reply to
Srgnt Billko

Hi...

I suspect that over a short period of time virtually no oil would get past the rings, so there'd be no effect at all.

On the other hand, over a long period of time sufficient oil might get past the ring splits, but wouldn't serve any purpose other than drowning the plug.

Take care.

Ken

Reply to
Ken Weitzel

Because the oil will flow much more freely into the intake/air filter/carb through the crankcase breather than it will past the rings.

Reply to
Art

Huh ?

Reply to
Srgnt Billko

I fog boat engines and oil the plugs, so it does make sense. I've never done it to lawn equipment though. Perhaps I should.

Reply to
Steveo

If the engine in the mower is in any kind of (good ) shape, no oil will flow past the piston rings. And only a small mower could be tilted as you suggest by a man of average strength. Removing the spark plug and introducing a small quantity of oil is a mundane task. But none of this is required after each mowing- only for storage over winter.

Reply to
Chas Hurst

Andy writes: My thanks to all those who ventured a reply here.

I'd like to comment on Chas's reply, which is typical of those who had reservations on this method.

When you put oil in the spark plug hole, only two things get lubricated - 1) Part of the top of the piston and 2) The part of the cylinder where the rings actually wipe. The rest of the inside of the top of the cylinder stays as it was, since there is nothing to wipe the oil over it AND the quantity of oil isn't large enough to slosh ( for good reason).. Wiping the rings coats that part of the cylinder since THAT PART is the part that has wear 6 months later when you crank it up for the spring. Having a little film of oil on that small part of the cylinder wall helps reduce the excessive wear that dry piston rings have on a dry cylinder wall. Remember how the engine lays and where the oil reservoir lies..... Most of the cylinder does not normally anywhere near the oil, and that's OK, since there is no rubbing action on that part of the cylinder....

Also, oiling thru a spark plug hole works much better on an engine whose cylinder is vertical, since the oil will distribute itself all over the top of the piston before wiping. On a vertical shaft engine where the piston is horizontal, only the bottom of the cylinder will be wiped UNLESS you tilt the mower to make the spark plug on top...... Same tilting action as I proposed for the internal wipe, except upside down....... Yall gotta think about what happens inside the cylinder .........

So, in my opinion, it doesn't matter whether the piston rings wipe the ring area from the bottom or from the top.

Regarding the strength to tilt the lawnmore and pull the cord two or three times ---- well, it just never gave me a second thought. I would think that if such strength were lacking in the actor, that he/she would be paying someone to mow their yard anyway :>))))

Regarding pouring oil out the crankcase breather tube --- it doesn't happen in the 3-4 second the mower is tilted. Heck, I tilt the mower longer than that when I'm mowing.... I've never seen it happen..... And , for this operation, there is no internal pressure buildup to vent, to speak of....

Ok, thanks again everyone. I welcome criticism of my understanding of the inside of a mower. There's a lot of guys here I can learn from.

Andy in Eureka, Texas

Reply to
AndyS

On a somewhat related side issue, I do believe it's worthwhile, when putting away a small engine, to pull gently on the starter until you feel compression resistance, and leave it that way, with the valves closed.

Take care.

Ken

Reply to
Ken Weitzel

Andy comments: Now THAT sounds like a great idea !! After pulling it thru a couple times leave it at top dead center.... .... I'm going to start doing that..... thanks.

Andy in Eureka, Texas

Reply to
AndyS

The crankcase has to be vented so it does not build up pressure from the small amount of blow-by that gets past the rings. This vent is part of the valve cover on a side valve engine (most of the small engines out there.) There is a tube or hose that connect this vent to the intake so as to actually create a slight vacuum in the crankcase when the engine is running. When you tip the engine the wrong way the oil flows pretty freely through the vent and then into the intake. Once there it is a major nuisance. It can saturate the air filter, get into the carb and even leak past the intake valve into the cylinder. While this might be good for storage purposes, it's going to be a mess when it's time to get it running again.

Reply to
Art

Gravity takes the oil to the lowest part of the cylinder. Condensation will also head for that same area. You want the oil to get there first to provide a barrier.

Most small engines have a small plastic oil slinger in them that begin slinging oil as soon as you attempt to start it. The storage oil is more to protect from rust or corrosion that can cause stuck rings from moisture than as a pre-lube to reduce wear.

In the cases of stuck rings that I have seen most were caused by carbon. The rest were caused by rust or corrosion and always at the bottom of the cylinder.

Agreed.

3-4 seconds is not going to do anything. I would guess (and it's only a guess) it would require more like a minute or longer to allow any oil to leak past the rings.

If you tip the mower with the crankcase breather down for long, while it is running it will start sucking oil through the breather and smoking heavily.

There is no internal pressure buildup ever. While it is running there is a vacuum.

If you are going to do this then I suggest you locate the valve breather and make sure it is kept as near the top as possible while tipping. Maybe even remove the plug just to see how long it does take for some oil to come out of the plug hole. If you do that, let us know how long it took. I am curious.

Reply to
Art

That is definitely a good idea. Moisture and condensation are bad and if you can leave the valves closed it should keep most of that out of the cylinder.

Reply to
Art

Thanks Art,

As an aside, I stored a boat motor for a couple months with the motor tilted too far toward the plug, and the space in the cylinder filled up with oil from leakage. When I tried to crank it, the oil would not let the piston go all the way. It felt like the engine had seized. Really felt like a hard clunk metal thing..... As a last resort I pulled the plug to see if I could tell anything and the oil ran right out. I put the plug back , and the

problem disappeared, tho it did smoke like hell for a couple minutes....

So now I always store the boat motor with the engine tilted so that it can't leak past the rings into the cylinder head....

Just thought I'd mention it.... I was very pleased with myself when the problem went away :>)))))

Andy in Eureka, Texas

Reply to
AndyS

[....]

just something about the way you said "pleased" has prompted me to share these pictures from my web page concerning a recently completed repair that I'm really really really pleased with the outcome of.

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Reply to
Jim Ledford

Andy writes: Wow !!! Your patience greatly exceeds mine. I would have made a lamp out of the thing..... :>))))

Reply to
AndyS

New additions to my family include a generator and a snow thrower. Have not used the thrower yet, and who knows we could have mild winter. You can store both with stabilized gas in tank. I stored my Lawn Boy,

2 cycle, this way last winter and it came through fine. Did away with annoying problem of having to run engine dry although I did replace spark plug in spring as part of normal maintenance. Frank
Reply to
Frank

Bookmarked it, in case I ever have to change a manifold myself. =)

Reply to
Eggs Zachtly

I gave consideration to doing just that. after a short conversation with my bank account I realized the 30 dollar salvageable salvage yard manifold would make do.

that drill bit saved me many hours of getting the head off and then putting the head back on as well as the cost of all the required gaskets and then the service cost at the machine shop. interesting operational aspect about that bit was, it grinds instead of cutting. to make it work you need to be turning the bit at least 1000 rpm and you got to push with substantial force. doing that to a conventional high speed steel bit will burn the edge and tip right off of the bit.

best 2U Eggs, Jim

Reply to
Jim Ledford

Ya, but it doesn't sound near as good as it would, ramblin across the fields. =D

I wonder how it would do with a hammer drill.

Reply to
Eggs Zachtly

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