small engine -- no oil

I've been doing small engine work for a few years now. I had a customer drop off a tiller this AM and he said he ran it down a row yesterday and then he left it idling while he did something else. It cut off and neither the battery starter or the pull starter will turn it over now. He said the battery had been weak and I hoped the pull starter was just jammed. I remove the pull starter and it's completely fine. I checked the transmission clutch and found it was engaged so I put it in neutral hoping it was just stupidity. No go. I finally got a 12" breaker bar and socket on the nut under the pull starter and with that was able to turn the engine with some effort. So I checked the oil dipstick. Nothing! In an effort to see just how low it was, I drained the oil and got maybe 2 oz out of it. It looks like it probably is supposed to hold 20oz. At this point I think it's fairly obvious it was running with insufficient oil and has seized/partially seized as I can turn it now with considerable effort using the pull starter--it will not spin and I doubt I can pull it fast enough to start it.

Is there any point in doing any more? Should I tell the customer the engine is shot or give them any hope that with new oil and a lot of turning perhaps it'll loosen up enough to start and with running free up any more? At this point I probably will not charge anything but if I have to spend more time I'll have to charge. Frankly I'm not sure if it would free up any or not. Rebuilding the engine may or may not be feasible as I don't know what a mess has been done inside and if it's limited to the main bearings, the connecting rod bearings or the piston and cylinder. I can replace parts but I'm not set up to resurface cranks or hone cylinders etc. I'm sure this customer will accept running--even if it's smoking heavily if possible.

New engine, no sense messing with the old one.

it is likely toast, but you can fill it with oil and see what happens and only be out the cost of a qt of oil. Sounds like that is what the customer is going to ask you anyway so may as well answer that question now , and you can keep with the no/ minimum charge , then depending on what they want to do with it , figure what needed repairs will be.

I'd tell him up front. It might run again, but will never be the same. Best way would be over haul itm or replace it with a new motor.

Put one of those Harbor Freight engines on it. Cheaper than a rebuild and they are good engines.

I believe you answered your own question.. Any engine that has been run with no oil and locked up is pretty much ruined. Oil is the life blood of a engine.

Chris,
Pour a few drops of oil down the spark plug hole,leave the plug out. Grab a 1/2 heavy reversible drill with a socket that fits the starter nut, crank away until it gets easier,and it should. when easier,insert plug and try to start,hope this works out for you.I've done quite a few.It doesn't always work, it depends on how bad the rod and bearing surfaces are bunched up on the crank. We've even added STP and cam break in lube to the engine oil to get it freed up, just remember to drain and refill with plain oil before giving it back. Did this engine have the low oil sensor on it to help save it?People should really go over a unit before using it, a lot of them don't. We do, hope this helps.
Regards,
LOU

I don't have a drill that would touch turning it even if I could get it mated to a socket that large. My impact wrench might spin it. It does take some effort so I'm not sure if it'd spin it or just turn it. I guess there is little to loose so I'll try.

Agreed. I put one of their "Preditor" engines on my old Wheel Horse Tiller - I was surprised how weak the old HH60 Tecumseh had gotten in comparison.

I say put some oil in it and give it a whirl.

Back in high school small engine class one of the guys wanted to see what would happen running one out of oil. It was his engine and teh class objective was over. Drained the oil and it ran maybe 5 minutes till it seized. The next day it was free enough after it cooled to run again. It was just bolted to a bench so not sure how much the power suffered.

I agree on filling it with oil, and see what happens. I hate to admit it, but I ran the 8hp Tecumseh on my splitter out of oil. I filled it with oil and let it cool, and it started. Smoked a little, but it ran for another ten years
Pete

I had 5HP B&S on a plastic pump, pumping liquid nitrogen fertilizer. The seal went, and when the engine quit, I discovered it was because the fert. had pushed through both seals and filled the crankcase with sludge.
The most I took off the engine, if I recall correctly, was the little valve spring cover. Otherwise I flushed and cleaned. At some point, it didn't want to turn over, and felt like it was grinding. But I persevered, and eventually got it going again. That was years ago. I still use it.
If you're going to mess with it. You might want to over fill the crankcase at first to get lots of lube up around the crank/rod area.

definitely an idea. I hope the shaft and mounting dimensions match. This is and old Troy-Bilt Horse tiller made by Garden Way (pre MTD).

If it was on your own machine then messing with it and adding oil if it lived with some careful use then that's fine.
Now for a customer NO WAY ! He ruined the first engine and will never be able to keep it alive if it even would live to die another day. Then you may be bad mouthed.

In that situation If I was going to even try, I would recommend Slick 50 or similar and or Lucas Oil Treatment, he may get lucky and it loosen up enough to run...

Don't use an impact on it, it will over tighten the nut! An impact puts out short bursts of very high torque, not smooth rotating force like you need.

Ya,I skrewd up a few years ago and thought I ruined the 4 horse Briggs and Stratton on my power corn rake. It wasn't dry,but I had it at quite an angle in the corn crib when it seized right up. I pulled it out on the level,filled it,let it cool and put a pair of vise grips on the end of the crank out beyond the clutch. I worked it back and forth a little when it cooled,kept at it until it went all the way around. The darned thing started right back up and still runs,no lasting effects.

Yea, that's my fear but I don't have anything else that'd turn it--not sure the impact wrench would. But like noted the engine is pretty much worthless anyway. I'm going to try the starter first to see if it will turn it over now that I've got it moving by hand. But I can't let that churn at it too long either as it'll get hot and go bad.

The rod has been siezed to the crank from lack of oil. The crank will have deposits from the rod, and the rod cap will have stress cracks in it. It might run for an hour, but it will disintegrate the engine..

I did that many moons ago with a a 350 Honda M/C. I loaded it up an took it home. The next day I filled it with oil and rocked it back and forth and it finally came loose. I fired it up and all was well. TDF

I purchased a new Briggs one cyl. years ago that was started with out any oil and ran for bit and locked up.
All it needed was a new rod. Crank and the rest was fine. If it was mine I would take a look.

2 main friction points on a engine- the piston/cylinder wall area and the connecting rod to crankshaft bearing area. Next close in line is the main bearing area, followed by the valve train. The seizure of small engines cause varies some- but the cylinder wall/piston area tends to seize first with low/no more oil failures at moderate speeds. Con rod to crank failure to lube symptom at high speed is usually not a "seizure" but a snapped rod banging inside or through the cylinder wall- a "blown" engine. Helpful to know the engine involved- did it have a oil pump or splash lube? Whatever- couple small engine shops, chainsaw shops and moped shops that got the run without oil in premix and the "forgot the drain plug after oil changed" for 4 strokes have roughly 2/3 to 3/4 stopped engines with piston and cylinder wall seizure but still safe con rods and crank bearings- especially upright cylinder engines. The lack of lube affects them first and overheating piston rubs hard on cylinder wall and "seizure" occurs. SO, better than 1/2 the time a top end repair or correction will get the low lubed engine back in service- knurl piston skirt, fresh rings, crosshatch bore for the fussy racers. For the economy special- top crankcase to recommended level, add a couple tables spoons of oil to top of piston through spark plug hole ad let set a hour to let oil trickle down around rings- a couple shots of WD40 or PB Blaster first in spark plug hole helps according to some mechs- and slow turn 5 to 10 turns before putting spark plug back in and trying to run. The oil in plug hole and couple slow turns is normal in Wisconsin for over winter stored various engines- 50 weight racing oil in cylinder will get some stuck rings sealed some at first start attempt. If you have a fiber optic cable/bore light you can look inside cylinder without pulling head, note scratches on cylinder wall, chips on top of piston. Oil up top of piston/cylinder, do the slow turns and listen for rod rattle, put plug back in and hand turn couple cycles to "feel" compression and then try ignition. More likely to run with some smoking, lessor chance of quick rod failure but still a possible. Customers choice, give fair warning and note the Harbor Freight 6.5 engine often on sale for $99.95--but full price of $129.95 saves a lot of rebuilding time- usually only a hours labor to swap. RN

Through the years I have had two or three engines that were locked up due to lack of oil that I was able to free up and they ran OK. You just never know until you try. Me, I'm just curious enough to fill it with oil and see what happens, if there is much damage,it will knock pretty badly. I have read that muratic acid will dissolve aluminum deposits on the crank, I know lye will, but you have to be careful with it. If the crank will clean up, you may get by with replacing the rod. Kinda depends on what the the customer wants to do,too.

I put some motor oil in the spark plug hole while eating lunch. Filled the crankcase with 24 oz vs the 20 it should have. Plug removed the starter wouldn't turn it. The impact wrench was disappointing as well as it was obvious in 2 seconds that it wasn't going to spin the engine. Surprisingly to me my 3/8 air ratchet spun it quite nicely although it was a bit abusive to my hands holding the wrench. Still letting that spin it for a few minutes had it feeling better. Now I attached jumper cables to my truck (he noted the battery was low) and now the starter spun it and it started right away. I let it run 30-45 minutes.

I called and left a message for the customer to contact me. He dropped by and I explained it was locked most likely due to low oil. I showed him the pan with the tiny puddle of oil that had been drained from it. I noted I'd managed to free with a wrench and get it turning freely enough to start etc. I warned him it might or might not continue to run acceptably and I couldn't guarantee anything as I didn't know how bad the damage inside was. I explained that it probably would burn oil now even if it hadn't been before. I told him I was going to change the oil again to drain any metal shavings breaking it free and letting it run and "break in" again might have caused. He seemed quite fine.

I'll just charge him for an oil change.

Thanks to everyone for the advise.

Using an impact on a flywheel nut can cause over-tightening. Over-tightening can lead to a cracked flywheel. A cracked flywheel can lead to shrapnel when it explodes.

On the final oil change, you may want to add some Lucas oil treatment, I have had it do amazing things for me, worth a shot. Good to hear it is at least running, for how long none of us know.

Fixed A Briggs & Stratton for a neighbor that ran dry of oil due to a loose oil filter. Rod seized to the crank. Polished the crank, new rod, new rings, it's still running 12 years later.

A couple people have indicated they replaced a connecting rod and/or crank to fix an engine. Isn't that very expensive?

20 years ago I bought a non-running tiller and upon getting it running it ran 2 minutes and slowly spun to a stop. Crank pulled with 0 resistance. The connecting rod had broken but didn't damage anything else. I could have bought a new engine for what it would cost to replace. Thankfully for me back then the local scrap yard threw all their old lawn and garden engines in a big pile and let people pull them apart and scrounge through them. I opened several that looked like mine before finding a match and bought the whole engine for cents per lb. I wish they still did that but I can see why they don't.