Some will be OK after seizing. Many tho won't. It all depends on the severity of damage done- and rest assured there is some damage done. I've unseized them to get people going and they can suprise you. Fingers crossed. Other than addressing the float valve issue, you're doing about all you can do. At this point de-flood the engine and get oil or what ever brew you want in the sump. Once you get it to crank, be sure that there is actual engine oil in the case. At a minimum drop the bowl of the carb and clean the float valve and inside - best would be to replace the valve. It will smoke badly once it restarts and burns the marvel out.

I do not think it is seized, not if you can move the crankshaft. Remove the spark plug and insulate the spark plug wire so you will not get a spark. Turn the motor as fast as you can to blow the gas out of the cylinder. Add a thimble amount of motor oil to the cylinder, through the spark plug hole, and turn the crank slowly to distribute the oil. Drain the motor oil and replace it with clean oil

I suspect the carb leaked old fuel into the cylinder and crank case until it could no longer run. See if you can get it to run again. Find out what the noise is and fix it.

You don't want to turn the engine until you get oil in the cylinder (your idea of using Mystery Oil is a good one) and drain the oil/gas out of the crankcase. I'd refill with regular oil, replace maybe 8 oz. of the oil with Mystery Oil this time. You'll have to do another one or two oil changes anyway if you get it turning to make sure you get any filings out of the crankcase.

You don't have to wait days. Leave the plug out, after a few hours try pulling it through. With a little luck it will turn free and you'll be back in business. Make sure you fix the gas leak first.

How does the output shaft of the engine connect to the wheel drive and snow blower drive?? The metal screeching sound and subsequent difficulty in "turning" the engine might be due to something in the "power train" other than the engine. As for the "smell of gas" in the engine oil, consider what you stated in your opening post. You have been working on it to get it started and running, BUT you have "only run it for short periods, 5 minutes at a time". While you have been working on it you have been putting gasoline into the cylinders and up to the point that it fired up.......none of that fuel has been burning, so it has had ample opportunity to leak past the rings and into the crankcase. Additionally, the little amount of time you actually let the engine run would not have heated the crankcase oil enough to "drive out" or "boil off" the gasoline that got in there. You might indeed have a leaking float needle valve but don't use the "odor of gas in the oil" as the sole determination at this point in the game. Check the components that deliver the engine power to the wheels and make sure something there is not seized or locked up before you devote all your time to the engine per se.

Thanks for all the advice.
Yes, indeed I have certainly squirted gas directly into the sparkplug hole as well as pulled on the starter many times with the choke on. And yes also about not running it a lot to get the crank oil hot - when it failed today the oil was warm but not hot. So, its safe to assume that the percentage of gasoline in the oil has been increasing over the past weeks while I have been testing this engine.

I will double check that the engine is fully dis-engaged from the wheels and the PTO. There is a clutch and other things to look at.

The oil I drained out was definately less viscous than normal, it was almost like anti-freeze in consistancy and it was only warm not hot. But even so it felt 'oily' between my fingers. Is it possible for a mixture like this to NOT have enough lubercating properties to keep the engine from seizing? I'm not familiar with this situation so I just dont know. I'll let you know when I can confirm that the drivetrain is 100% dis engaged from the motor.

Tim

If the oil felt "oily" on your fingers, and keeping in mind that the engine was not hot, and was essentially running in a "no load" state.....I would say there should have been no reason for the engine to "seize". About the only reason I can think of that this engine would have seized would be if the fan shrouding sheet metal were completely packed full of mouse nests or something else blocking the fan air volume. Maybe you should elaborate on the "other issues" you referred to in your opening post (just in case there might be some general clues). It is also possible that the engine has been seized before and just did not live long after it was revived.

Sounds like the carb float stuck in the open position, allowing fuel to fill the sump of the engine.
Yes, diluted oil, when cold, will have the consistency of permanent anti-freeze, and though it feels oily, it isn't thick enough to provide proper lubrication and cooling of the engine parts! If you drain hot oil out of an engine that has been running for a while, the oil will be thin. And, if it is laced with gasoline-yes, it will damage the engine!
Mownie has some good advice, so take it. And yes, do clean out the engine air shrouds. And, use 30W oil in it, at least until you get it running correctly. I don't think 10W30 or 10W40 would be good for it. The B&S manual reccommends 30W oil in the engine. If you get it to run right, and feel that 10W30 might work, use it, especially in zero conditions. And, check for debris in the shrouds.
If you do fill the sump with enough oil to cover the connecting rod, drain some out, down to the full mark, when you try to staart it.

I disagree on no reason to seize, only because of a tech snow blower i had, with 6 hp. this blower was almost new, but sat for a couple years in a garage before i got it, the owner had a heart attack and then on hired someone to plow his snow,he used it only one winter a couple times.
anyway when i got it, i drained oil and put in new, turned it over till oil ran up into cyl. cranked it some, and drained it, wasnt bad,i didnt start on first oil because garage leaked and i was afraid water got in it.
so i refilled with fresh and it started right up, ran the thing all winter with NO problems at all. Ran like a new one.
Next winter oil was changed before use, and first use, all fine, second use, about 20 minutes into using, engine started to labor, slowed down and stopped dead. you couldnt force turn the engine with pipe wrench on crank pulley.
I let it sit over night, still stuck next day, only tried a little bit with rope pull, shot some oil in plug hole, used pipe wrench, engine came loose, a little at a time, not all at once, i know it was the piston.. Anyway, now 2 years later and it is still going.. So saying a seize for no reason? well sure there is a reason, but who knows why

Any time I get a freebee I do a compression check, this way I know if I can do minimal clean up for reuse, if not I do a complete teardown and check clearances. after that I know if it's junk or reuseable. If it did seize you can sometimes just hone the cylinder and lap the piston, rings, and ring grooves, done this many times and they ran along time for me.

Its got a few ounces of Marvel Mystery oil down the sparkplug hole now, I'll see what it does tomorrow. Although the engine could be turned a bit after the scheeching sound and I stopped it...now its pretty much stuck. Tomorrow, I'll take the shroud off and turn it with wrench. If its still tight, I'll fill the sump/case with MMO.

===> Issues I cleared up (or caused) When I got it (freebie), the flywheel was loose and the keyway on the crank was banged up and the key split in two. I cleaned that up and got the timing right. I actually used it some when we had a small snow a month ago. It worked fine then and must have gotten hot then. This gas in the oil must have had somethng to do with the seize up.

After cleaning the carb, I reassembled the carb with the float upside down which kept the valve open. This could have been the time that a lot of the gas went into the oil. I noticed the problem and re-installed the float properly.

The engine looked pretty new when I got it, fairly clean, not much dust, dirt etc, but who's to say it wasnt run low on oil or some such. It did have some bolts replaced with standard thread in metric.

I tested the compression when I got it, it was about 90psi. I have been told this is about right for one of these engines.

Tim

Yep, that's where all the gas in the oil came from. That gas cleaned up the oil sump real good, the I'm guessing the problem now is the crank journal, connecting rod, piston risk pin, piston and bore are probably scored. IMO you have no choice but to tear it down and inspect, rehone, lap, and polish the damaged parts and mic them to see if you can still use them, most likely you can. Even if it frees up you still have the scored surfaces and it will soon have piston slap if you don't take care of it IMO.

I have had rope pull starters make some terriable schreeching sounds.Just needed a tad of oil.Don't forget to look in this area.

Darn it, this gas in the the oil thing really caught me off guard, I had no idea, thats what they call learning the hard way.

So, the Marvel Mystry Oil in the head and in the sump has freed up the engine. It will turn over but there is some rough -ness, sort of scratching/grinding noise and vibrations that I hear and feel when I hand turn it. Its just a slight resistance but it doesnt feel 100% smooth. Could it just possibly be grit in the gears that would clean up with a couple changes of oil. I know this sounds like I am dreaming but I hate to break her open unless I really need to. Maybe I should start with removing the head and looking in the cylinder for scoring on the walls as evidence of wear.

Tim

Glad to see it loosened up. Now, you are at a crossroads.

1)You can get engine oil back in the sump and try your luck. Be cautious and observant as you run it up. Do it carefully and shut the engine down at the first sign of trouble. Change the oil out of it after running until it was to operating temperature.

2)Take rcmoser's advice and tear it down. I would be more concerned that the rod/ crank journal would cause a sudden end your to your Vangaurding experience. It would be a great way to expand your knowledge on small engines.

Thanks Tom. Just to clarify choices:

are you and rmoser saying that

if I throw caution to the wind and take choice #1 that I may do irrepairable damage to the crankshaft journal and the connecting rod. This would make the engine trash due to the cost of replacing these with new parts. Or I may get lucky and the metal bits may be flushed out with oil changes and all may be well.

On the other hand, if I take the more professional approach and open up the case, find the issues (scoring etc) and resolve these issues, then I will spend more $ and time but the results will probably be more satisfying. Of course this assumes I get it right which considering the 'great' job on simply re-assembling the carb is not such a sure thing ;-(. I won't even ask about the consequenses of 'small' mistakes made on assembling the component of the crank case!

Tim
(trying my best)

If you decide to "tear into it", use your digital camera and take lots of pictures as you go. Take pictures from a couple of different viewpoints and angles. Shoot before and after removing parts. This will allow you to have a sequential record of "how it came apart". Once you have found some damage/defects, you can post photos to the thread for advice on what action you can/should take next. If it carries through to the point of "reassembling", the photos taken on teardown will serve as a satisfactory "guide to assembly". Some may have misinterpreted my statement about "no reason for this engine to seize". I was referring to "an engine in good condition with no prior damage to crank, rod, piston or cylinder" and I still maintain that even with gasoline diluted oil, a "good engine" would not have seized up under the conditions you were running it. If you had been out "working" the engine under a load, it certainly would have seized with that much gas in the lube oil. This engine probably already had seized (from running with "low oil level") prior to you acquiring the machine and was "freed up" without giving it the benefit of a tear down and removing the offensive galling and scoring or replacment of unrepairable parts. For the nay sayers, consider the typical 2 STROKE gasoline engine (yes, I know the Vanguard is 4 STROKE). 2 stroke engines survive being lubed with just a relatively tiny amount of oil mixed into the fuel. The reason they can survive is because the crank and rod use roller bearings and more importantly because the induction system runs the fuel/oil mix through the crankcase. This allows heat to be carried out of the crankcase and into the cylinder to be "drafted out" the exhaust port along with spent exhaust fumes. That "tiny" amount of lube oil suffices until you overwork or "lug" the engine.

How bad do you want to tear it apart?
If you are thinking that you could do more damage by running it- it's possible. Look at it this way. If you knew that the rod was going to grab the crank, and you didn't catch it it time, a rod can vent the case or damage a cam when its time is up. How likely that is depends on the amount of damage was done. An engine hot and working hard without sufficient lube is more likely to toss its cookies. If you choose to run it- go slow and be observant.

If I read what rcmoser was saying properly, if you tore it down, clean any aluminum transfer of the crank, clean up the bore a bit with a hone, clean up or replace certain other parts - it would have a better chance of holding together than if you did nothing. He's right, however your typical shop wouldn't do that repair because if really isn't returning the engine to spec and therefore labor spent may not be good money spent. For a DIY guy with time on his hands, it could be a great learning experience. You could go through this and have an engine that blows oil or eventually fails anyway. But your out hopefully not much money either. DO you have access to a hone, calipers etc would be another good question .

The more professional approach as you mention, is really a matter of weighing your options. If you were in a shop faced with this situation, they would be likely pricing out a short block vs a new engine. Some shops will still rebuild, but way less often.

I've run into this situation many times before. I give my customer an option of trying it, basically doing what you did and hoping for the best. Many times it works out and if not, it is usually BER anyway.

I would have to say people throw away way to much stuff and I don't like being the guy that says better money is spent replacing something rather than repairing. AT least you seem willing to try! Best of luck. Be sure to let us know the route you took and if it worked out the way you desired.

In this past week,I would have had this engine torn down,and properly rebuilt to specs and running.Wish warm weather would soon come along.I am bored to tears and would like to have had that engine just for something to do.Not one bit of dirt/carbon/grease under my fingernails.lol tbk

Hi,

In the interest of self education I decided to do both options #1 and #2, ie put it back together, change the oil, and start it up and run it gently with a careful ear for trouble. So, I started it up and ran it on idle, it smoked like crazy. After about 2 minutes it started to bogg down and then died. When I hand cranked it, there was more resistance than when it was cold, so I think its fair to say that something is seizing up. Now that I have that settled, I'll drain the oil, remove the engine and open it up on the bench.

I recall that it freed up when I put oil in the cylinder so I am suspecting to find some damage in the cylinder walls. Can somebody tell me - will and engine seize and release from piston/cylinder friction or is that more a symptom of seizing in the rod/journal rod/wristpin bearings?

Well, I'll post more when I get it opened up in a day or so. Sorry to drag this out but I promise to keep the forum updated till the conclusion.

Tim

"Seizing up" is usually due to galling of the piston and cylinder bore surfaces that occur from lack of lube and/or severe overheating. Because the skirt and sides of the piston have such a relatively large contact area against the cylinder walls (compared to the area where connecting rod encircles the crank), when components begin to gall the cumulative friction or drag from the piston can become great enough to stop the piston from moving. In contrast, the surface area on the connecting rod to crank is too small to effectively seize the engine (although damage here will certainly "try" to seize the engine). When galling occurs between the connecting rod and the crank, the end result is usually that the rod begins "knocking" and next (it can occur in mere seconds) the connecting rod breaks. This extremely violent failure can blow holes through the crankcase. Seizure of the piston can also result in a connecting rod breaking if the piston "seizes solid" in the cylinder. This is more likely to occur in multi-cylinder engines where a particular cylinder seizes first while the other less affected cylinders continue to produce enough power to keep the engine turning up to the point that the connecting rod cannot carry the load of the galling metal. Wrist pins almost never seize due to galling but instead seize due to the piston becoming distorted and eccentric from the overheating and stretching that happens in piston seizure.

IMO you should of torn it down first, but that's me, the short block may be trash now. Usually when alittle gas or running them low on oil caused a seizure they sometimes can be just freed up when they cool down and the problem resolved, then, sometimes they last quite awhile. but, not without issues, they make little noises you never heard before and will probably use more oil. Course the byproduct of this is less power also.

With the large amount of gas that you said was in the oil sump this deluted the oil beyond it's capablity to clean, cool, and lubricate which resulted in over heating which caused the seizure. Think of it this way you learned two valuable lessons, One about carb. and floats and two about how the lubrcating system works. So it wasn't a total lost, and you have alot of spare parts

Man oh man you guys are gonna kick my bu** when you hear this.

Okay, so I drain the gas out of the BCS walk behind tractor and bring it into the garage to dismount the engine. My buddy and I unbolt the engine and it comes off with the dry clutch attached. We notice that there is a lot of grey aluminum shavings inside the case...hmmm. We look closer and staring back at us, hanging out of the clutch is this 2" long set screw that has come loose, backed its way out and is grinding against the inside of the case. This caused the screeching, the stalling and the grinding feeling when turning it over. How putting MMO in the cylinder freed up this *seize* is a mystery to me but at the time it sure seemed like it did. I was happy to find this cause it meant that the engine is still good.

The next day we got hit with a snow storm so I rushed to put it back together. The set screw got a few drops of LocTite blue just to be sure it dont come out again. Actually I was a little over zealous and broke the allen head on that set screw when I tightened it...hope I dont have to take it out. I also managed to cross thread one of the 4 mounting points on the engine pto side, forgot how delicate the cast aluminum threads are...mixed up some 15 min epoxy and put the bolt back in.

By the time I got her all back together there was 5" of powder snow on the driveway. I put gas in the tank and she fired right up - not having the drag of the set screw cutting a rabbet into the aluminum case sure helps things a lot ;-) . It works fine. Thanks to all of you for all your help and suggestions expecially *mownie* who said back in the beginning
"....Check the components that deliver the engine power to the wheels and make sure something there is not seized or locked up before you devote all your time to the engine per se."

Maybe I got lucky with the set screw backing out and causing all this. It sure prevented the engine from seizing up due to gas diluted oil and now I know how exactly gas in the oil can ruin an engine. In addition, I know how to go about rebuilding it and have looked through the B&S rebuilding steps on their web site. This isnt the same as the experience of actually doing it but its something.

Thanks again,
Tim

I'm glad you got lucky on this one. Your purchase price is getting sweeter. LOL

Bought a used 16HP garden shredder, Called a Merry Tiller, what a name. Kohler Engine exhaust points straight up to catch rain I guess, anyway I kept it covered all winter and when I tried to compose my leave file in the spring, I broke the starter cord on the first pull. Engine has seized-up during the winter. Internet search brought me to Engine Release. $24.95 got my Kohler running fine. Kohlers are the most expensive small engine to repair in the world, I donÂt know why.

Here is a link that might be useful: The liquid solution for your seized engines

"Kohlers are the most expensive small engine to repair in the world, I donÂt know why."

I couldn't tell if you were serious or kidding?

I love Kohlers. I've put tons of hours on them with very few repairs, so to me they don't cost much at all.

Gas in the oil is bad news- as mentioned. One of the very first things i do with a new toy is change the oil- the next is clean the carb- then i try to start it- specially if its sat for any length of time. Metal screeching is not a good noise- ever. Id try removing the spark plug and liberally spray with pb blaster to try and break the rings free- let it soak! Ive had a seized 11hp briggs break loose after the PB blaster trick- i recieved it in that condition. When gas saturated the oil it thins it out, which is bad on splash type oiling setups. A good thing to install is a fuel cutoff valve to prevent this from happening again.

Kohlers are the most expensive small engine to repair in the world, I donÂt know why."

I know why cause they are the most expensive engines sold!

So that equates to the the most expensive parts to buy...
I liked the old cast Iron ones along with Wisconsin's.Not a fan of the newer ones IMO they cheap'en them, but still want preimum price.