Well, I finally did it #*$#&)!!, please help

[wb4rt]

I'm 63 years old and finally did the ultimate small engine mistake :doah:hmy::doah: - after changing my riding lawnmower oil a few weeks ago, apparently I did not completely tighten the oil plug. So while idleing today, I heard a sharp BANG and the engine quit. Yep, the oil had leaked out.

I put oil in and tried to start, but there doesn't seem to be any compression. So I need some guidance as to what to do now. This is a 22 hp Briggs V-twin 407777-0283-G1, 2 cylinder vertical.

I pulled the engine this afternoon and I cannot find any physical damage on the crankcase or heads. No oil is leaking and when I turn the flywheel the shaft turns but neither of the pistons and valves seem to be moving.

I am reasonably handy, but not much of a mechanic.

So what is the most likely damage?

Is it worth paying someone to open the crankcase and fix it?

Should I just replace the whole engine, or could I get a short block and rebuild?

Any ideas what short block or other Briggs engine model will crossover and work?

Thanks in advance for any suggestions, ideas, or recommendations. Heck, at this point I'll just take some sympathy.

 

[Dr. Shop Teacher]

You busted rods. Good news is they didn't fly through the block. Since you have the engine off, drain the remaining oil. Remove the blower housing and any other stuff that may impede your access to the sump cover. Turn the engine upside down, locate the bolts that secure the sump cover to the block, remove and bag them. Gently tap the sump cover off the crankshaft (clean it with sandpaper and steel wool first). Take a picture with your phone with what you find. Note how all the rotating parts are connected together and take several photos.

With any luck, the rods snapped above the crank journals and the crank shaft could be ok but likely burned a bit (it should smell nasty in the crankcase). If this is the case, you may be able to save the engine by replacing the rods and piston rings. You may have pistons frozen in the cylinder bores, and if that's the case, a short block is in order, as the bores are likely scored deeply.

Anyway, worth an hour's worth of time to get a look see. Just take time to document what you disassemble and how you did it. Post some photos so the experts can weigh in...I'm a shade-tree kinda guy.

 

[wb4rt]

Thank you for the reply, Dr.

I have opened a few smaller engines, years ago and always had problems trying to separate the two halves.

Any good techniques to doing that without causing more damage? I suppose I will need a new gasket for that too, right?

Also, if I am able to move the pistons once I have it opened, then you think it will be just replace the piston rods and rings?

 

[The_Ruppster_86]

I pulled the engine this afternoon and I cannot find any physical damage on the crankcase or heads. No oil is leaking and when I turn the flywheel the shaft turns but neither of the pistons and valves seem to be moving.

The crankshaft rotates but there is no valve movement? Rotate the crankshaft a few times and double check. There is a gear on the crankshaft that turns the camshaft (another gear) which operates the valve train

 

[minikenny]

I was gonna say the same thing. Even if both connecting rods snapped simultaneously, the cam should still be working the valves.

Are you saying you spin the flywheel side, the PTO side still spins? That would rule out the crankshaft.

Doesn't much matter I guess, steps are the same like the Dr. says, gotta open it up and look. :thumbsup:

Oh, and Sorry for your loss. :crying:

 

[minikenny]

If too much is toasted inside, here is a place in Atlanta selling a brand new drop in replacement for $530 shipped. I'm sure it would be cheaper if you drove down and picked it up:
Briggs Stratton 18HP OHV V Twin Riding Mower Engine with Briggs Warranty New | eBay

 

[jeep2003]

Now that you told us about it you have to open it up and find out because were all curious. That certainly does suck its not a cheap engine. but luckily you can swap in any vertical shaft engine its not like a car where theyre all different. Hopefully its an easy fix. probrobly just snapped rods. i wouldnt even bother changing the rings

 

[Dr. Shop Teacher]

Thank you for the reply, Dr.

I have opened a few smaller engines, years ago and always had problems trying to separate the two halves.

Any good techniques to doing that without causing more damage? I suppose I will need a new gasket for that too, right?

Also, if I am able to move the pistons once I have it opened, then you think it will be just replace the piston rods and rings?

Generally, there are a couple of tabs around the sump that you can tap with a mallet/hammer. Sometimes you might need a screw driver to tap as an intermediary to get at the tabs. The key is equal pressure around the case. Yes, a gasket will be necessary. As posted by minikenny, getting a look inside is first priority. Without photos, I can only speculate about the pistons. I've blown up my fair share of garden/lawn tractors over the years, and generally it's a rod. What happens after the rod lets go dictates whether the engine block can be saved. I just rebuilt a Briggs OHV that had a busted rod. Piston and bore were fine but the rod cap and bolt tore the "H" out of the crank shaft journal--so I needed rod, rings, crankshaft and gaskets. If your engine is counter-balanced, it's going to look very interesting inside. The counter balance assembly sort of looks like a girdle. Get some photos, sit back a bit and enjoy watching the Georgia Azaleas bloom and we'll all offer opinions.

 

[125ccCrazy]

if neither piston or valves are moving and your trying to turn it over with the flywheel via pull start or elect start my guess would be a sheared flywheel key and the flywheel is spinning on the crank..it's also possible the crank could have broke between the counter balance and flywheel.. I doubt you snapped both rods and cam just idling... Pull the flywheel first before opening the engine up..

 

[wb4rt]

if neither piston or valves are moving and your trying to turn it over with the flywheel via pull start or elect start my guess would be a sheared flywheel key and the flywheel is spinning on the crank..it's also possible the crank could have broke between the counter balance and flywheel.. I doubt you snapped both rods and cam just idling... Pull the flywheel first before opening the engine up..

Hey, 125ccCrazy - that is is great suggestion! I did not think about that but remember the shaft turns when I turn the flywheel.

Since there is nothing to lose I will try your suggestion before more severe surgery.

So, if I pull the flywheel then I might see a sheared key. If that is the case, then it could be as simple as replacing the key?

There is a large nut on the top of the flywheel and 2 bolts on either side of the large one. I guess I will remove the large nut and pull the flywheel up or is there something else I will need to do?

Again, that would be TERRIFIC if that is the fix, but knowing my luck, I doubt it.

Will try pulling the flywheel in the morning and let you know. Otherwise, I will remove the sump and post pictures.

Keep the ideas and suggestions coming!!

 

[Dr. Shop Teacher]

WB--See if you can find an online service manual for this engine. The large nut secures the flywheel to the crank. The two smaller ones may (I don't know for sure) secure the fan to the flywheel. You're going to need some sort of tool to hold the flywheel in place to loosen the nut. You might try a ratchet strap around the flywheel tied up to a post. The engine is going to have to be held in place also. Great idea on checking the key, BTW.

 

[minikenny]

WB--See if you can find an online service manual for this engine. The large nut secures the flywheel to the crank. The two smaller ones may (I don't know for sure) secure the fan to the flywheel. You're going to need some sort of tool to hold the flywheel in place to loosen the nut. You might try a ratchet strap around the flywheel tied up to a post. The engine is going to have to be held in place also. Great idea on checking the key, BTW.

Doesn't seem possible if the shaft is turning like he said. :shrug: Doesn't hurt to take it off either.

 

[minikenny]

Here is the exploding diagram if you need it: https://www.partstree.com/parts/briggs-and-stratton/engines-vertical-engine-with-electric-starter/407777-0283-g1-briggs-stratton-engine-electric-starter/flywheel-controls/

Briggs makes a little puller would make removal easier: https://www.partstree.com/parts/briggs-and-stratton/parts/19203/

If your key really is sheared you might not need the puller.

 

[wb4rt]

Update - the flywheel key is sheared!!

I'm going to pull the flywheel and see what is next.

I'll let you know.

 

[Dr. Shop Teacher]

Update - the flywheel key is sheared!!

I'm going to pull the flywheel and see what is next.

I'll let you know.

May the Briggs Gods be smiling upon you!:smile:

 

[wb4rt]

Well, not good news. Finally opened the case and both rods were disintegrated, at least one piston broken, about 1" of one cylinder wall broken out, cam shaft broken, crank has some marks, and the oil pan is cracked.

I can post a couple of pictures if anyone is interested.

Sooooo . . . new engine will be here Wednesday.

My sincere thanks to each one of you for your help and suggestions. And your sympathy.

One of my old platoon sergeants had a great quote that applies here "Trooper! if you're looking for sympathy it's in the dictionary between Sh*t and syphillis".

 

[Dr. Shop Teacher]

So sorry...good luck installing the new engine. Done burn up good...

 

[jeep2003]

ouch well maybe you can sell some of the good parts to recoup youre losses. shit happens

 

[minikenny]

Well, not good news. Finally opened the case and both rods were disintegrated, at least one piston broken, about 1" of one cylinder wall broken out, cam shaft broken, crank has some marks, and the oil pan is cracked.

Ouch. All from one bang?

I can post a couple of pictures if anyone is interested.

Sooooo . . . new engine will be here Wednesday.

My sincere thanks to each one of you for your help and suggestions. And your sympathy.

One of my old platoon sergeants had a great quote that applies here "Trooper! if you're looking for sympathy it's in the dictionary between Sh*t and syphillis".

New one is the cost-effective solution when there is that much carnage. :thumbsup: Should be a drop-in pretty much plug'n'play.

Don't forget to add oil! :facepalm:

 

[125ccCrazy]

all that happened just idling? what was it idling at, 7300?.... :scared: I would have never thought that much damage could happen at that low of rpms.. I've seen a lot less damage at extremely high rpms..