I tipped my mini excavator

[Modrob]

Sort of related but the hydrolock thing caught my attention…couple weeks ago when the outer bands of Helene dumped some serious water on us, I had our Power Trac (Kohler 25hp gas) sitting out but had a tarp over the engine and the hood down to keep it secure. When I was finally able to get to it, tried to start and it would just “bump” like low battery. Tried charging the battery (it was fairly new) and no difference. Getting my hands in to try and turn it over by hand it would move so far then “bind” up. With the troubles I have had recently I thought I’d take the head off the previously troubled side and investigate for bent rod etc. Upon starting to lift the head, some water started exiting. Getting it off, I found a good bit of water sitting on top of the piston. Never having experienced hydrolock before I thought I’d now seen it. No bent pushrods. Cleaned out both heads, then hand cranked it a few turns. Pulled carb as well and found water inside it! Back together, removed plugs, cranked and blew some residential water out. Running fine now. Would not have imagined water getting into it but those storm rains were heavy and at times blowing sideways…

 

[bigtiller]

I knew if there was anyone other than me who could utter these words, as if you've had multiple vehicles on their side multiple times, it would be you or Renze.

A buddy in high school accidentally rolled his jeep when he hit a high railroad crossing off-plumb, with a bunch of us in the vehicle. We got out, stood the thing back up, and did it like 3 more times.

We did the same thing as teenagers in a 1950 ford. And then we went to town and got some more kids and did it again. We did it every night for a week. We finally parked the old ford on the main drag through town so all could admire our achievement. Fun times.!!

 

[sd455dan]

When you tip them over, you need to make sure no fluid is in a cylinder. The reason is you can hydro-lock the engine and cause damage like bending a rod. To prevent this, you would first pull the injectors or glow plugs and crank it over to rid any fluid. Good video:

That is one advantage of some diesels being equipped with an exhaust valve opener mechanism that allows the fluids to be expelled without hydro lock. No need to do anything but flip a lever and make sure the fuel stop is also pulled before hitting the starter after an unfortunate event to clear the cylinders out.

Here is hoping that muffler is just full of oil and burning it off.

Does the engine sound normal all cylinders firing?

 

[jrsavoie]

Hydro-lock seems unlikely, if it was only on its side for a few minutes, unless it was some old engine that was already burning oil thru leaky rings or stem seals. But still always best to check all fluids, then remove glow plugs or spark plugs from all cylinders prior to cranking, to ensure all cylinders are dry enough to run.

If the smoke had lasted several seconds after re-starting, I'd have guessed a small amount managed to leak into the cylinders while the machine was on its side. After all, it's not like piston rings and valve stem seals suddenly become porous, just because the machine is on its side.

Someone mentioned coolant in the cylinders. Tell me how that could happen? I'm having trouble understanding how there's any path between cylinders and coolant, no matter which way you flip the thing. The coolant on these machines is a closed and pressurized system like any car, right? If there were some leak path dependent on gravity, your system would never pressurize, and the coolant would boil off.

Oil on exhaust seems possible, esp. if somewhere downstream that's not super hot, as that's the only way it'd keep smoking after several minutes. Still, seems unlikely, unless there was a lot of it.

Damage due to hydro-lock, although unlikely in my opinion, could cause continued smoking and the stalling under load that the OP describes. A bent connecting rod or broken valve stem would be sources of continuous oil intrusion thru piston rings or valve stem seal.

I work on gassers, not much experience with diesels. Can you run compression and leak-down tests, to see if anything serious was damaged? Short of that, if you can't find any obvious external source for the smoke (eg. oil on exhaust), then I'd be pulling the valve covers to check for damaged valve stems, etc. Last resort is pulling a head to check pistons, but at least on a gasser, you can usually debug that by compression and leak-down tests.

Why not on a diesel?

 

[WinterDeere]

Why not on a diesel?

?? I don't follow your question.

The only thing I said about diesels, is that I have less experience working on them, versus gasoline engines.

 

[MinnesotaEric]

NEXT time?

Anytime I look at mini excavators, among other things, I look to see if the boom is twisted from a tumble. I think the Wacker-Giel versions are the only minis with a tilting track system to level out the house to try to keep them from tumbling over.

 

[DutchInNZ]

It did not turn over, but then later on it did when you persisted, and now a hell of a lot of white smoke. So much smoke and that white colour, that is no diesel, that is definitely coolant. Most probably it was indeed hydrolocked and that, because of the too high pressure, the head gasket blew out someplace. That is the cheap consequence; the other might be that you cracked the head, but normally a gasket gives way sooner than that. I would not worry about the pistons and connecting rods either; also those can stand a lot more than a gasket.

 

[gstrom99]

Too bad the OP hasn't come back and posted since last Thursday, with a response or update...

 

[sd455dan]

It did not turn over, but then later on it did when you persisted, and now a hell of a lot of white smoke. So much smoke and that white colour, that is no diesel, that is definitely coolant. Most probably it was indeed hydrolocked and that, because of the too high pressure, the head gasket blew out someplace. That is the cheap consequence; the other might be that you cracked the head, but normally a gasket gives way sooner than that. I would not worry about the pistons and connecting rods either; also those can stand a lot more than a gasket.

One whiff of that exhaust and the OP will know if it is barely burned diesel or antifreeze. Sickly sweet -coolant/water

Unburned diesel will smell like diesel.

If it runs and sounds normal I would pop the radiator cap see if still full, put a nitrile glove on the filler, fire up the engine and see if it pumps up...(head gasket) and if not run it to see if the smoke clears out if it continues to sound normal also would check the oil first and the air filter is not contaminated either.

 

[ruffdog]

I wonder if a cyl liner could crack with a hydro-lock?

 

[DutchInNZ]

I wonder if a cyl liner could crack with a hydro-lock?

Guess not; liners are thick steel, structurally stronger than e.g. the top of an aluminium piston. The weakest point is the soft, pliable material of the head gasket and in many places that covers just a few millimetres of separation between the cylinder and one of the coolant channels. I suppose that the hammering of repeated starting with a small enough hydrolock (engine oil leaking along the piston?) could make just enough of a leak there to get rid of the blocking liquid but then of course the coolant is sucked in later on.

After 45 minutes running, I doubt that the machine would still blow smoke if it were caused by some diesel from some place. How would that much diesel get there from out of the tank, anyway?

sd455dan is right: check the coolant level and bubbling in the radiator; that is the best indication.

 

[Fixastuff]

Its usually a slightly bent rod or two from this type of thing in diesels. They usually still run but with low power and smoke because that cylinder or two don’t combust properly because they’re isn’t enough compression anymore.

 

[DutchInNZ]

Its usually a slightly bent rod or two from this type of thing in diesels. They usually still run but with low power and smoke because that cylinder or two don’t combust properly because they’re isn’t enough compression anymore.

Compression loss is there in any case because he says there is too low power for the hydraulics. I have seen the effect of a bent rod once before, but not that much smoke as in the pic and not that white in colour, much more greyish, but that can be the colour variation of the photo itself. The running of that bent one also sounded a rougher with one cylinder missing and here he says that it runs well. An expensive repair it is in any case. Hope he comes back and tells us.

 

[AnotherBueller]

When the engine is running and sucks fluid that happens but if the engine was stopped and gets filled with oil then it can’t turn at all.

The damage can be done if it only gets enough liquid in to the next cylinder to enter the compression stroke so that the liquid volume exceeds the TDC volume. That's when things get damaged. Hand crank for enough rotations so that each cylinder goes through 3 or more full cycles. (intake/ compression is one stroke / rotation, then power / exhaust is a second rotation)

 

[AnotherBueller]

I wonder if a cyl liner could crack with a hydro-lock?

Hydro lock happens at Top Dead Center so the weakest stuff valves, pistons and con rods take the damage.

 

[DarkBlack]

It's not the starter motor bending a rod. It's another cylinder firing and bending the compressed rod in another cylinder.

I have to agree with 4570Man, and even though you got 8 “likes”, I don’t see your explanation making sense on this post or your previous saying a valve getting bent by the starter motor.

For a cylinder to hydro lock it has to be on the compression stroke. This means neither valve in the cylinder is trying to open, so no valves getting bent.
Secondly, since the hydro locked cylinder is the cylinder on the compression stroke, which means this cylinder would have been the cylinder to first fire. Depending on the number of cylinders ( mini excavator) probably 3 cylinders max? Then the other 2 cylinders wouldn’t be on the compression stroke, to fire a power stroke.
Lastly, with a hydrolock for the little starter motor to overcome, a single adjacent cylinder burning some diesel at almost 0 rpm’s is going to produce little rotational torque. Crank your tractor for a 1/8 of a second. It doesn’t start, It takes many rotations.

 

[Topzide]

A hot motor can fire off pretty quickly! What if the cylinder was the last to go to compression? There's more info needed to armchair this one. Seeing that the OP has "ghosted" us, we may never know. I just know that when you tip an engine, whether on its side or completely over, give it time to drain fluids back down. Then, before starting, remove spark or glow plugs, pending fuel type. JM2C

 

[DarkBlack]

What if the cylinder was the last to go to compression?

I ruled that out because he stated he tried a few attempts to get it to turn over. That should place a resting engine with the hydro lock cylinder on compression stroke as “First up” on the next restart attempt

 

[DutchInNZ]

Hydro lock happens at Top Dead Center so the weakest stuff valves, pistons and con rods take the damage.

On the net there are a few videos of cars driving at speed through flooded streets and getting a lot of water into the engine intake. They just make it but then you can see them starting blowing thick white smoke out of the exhaust. Those are petrol engines so there is no unburned diesel, so it can only come from a blown gasket. Whether diesel or petrol, the lock effects are the same and valves and pistons are definitely not the weakest in this game. Hydrolock happens when the piston is before top dead centre; if it reaches top dead centre you're safe.

@Fixastuff
You of course may be right, because Indeed, a rod may bend, but that depends on the angle it has on the upstroke. If the lock happens when the piston is halfway, the angle of the rod is greatest so the bending force is at maximum. When the piston is just before the highest point, the force vector is again only lengthwise and in that direction rods don't bend really well. I would not know the effect on the bearings.

 

[deezler]

Here is hoping that muffler is just full of oil and burning it off.

Does the engine sound normal all cylinders firing?

OP said it stalled whenever he tried to flow any hydraulic oil (load the engine). Not a good sign.