What's this hole or connection on the left side between muffler & engine? (L3650)

[J-H]

It's really too loud to tell where it's coming from.

Messick's seems to think I don't have injectors, or that they're named something else. All I can pull by name is an injection pump or components.

Am I going to be able to get at this without doing a bunch of disassembly?

 

[Pau7220]

IMHO, the loudness sounded a little scary... that's why I made the catastrophic failure comment. Checking compression... most use the glow plugs with a Harbor Freight diesel tester. Injectors go in the head also.... follow the lines from the pump. Neither require major disassembly.
FWIW, it may be wise to carefully pull a drain plug and take a small oil sample.... Or if you have an extractor or suction-discharge gun you may be able to get a sample through that side fill oil cap or the dipstick. If it looks like metallic paint that would tell you not to run it any further.
You can also drop the alternator belt off just to eliminate the water pump and fan shaft bearings as a possibility.
More questions... did your coolant level change? Any chance it overheated? It's hard to tell in the video if the fog is coolant or unburned fuel.

 

[Fordtech86]

Messick's seems to think I don't have injectors, or that they're named something else. All I can pull by name is an injection pump or components.

They call them nozzles.

 

[J-H]

My neighbor, who is a retired diesel/heavy engine mechanic (used to work for Cat) and who has his own little stable of heavy equipment (grader, dump truck, forklift, backhoe, and more) came over this evening.

1) The dipstick showed nearly no oil. We put 5 quarts in to get it to a healthy range. Apparently when that oil cap blew off, I lost a lot more oil than I realized. Uh-oh. Still not sure why the oil cap blew off in the first place. There may have been an underlying or pre-existing issue that caused that.

2) He had me run it, and did some listening and feeling along the engine block. His diagnosis is that it most likely has a messed up rod or rod bearing inside the engine, causing one piston to not compress fully, thus generating the white exhaust and ugly noise.

Apparently "take apart the engine for repair" is such a big chore that it may be easier/cheaper/safer to drop a replacement engine in there. He is not sure he wants to do the job.
I personally am not equipped to do it (knowledge/time/engine lift). He says he'll help, but I'm not sure how long it'd take. This may be something I'm better off outsourcing to the local dealer.

 

[kubotafreak]

The generic test for excessive blowby is how much the oil cap dances on the valve cover when you unscrew it. They go from no movement/smoke to puffing like a coal train. Cracked/worn ring lands, or valve issues is the common cause, if the engine is not just worn out. Has the valve cover been off that engine? Hose either blew off or was removed.

 

[J-H]

My neighbor, who is a retired diesel/heavy engine mechanic (used to work for Cat) and who has his own little stable of heavy equipment (grader, dump truck, forklift, backhoe, and more) came over this evening.

1) The dipstick showed nearly no oil. We put 5 quarts in to get it to a healthy range. Apparently when that oil cap blew off, I lost a lot more oil than I realized. Uh-oh. Still not sure why the oil cap blew off in the first place. There may have been an underlying or pre-existing issue that caused that.

2) He had me run it, and did some listening and feeling along the engine block. His diagnosis is that it most likely has a messed up rod or rod bearing inside the engine, causing one piston to not compress fully, thus generating the white exhaust and ugly noise.

Apparently "take apart the engine for repair" is such a big chore that it may be easier/cheaper/safer to drop a replacement engine in there. He is not sure he wants to do the job.
I personally am not equipped to do it (knowledge/time/engine lift). He says he'll help, but I'm not sure how long it'd take. This may be something I'm better off outsourcing to the local dealer.

One rod bearing had chewed itself up. The $35 part has been replaced, oil/filter changed, etc., and the tractor is running now. He did not have to take apart the engine, just move axle/driveshaft/etc. and take off the oil pan to access the crankshaft and rod bottoms. About 10 hours of work by someone who knows what he's doing and has the tools to do it right.

I have been advised to change the oil again in 2-4 weeks, as any metal bits that were up in the engine will need to work themselves loose.

He also identified that there are warning lights on my dash for oil pressure, air filter, and alternator function that should light up. None of them light up ever, so I've never even known they existed. I'll probably make a separate thread for that here in a few days if I can't find an obvious broken connection.