YM336D - Started knocking loud while tilling

   / YM336D - Started knocking loud while tilling #11  
If it was ran low on oil the knock will be bad bearings and that almost 100% always ruins the crank so pulling the whole engine is necessary there to get the crank and cam out and pray it didn't spin a main.

You can pull the oil filter and tear it down (grind the rolled edge off at the top and pull the guts out and spread them out) or pull the pan and see bearing material or even see it in the drain oil you have major issues guaranteed.

Don't you just hate that rapping sound of a rod or bearing in trouble??
 
   / YM336D - Started knocking loud while tilling
  • Thread Starter
#12  
Okay, I pulled the pan, the bearing caps and checked out the bearings and.. good news and WTF news..

The bearings look perfect! (YAY!)

So.. WTF is causing the knocking if not the bearings?

I did notice the oil pickup screen is horribly clogged, but looking at where the dipstick ends, there was still enough oil to fully engulf the pickup screen, so I don't think lack of oil is the cause, though I'm still not ruling it out entirely.

There was plenty of sludge in the oil pan, but no metal shavings beyond a couple of tiny pieces of what looks like copper filings about 1/128" (human hair width) wide and 1/4" long. Maybe from when the bearings were first installed? I did find two pine needles in there, too.. I don't even want to know..

So far so good on the bottom end, but that doesn't help me with the knocking issue. I'll head back outside and lift the valve cover to check for a dropped valve push rod and report back. Hopefully someone will have a new theory by then. So far I'm thrilled the bearings are okay. The main bearings don't look carved up either. I'll take a picture of the pickup screen. What a mess of goo. I'll also cut open the oil filter, just in case. Looking at the sludge in the bottom, it could likely use replacing already, anyhow.
 
   / YM336D - Started knocking loud while tilling #13  
Awesome Domush you are one lucky guy well as easy as the pan is to put back on clean it and fill it up and restart it and see what it sounds like now is my thinking then you can crack injectors to see if shes missing.
 
   / YM336D - Started knocking loud while tilling #14  
Don't you just hate that rapping sound of a rod or bearing in trouble??

Yes agreed jony and as much work as he has done already to it then to have this happen must be heart breaking is all I can say so I know we all are hoping it isn't the bottom end. :thumbsup:
 
   / YM336D - Started knocking loud while tilling
  • Thread Starter
#15  
Here is the oil pickup screen :facepalm:

2012-02-27%252016.53.34.jpg


restart it and see what it sounds like now is my thinking

Do I have to? :eek: I'm so afraid something is going to explode on me when I try it. Keep in mind, when it happened, I did top it off with oil and restart it for a few seconds, and the knocking didn't go away any. I didn't run it for more than a few seconds asI had no idea what had happened. I'm at a loss as to what would knock if not the rod bearings.

I pulled the valve cover and all of the valves look normal, the push rods look fine and the valve springs.. spring as normal. I'm super afraid I'm going to blow this thing if I start it again. Maybe I'll just crank it by hand a few times and see if I can't find a knock or catch somewhere in the stroke. [shivers]

I'll get some fresh oil and filter tomorrow and put it all back together. I'm thrilled about the rod bearings, but this still sucks. :(

Thanks for the guidance everyone, especially you, car doc. :thumbsup:
 
   / YM336D - Started knocking loud while tilling #16  
Maybe its missing, I have heard a big CAT engine on one of my loggers loaders blow out an injector and it sounded just like a hammering rod bearing. Maybe its just missing or deisel hammering???
 
   / YM336D - Started knocking loud while tilling #17  
Maybe its missing, I have heard a big CAT engine on one of my loggers loaders blow out an injector and it sounded just like a hammering rod bearing. Maybe its just missing or deisel hammering???

either that or the oil pump was struggling to suck oil through that crap? you have an oil pressure gauge on it yeh? what was it reading? reassemble it and fire it up and see what happens.
 
   / YM336D - Started knocking loud while tilling #18  
Domush, to stop the sludge in your oil pan and filter screen in the future put some Seafoam in your engine oil and run it to operating temp before an oil change, it will break all that crap up and if drained hot will stop the buildup. It will clean the entire engine up of hard deposits and sludge, since using it in my tractors my oil never turns black anymore, stays golden.

For anyone not familiar with Seafoam, I do not recommend running it in your engine oil at all times, just prior to oil change as it will thin your oil.
 
   / YM336D - Started knocking loud while tilling #19  
Domush,

Yes I think starting it is what is necessary and I would sure put an oil gage on it now also even if you just hang it off the side for this purpose and mount it in your nice dash later.

As long as the bearings all look good all there is left is cam and cam gears and hydraulic pump and lifters and rockers that are oiled so once it all gets enough oil that in itself takes up the clearances and quiets the engine.

So I am thinking even though you had enough oil after topping it off the screen kept the oil from getting where its needed.

You were lucky not enough heat was generated in the crank to destroy the bearings and cause the cascade of destruction that follows this time.

I second the SeaFoam Smoody mentions its good stuff follow the directions and you can add some to the fuel too.
 
   / YM336D - Started knocking loud while tilling
  • Thread Starter
#20  
I already have an oil gauge in the dash. It read 50PSI when I started it up on the day this all happened, but when the knocking began it read 10PSI. I'm not sure when it dropped, as I removed the idiot lights. The new gauge doesn't have an idiot light and I hadn't looked at it since starting it up.

I'm off to town to get the oil and filter now. I already have some seafoam, but seeing as I have the pan off, I'll hold onto it until next oil change. Wish me luck!
 
 
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