Loud Engine Knocking

[olink]

Looking for help in diagnoses before I tear into this thing. Have a FarmPro 2425 with Y385 engine. Most recently been grading and land clearing. Have a couple of small hydraulic leaks, so before the long day began, I topped off the rear Hyd for the drag box operation. Just a few minutes into working, I backed into a stump and bent dragbox braces and stopped the engine while I attemped to straighten braces. Needed tools, so I headed back to the garage with the tractor. About 100 yds later, the engine started a load knocking. I shut it down immediately. checked oil and found it to be about 2qts high...over filled. Drained the oil and put in new oil to proper levels. Started just fine, but the loud knocking continues. Never got any indication of overheating, had good oil pressure. Engine only has about 40 hours on it. I used to rebuild VW engines as a young man, kind of sounds like I dropped a valve? I have absolutely NO experience with diesels. Anyone want to give me a starting point? Pull the valve cover? Or could this be some sort of a fuel issue causing the knocking?...like a misfire? Oh, tractor is out of warranty, bought in April of 2003. Suggestions/comments very welcome and much appreciated. OLY

 

[RodgerF]

I bought a TC30 but I did a lot of reading on the chinese tractors too. First, you should post this in the Chinese Tractors Forum. There are a lot of knowledgeable people there. Some are even dealers but we won't hold that against them. /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif

After you changed the oil and it started knocking again did you check the oil a second time? I've read where a seal in the injector pump went bad and dumped fuel in the crankcase.

Search for injector pump here or on one of the Chinese specific boards. I know I read about this problem somewhere, just too old to remember where. /forums/images/graemlins/crazy.gif

Good luck,

Rodger

 

[olink]

Thanks for the response. I'll post on the chinese board too. No, I didn't run the engine long enough after the oil change to see any difference in the oil level again. .... to affraid of doing further damage to the engine by running it. Am headed out right now to pull the valve cover and see if I dropped a valve.
Thanks again.

 

[slowrev]

Is the hydraulic pump engine mounted, if the shaft seal leaks will it go into the oil sump ?

 

[olink]

Thanks ...I'll add that to the list of things to check. I've been to busy with thte military to get to it this week. I'm pretty sure the pump is engine mounted and what you say make since ...It has to be either or both a leaking fuel injector or a seal letting hydr fluid into the crnakcase. If my nose was any good, I'd be able tosmell the difference in the crankcase oil ... Ha! I'm on my way out now to try and find the problem... thanks again!

 

[JimR]

If you dropped a valve the motor would be skipping. You may have spun a rod or something a lot worse.

 

[chim]

Did you use a diesel-rated motor oil when you changed it? Motor oils are rated for different applications, and it's important....................chim

 

[RoyJackson]

I'd suggest you have a rod bearing going bad...maybe.

I'm sure you haven't dropped a valve...your tractor wouldn't be running if you did.

However, it's almost impossible to diagnose an engine problem on a forum such as TBN. If you don't know what the knocking is, you need to get an experienced diesel mechanic to listen to the engine.

 

[rdbrumfield]

I too thought I had dropped a valve when the engine started to knock. Listened to it with a scope I couldn't figure it out, only 240 hrs on it. As it turned out, it was a faulty connecting rod bolt that had snapped and was letting the piston slap the head and of course letting the rod knock. Do you think that they would stand behind it? Of course not.

 

[olink]

Thanks for all the help guys. I've been posting under the Chinese tractor forum too and have had a lot of good ideas there. I seem to have solved the knocking buy fixing a leaky injector. But, my 3 pt hitch won't work, so I think I have a blown hyd pump seal too...which could be the high oil problem. I changed oil again tonight and ran the engine for about 5 minutes...it isn't running well, but no knocking.. I think I messed up the valve lash..or could still have an injector problem.. anyhow, hyd fluid was spewing from the overflow tube on the rear lift... FEL works fine although I didn't try a load on it, but the 3 pt. will only come up a littebit under high rpm and doesn't want to lower at all. ???

If anyone here has the big picture on setting the valve lash, would youpleasse share it? I found the marks on the crankshaft pulley, severall indexing marks, but knowing which one is TDC is a guessing game. Can't find a picture on the net anywhere. And, I thought you would turn the crank 180 degrees to move to the next cyl. valves, but that didn't seem to work out...

So, I have her running, but has low power and seems to be hitting on 2 cyl just fine and one really weak. She kind of lopes when it is running...

Well, Thanks again for all the ideas. If I don't get her fixed this weekend, she'll be sitting until I finish this next military deployment.. only about 2 weeks...

Later guys...Oly in Fl.