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Discussion Starter #1
This one has me scratching my head a bit... My dad's tractor developed a bit of a knocking sound last spring, so I pulled the pan thinking it was bottom end bearings, as with the stethoscope, the bottom is noisy. I plastigauged all the mains and rods, and they all checked out ok. The oil pressure is around 60 lbs at idle, and I went ahead and adjusted the valves since they hadn't been done for since he put the motor in back in the 80's... This motor has never been torn down likely since it was built, and when I listen with the stethoscope, the head area and middle of the block are pretty quiet, but the bottom end has just gotten louder.I'm thinking perhaps we should just throw in some bearings for good measure, but std bearings are definitely not cheap, but of course, neither is a crankshaft if one goes. It does appear to have the original injectors as well, but it has no smoke or missing at all, runs as smooth as always. Listening to the injector pump is noisy, but it may just be how the Roosa's are, can't answer, should probably compare it to my 6.9. Opinions/ideas?
 

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how did the bearings look when you used the plastigauge? were they down to the copper or anything?
 

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Discussion Starter #3
For as many hours were on the motor, I have never seen such clean bearings. No copper at all, the lead was still there, just a little scratching as would be expected. Had they shown me copper, I would have switched them out.
 

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I have never had much luck myself trying to listen for where a knock is coming from, the sound always seems to resonate to a different part of the engine. Have you cracked each injector individually to rule out injector knock from a bad injector?
 

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Discussion Starter #5
I did do a few, but wouldn't a bad injector also be accompanied by smoke/missing?
 

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I agree, and actually considered that before posting my original post, it's just that I don't know how many times I have overlooked the simple solutions because I didn't think the symptoms warranted the simple diagnostic.

Other ideas, (not really being familar with IH engines) excessive crankshaft endplay, failed harmonic balancer, or bad camhaft and lifter.

Good luck I hope whatever you find isn't to big a problem.
 

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Discussion Starter #7
For the most part, the IH engines are set up like most, not anything exotic or unusual. I hadn't thought about the balancer, and that does make a bit of sense, and I'm sure it is factory original. They use solid lifters on the cam, and all the rockers were pretty close on adjustment when I reset them. The injectors are controlled by a Roosamaster rotary pump.
 

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Hacky!
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Dang, I was just going to suggest the vibration dampner. I truly believe that is the problem. That will most often times be the reason. Have you noticed any oil leakage in the front of the engine, especially from the bottom end.
 

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Dude, I just remembered this. My grandpa used to feed cattle with this Farmall 560 that had an IH D282. It started knocking real bad so I dropped the pan ( not really knowing what to even look for ) and noticed the crankshaft was broken in two at one of the main bearings. I think it was right at the #1 main. Might look at that.
 

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Hacky!
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Dude, I just remembered this. My grandpa used to feed cattle with this Farmall 560 that had an IH D282. It started knocking real bad so I dropped the pan ( not really knowing what to even look for ) and noticed the crankshaft was broken in two at one of the main bearings. I think it was right at the #1 main. Might look at that.
That is exactly what happened to mine.
 

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Discussion Starter #11
I don't think this is really a mechanical knock. It is more prominent with higher rpms, and just sounds more like a preignition knock. It is nearly quiet at idle, just a hint of a ping or knock. Mechanical knocks most times give a feel of a knocking somewhere, but I can't find one this time. Also, when you revv the motor, it sends out a lot of black smoke until the engine catches up. Never used to do that... I'm wondering if it isn't the governor in the injection pump. It was a used pump we put on when the other seized, and still has red paint on it... I did check the balancer, and it looks to be ok, the rubber insulator belt looks intact, not wobbling too much..
 

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Hacky!
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:thinking

Boy I know these 407's. You have got me stumped..
 

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Can you play with the injecton timing to see if the problem comes and goes at different timings?

Just feeling my way here, but if your governor is failing, then my thought is that if you play with the pump timing and it runs better at the higher rpms, but now the idle rpms are rough or it is hard starting, then it would tell me that the governor is no longer advancing the timing as it is supposed to, or it may be over advancing it.

Just my pennies worth.
 

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gone fishin!
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your rack limiter has been adjusted or has slipped. the base timing cant slip cuz the rossa's are keyed, also there is no rpm advance on the rossa pumps, only the stanidine pumps advanced the timeing. on the back of the pump is the rack limiter, turn it out to decrease the fuel, in to increase. the knock you are hearing is the motor trying to deal with way more fuel than its designed for, its a idi head so they dont cope with the extra fuel dose that its getting
 

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Discussion Starter #15
No one has adjusted anything, so if it is out of whack, it would have slipped. It changed pretty much suddenly. Basically, last spring, my sister was running it down the road when the noise first occurred, so that's why I checked out the bottom end. Well, practically the same thing again recently, just all of a sudden the noise got worse when she was running it down the road.
 

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gone fishin!
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does it only knock under a load? when your accelerating? if you rev the motor up and chop the power quickly, does it knock as it slows down?
 

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Bad trust washer on crank?
 

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Discussion Starter #19
It knocks a bit on accel, not on decel. Almost sounds like ether knock... It does have the ether can on it, which does get used.I did take the can loose to be sure it wasn't kicking any in as well. It knocks all the time, not loaded at all.
 

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thrust washer wont make her knock will it?????? usualy you get a lug squeel, not a knock............
I've seen them broke and in the pan before. Anything is possible.

Ether type of knock? Hmmmm. I've heard a spun rod bearing on a Deere 4010 diesel sound like that before. But, if it is doing it on all 6 holes, it sounds like a fuel injection pump timing issue to me.
 
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