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Hi there we got a 485 quadtrac with engine vibration i have disconnected the drive shaft from engine to trans and removed but vibration still present seems like its the worst from 1000 to 1200 rpm and starts again from 1500 to 1750 but is less noticable. engine was rebuilt 2 years ago and problem was there before rebuild and is still here. Wondering if any of you have run across this issue any help or feedback would be appreciated.
 

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I believe there could be a damper on the flywheel that can do that. I’m not sure about your model but the 600 that I drive in the spring needed that replaced once because of a similar symptom. I wouldn’t be surprised if it needs done again someday either.
 

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Hi there we got a 485 quadtrac with engine vibration i have disconnected the drive shaft from engine to trans and removed but vibration still present seems like its the worst from 1000 to 1200 rpm and starts again from 1500 to 1750 but is less noticable. engine was rebuilt 2 years ago and problem was there before rebuild and is still here. Wondering if any of you have run across this issue any help or feedback would be appreciated.
Hi there we got a 485 quadtrac with engine vibration i have disconnected the drive shaft from engine to trans and removed but vibration still present seems like its the worst from 1000 to 1200 rpm and starts again from 1500 to 1750 but is less noticable. engine was rebuilt 2 years ago and problem was there before rebuild and is still here. Wondering if any of you have run across this issue any help or feedback would be appreciated.
could be poor injectors
 

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I've had the damper flexplate off on the rear flywheel and its still doing the same thing we also took off the viscous damper in the front and also same result.
 

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Ok...but if yd we have the driveshaft going to transmission disconnected the hydraulic pump should not be working? unless you're talking about pump that drives the cooling fan motor?
 

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took off the viscous flywheel from another tractor that not having an issue and will put it on the 485 and see what happens
 

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I do think that the dampers can degrade and by replacing them at that time it can be a noticeable improvement. Unfortunately the vibration phasing you are experiencing is likely inherent in the design of a six cylinder inline engine where individual counterbalancing for each cylinder is likely done on the crankshaft itself in the absence of a separate counterbalancing shaft in the engine block. ( some 6 cylinder inlines have no crankshaft counter weights )

I presume this engine series has no separate counterbalance shaft, and it would probably operate smoothly again at it’s maxim rated high idle speed over 2000 rpm? It might shake again at 2500, but it isn’t permitted to go up there. Counter balance shafts allow some engine configurations to exist that are otherwise difficult to impossible to balance to an acceptable state.
 

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If I remember correctly this is an Iveco engine, first thing is the damper on the back of the engine but it sounds like you eliminated this. Next I would do a cylinder cut out and see if there is one cylinder that does not make the vibration worse indicating that it may be something with just that cylinder ie bad injector or low compression I would do this test because it is easy to do however I have yet to find any issues this way. I suspect that the camshaft timing is slightly off, there have been a few that have come from the factory this way with these symptoms and retiming the cam has fixed the issue. These engines can run very smooth if timed properly but will get odd vibrations if they are off, they are pretty sensitive to the cam timing being slightly off. I can't remember off hand if this engine has the "super charger" after the turbo, basically a compressor half of the turbo driven off of the flywheel. If it does you might make sure everything is good on that, gears and bearings, before going and retiming the cam. Are there any other symptoms, hard start, excessive fuel consumption, oil consumption, anything like that? How many hours on the engine total and after overhaul? Who overhauled it? How much of an overhaul did it get?
 

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Rebuilt a few of these myself. The timing is sensitive and odd if you're used to North American built engines. Dial indicator on the #1 injector, crank it through a cycle, watch the needle. Has to be in a certain range. PIA to do if you ask me, but that's what it requires. If it were mine I'd get rid of the compound turbine unless you're not using it to pull very hard. Backs up the flow of exhaust too much and will take out your valve guides, then the valves score the cylinder liners and pretty soon you've got a mess. You will loose some hp, but the engine will last way longer. All the 485's around here have that and the PTO unit removed.

That being said, if anyone is looking for the turbine unit and the PTO unit is uses to put power back on to the flywheel, I've got two essentially new ones I'll make a heck of a deal on. I've got a regular turbo (Holset, needs rebuilding but cheaper than a new one) and a water pump (works fine) too.
 
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. If it were mine I'd get rid of the compound turbine unless you're not using it to pull very hard. Backs up the flow of exhaust too much and will take out your valve guides, then the valves score the cylinder liners and pretty soon you've got a mess. You will loose some hp, but the engine will last way longer. All the 485's around here have that and the PTO unit removed.



Does this apply to all of these tractors, ours is a 2018 540. TIA
 

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WOG your correct I felt like I was explaining something wrong on the “compressor” to the flywheel. What have you guys done? Do you just pull the unit off and use the original turbo? Is there any programming needed?
 

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Those models were turbo'd differently. The 485 utilized the secondary turbine to put mechanical action directly to the flywheel. These tractors had essentially the same engine as the 435 and this solution (mostly found in European trucks with these engines) was their way to add 50 HP. I didn't work well at all. Exhaust temps were way too high and the valve guides would fail. Thus it was my understanding that they only did this on 485 models (2007-2011). The tractors that utilize two true turbos are less prone to this exact problem.

If you're concerned however, if this happens, your tractor will run fine. No knocks or noticeable loss of power. However it will start pumping oil out the breather tube at about a 1.5 gal/hr or more. At high throttle, the blow by will also be.....more in line with a rock concert fog machine. If you measure the crankcase pressure it will be far in excess of 36" of water (measured with a manometer), normal should be around 12-16". Obviously if allowed to continue the valves will not only score the cylinder sleeves but will drop into the cylinder while running. Then things get uncomfortable on a whole different scale.

Hope this helps
 
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