B3200 Vibration Update

[leonz]

screener story



we had a installed a new screening plant to replace the old one(stupid move)

So anyway the scfreener was an 8 by 14 screener with tow screen decks to screen salt -wait it gets better believe me.


So we fired op the screening plant to commision it and we were delivering salt to the plant until it reached the primary screener which was capable of screening 600 tons per hour of material.

The entire screen plant which covered almost 2 acres in steel work and weighed over a thousand tons with the steel and equipment
started shaking because the salt reached the 8 by 14 screener and the screener was not isolated from the frame work and almost knocked people off their feet.


The screen was overloaded and was properly mounted per the mechanical engineers drawings.


The screens orbit became larger and larger and the resulting physical energy was transmitted into the steel work where if it was hung by wire ropes or coil springs or air bags it is ISOLATED and the mounting frame is suspended cancelling out the energy created by the screeners elliptical orbit created by the electric motor and eccentric weights on the shaker arms.



You will love this part


a bit of backound for the readers:


large screeners are typically suspended by wire rope, coil springs or air bags when sanity prevails and stupidity has no opportunity of intervening.


SOOOO the manufacturer of the screen was called and the Mine Engineer who was resposible for this mess asked them what can we do to stop the excess shaking since we have so much salt to screen per hour..........



Their attitude was "so what? " weld 10-15 tons of steel below the screener body to create a damper and cancel the machines overshaking!!!!!!!!

"The steel added under the tractor platform is only a damper and thats all it is". to create a damping effect and no0t solve the problem only prolong it.





continued-
instead of changing the mounting to isolate the screen frame from the screen plants steel work or reducing the loading to reduce the resonance their solution was to add mass and not cancel the problem
==========================================================

16 years later the same issues, the same machine, annual vibration damage and who knows how long the steel work will last as long as the planned 40 year life span of the screen plant as it is bolted to concrete pylons with no additional frame support.

 

[kuboman]

tractor vibration issues






The cylinder is compressing the diesel fuel being pumped into the head of the cylinder and exploding at the point it can no longer compress it any further and bang the power and exhaust cycle are done.


The timing is the timing is the timing the engine will fire in the order deterimined by the manufacturer fro that engine.

If you change the timing it will not burn in the order it was designed to fire in with relation to the cranks design and position of the lobes.


I ran into this with deisels of all manufacture while I was a deisel and hydraulics mechanic at the mine where I worked previously.

As long as the timing is properly set the firing order will be maintained and the faster the fuel is pumped into the cylinders, the faster the pistons will compress the fuel to the point it explodes that much faster.

everything works in unison and if the engine and valve timing which are intermeshed have to work as fast as the fuel is delivered to the cylinders

adding the fix all of mounting plates under the platform is adding mass to cancel the vibration somewhat and a quick fix to offer a fix for the customer when it is not required by simply adjusting the fuel volume delivered per rotation of the injection pump.

the broken fenders and cracked platforms are a result of most of this issue in my opinion



I hope to buy a new kubota in the near future FWIW as my wheel horse has a second hydrotransmission and is 19 years old

The quick fix of adding mass to th eplatform in plate steel adds weight and cancels out some of the vibration and their quick fix solution is no solution.

I have nothing to hide and nothing to gain by telling you this about these diesels or any other diesel and the physics is the same no matter the engine
brand.


The 3 and 4 cylinders can be smoothed out by readjusting the fuel delvery rate and its commonly done.

adjusting the valves and or timing will not solve this problem because the engine is balanced and in the proper firing order; and as I have mentioned in previous postings these motors are used in rice combines, rice planters,
portable light towers, pumps, generators, small construction machienry and fishing boats and they sold all over the world with fewer emmisions restrictions and smoother operation as the fuel delivery rate is increased.


I will post my screener story to fully expose this issue for you to fully illustrate it .

UHHHhh????? Better get a better understanding of an engine first.:confused2: How the ???? do you change the firing order.:confused2: In a diesel the fuel ignites at the moment of injection.

 

[leonz]

engine etc.

Leonz, curious if you have this particular tractor and solved the vibration by turning up the volume of fuel? The poster above referenced another person that says he has one and the dealer installed rubber mounts and adjusted the timing on the engine to solve the vibration.

You say it is the fuel delivery volume and the other says it is timing. These are two different things in my book (maybe I have the wrong book?). Timing in diesel engine is when the fuel is injected, volume is how much is injected. What I am missing?

not missing a thing its a simple pumping adjustment to add fuel volume

The valve train, pistons, fuel pump are all connected by the gearing and the fuel pumps- if the timing is chyanged the entire firing order is changed and NOT IN BALANCE.

As the valve train, crankshaft, lobes, pistons, and fuel injection pump are all in synchronus orbit they will work even with the smallest amount of compressed diesel fuel.

The lesser amount of fuel provides less power to the entire engine to push the other pistons and they are slower in reacting even though the fuel is being delivered equally; as a result the pistons are traveling slower and delivering the energy provided by the lesser amount of compressed fule which was pumped into the cylinder head, compressed burned and exhausted in the 4 cycle engine.

Like I said the two cycle would be better but you would burn more fuel and it would not have these issues.


deisel theory and practice are still the same 110 years later

WHAT GOES IN MUST COME OUT in this instance its going in slower and coming out slower and the engines do not have enough mass to deal with it and as they do not have better isolation like an air bag its always there.


The Massey 1100 tractors were big engines in their day and mounted into the transmission and rear end and the engines were balanced and the fuel load was balanced and if it was not the tractor would not have been a huge part of american agriculture as no one would have bought it if it had a vibration problem like this.


you can compress a small amount of diesel fule and it will explode just as easily as a larger volume of diesel fuel in the same engine cylinder as the distance of the piston will compress the fuel no mater the volume and it will explode

(THE SMALLER THE FUEL VOLUME THE SMALLER THE EXPLOSION AND LESS USABLE ENERGY DELIVERED)

which affects engine performance because its always lagging in power and the 2 or three cylinders behind it are still doing what they are supposed to do because of the gearing, piston position, and valve train -

Which are properly set and adjusted for the given engine

all the parts are doing what is asked of them; the fuel is simply being delivered in a smaller amount and the engine is starved for power as it is a direct injection engine where an indirect injection engine does not have thses issues as the unused fuel is pumped back to tank.

 

[leonz]

UHHHhh????? Better get a better understanding of an engine first.:confused2: How the ???? do you change the firing order.:confused2: In a diesel the fuel ignites at the moment of injection.

I worked on diesels for 22 years, no the firing order is not changed
the firing order is always the same unless its running backwards

the fuel delivered is metered in lesser volume by changing the fuel volume delivery settings to comply with the emmisions regulations as the engines do not have exhaust gas purifiers which would allow them to be set properly with no vibration isssues.

 

[keyman1808]

WOW I am sorry I posted this from another forum. Looks like I am causing some feather ruffling.

OK here is the thread from the other forum http://www.mytractorforum.com/showthread.php?t=150171 Maybe someone should question them a little more and get the answer.

 

[leonz]

UHHHhh????? Better get a better understanding of an engine first.:confused2: How the ???? do you change the firing order.:confused2: In a diesel the fuel ignites at the moment of injection.

no, fortunately it does not, as it would create a fireball through the intake side of the engine.


I have an excellent understanding of internal combustion engines in surface and underground operations. I simply stated that the fuel delivery is what is creating the excess vibration which is making the engine lug and hammer to explode what little fuel is pumped and being delivered and there is essentially a motor which is restricted in its ability to operate within its proper fuel settings to maintain the proper low idle which will also affect the high idle setting which will lag which explains why in some cases owners have hands that shake and the nerve endings are still attempting regulate themselves.


In my opinion if a dealer tells his customer there is nothing they can do, the customer should take his business elsewhere as the engine is operating below its normal power range due to the fuel settings being lowered - if anyones really worried that can be dealt with using a catalytic converter and run the prime mover at it normal setting as the exhaust will only contain carbon dioxide and water as long as the engine is in good mechanical condition and the engine is run hot to keep the purifier clean and clar of carbon deposits.

 

[kuboman]

Somewhere in this thread a question was asked about the injection timing specs on the B7800. Hopefully someone can answer that. I am interested to know if it is different than the B3200.

 

[leonz]

FWIW, the V1505 is a generator engine masquerading as a tractor engine;

The low no load idle is 800 rpm and the high no load idle is 3,200 rpm

compared to the 2,700 rpm set for high idle.



I was able to down load one of the V1505 engine performance scales, enjoy.:thumbsup:


I think it will shed a lot of light and shovel a lot of (*&^ out of the way.

 

[Verticaltrx]

Somewhere in this thread a question was asked about the injection timing specs on the B7800. Hopefully someone can answer that. I am interested to know if it is different than the B3200.

Yup, still trying to find out. I might call the Kubota dealer next week and see what the B7800 timing spec is.

FWIW, the V1505 is a generator engine masquerading as a tractor engine;

The low no load idle is 800 rpm and the high no load idle is 3,200 rpm

compared to the 2,700 rpm set for high idle.



I was able to down load one of the V1505 engine performance scales, enjoy.:thumbsup:


I think it will shed a lot of light and shovel a lot of (*&^ out of the way.

What does the -E3-D24 stand for on the B3200 engine model then? I assume it's a little different tune than that in the graph. The graph shows the V1505 as 34 gross BHP at 2700rpm, vs 32hp for the B3200. Interesting that the best fuel efficiency is at 2200-2400rpm though....

 

[leonz]

I tried to find the designations where I looked on
the Kubota engine site but I could not determine the
identification as it pertains to the engine.

The indirect injection pump has a wide delivery rate
for its frame size and the number of cylinders.


I dont have an engine catalog but a lot of Kubota resellers
have this information available.

its probably due to the tier 4 designation and the
restricted flow from the injection pump to comply
with the Tier 4 exhaust standards.

The fuel adjustment screw is lead sealed to prove to
the end user it is qualified for the emmisions standards.