Engine Vibration

[CentralNC]

I spent about an hour yesterday checking bolts, tires, wheels, etc. I found 1 or 2 of the FEL bolts that were about 1 turn loose. I also tightened the lugs on a wheel that I had removed a few months ago to get a tire plugged. That same tire was about 20 lbs low in air.

I took it out and gave it a test run. I couldn't get it to vibrate at all. I drove it on the same hard driveway, in the same gear at the same rpms....no vibration. I tried all gears on pavement, gravel and dirt ... no vibration.

I am not sure if any of the small changes caused the vibration go away. It may have been the box blade that caused it previously. I am not certain but it is gone now.

thanks for all the help.

 

[jinman]

That same tire was about 20 lbs low in air.

My 'money' is on the tire. That low pressure allowed the sidewall knuckles of the tread to run on the ground. This is probably a blessing though because you just went over your tractor and tightened those things that could become problems in the future.:thumbsup:

 

[CentralNC]

jinman - I sure hope the low air pressure was the source of the vibration. I use the FEL very often with the bucket or a set of forks.

Question - The air pressure range for R4 tires is very wide (16 - 45 psi). I typically run 35 psi in the front tires, but maybe a higher tire pressure is necessary when using the FEL. I would be interested in knowing what air pressures others are using?

 

[IH3444]

Thankgoodness it was that simple.

 

[Eagleview]

If I rev the engine above 2000 the vibration is greatly reduced.

Doesn't seem to coincide with tire pressure , but glad you fixed the problem with something you did .

 

[Porkie]

Be aware, that if your TC is a 4WD, that low pressures will spin a tire right off of the rim.It will stay on the rim but loose all of it's air. This has happened to me a few times when I didn't realize that my tires were low. Low pressure was surely your problem since it does cause the whole tractor to vibrate. My AG tires when on asphalt, really vibrate a lot. If you have the HST, I don't believe that there is a flywheel to loosen up. There may be a starter ring gear but no flywheel.

Sam

 

[jinman]

I typically run 35 psi in the front tires, but maybe a higher tire pressure is necessary when using the FEL. I would be interested in knowing what air pressures others are using?

I run 35 to 40 because I have heavy loads on my FEL. If I put 40 psi in, I can be lazy and not recheck the pressure for 6 months instead of every month.

 

[jinman]

Doesn't seem to coincide with tire pressure , but glad you fixed the problem with something you did .

I would absolutely agree except for this remark:

I just noticed the vibration a few days ago when driving around my property. It is a funny harmonic vibration that occurs most noticably between 1500 and 2k rpm. If I rev the engine above 2000 the vibration is greatly reduced.

I get that vibration when driving on the loose gravel on the side of my road because of the tire knobbys. If he had said it was noticeable driving or standing still, I would agree completely that tires could not be the problem.

 

[CentralNC]

I did a little test to prove that it was the air pressure. I dropped the air pressure in the right front tire and drove it back down the same gravel driveway (box blade attached). The tractor vibrated again just as it did last week.

When I got back to my house I pumped that tire back up and did it again ... no vibration. I think the box blade on the back was amplifying the vibration, but it was the air pressure that was causing it. Driving with low air pressure in the field (no gravel) did not give the same vibration.

I do believe Jinman was correct. Thanks Jim!!

Thanks to everyone else too.

 

[Eagleview]

Gee I wish more people would come back with what they found so we can ALL learn from the input given . We hardly ever have feedback so none of ever know what was the correct answer , thank you .