My Perkins powered M-F seems a bit down on power

[def38]

I have noticed lately that when mowing areas that were done without the engine governor having to go to the limit, requires more intervention by the engine governor. The Perkins runs and starts like new without wet stacking ever, no smoke at start, no black smoke when loaded and uses no engine oil. I routinely ad a bit of Diesel Kleen to the fuel. About 700 hours showing. I'm not the original owner so I do not know the service history (valve lash setting, etc.). I have changed the oil more frequently that specified using only Mobil Delvac 1300 15W-40 and a Wix oil filter. The air filter is new (50 hours ago) and clean. So what could be causing what I perceive is a slight loss of power? Does the CAV pump need service? Do the injectors need service? Would valve lash out of spec cause the power loss? Could it be fuel grade?

Diesel experts, what's your assessment?

 

[VroomVroom]

Fuel filter?

 

[def38]

Could be. I have not changed it since ownership about 70 hours. I will look for a quality replacement (I'll likely choose Wix) which I can order on line with free shipping.

Any other thoughts?

 

[K5lwq]

I would not rule out a problem with the mower.

Does your dealer have a dyno? Maybe they would see if it is close to specs.

 

[def38]

I would not rule out a problem with the mower.

Does your dealer have a dyno? Maybe they would see if it is close to specs.

The M-F dealer has no dynamometer and the mower bearings and belts are in excellent shape. When disengaging the PTO, it takes the flail drum about 15 seconds to come to rest. I think I'll set valve lash this coming winter. If that doesn't help, I'll remove and have the injectors serviced. Also, I'm going to remove and sharpen the hammer flails and weight check them for balance.

 

[Smokeydog]

Air filter?

 

[K5lwq]

The governor opening up a little more but you still can mow at the same speed as before is very little power loss. It could be just the hotter weather right now. You might notice an increase as things start to cool off.

One thing is certain, if there is a problem it will get worse not better. Then probably a lot easier to diagnose. Good luck!

 

[kthompson]

I would replace fuel filter and check air filter and if mowing a lot air filter are subject to quick clogging depending on what you are mowing. One thing you are not considering is you are getting more familiar with the tractor, mower and the area you are mowing. It is very possible you are taking wider mower cut due to learning how to position tractor to get full width of the cut. It is possible with summer heat and rain anything as heavy as ours has been this year really quick growing grass. We are not mowing our yard 3 times in 2 weeks and may yet end up twice per week due to how fast it is growing and yes our mowers are cutting heavy grass compared to normal. It could well be you have developed an ear for your tractor and equipment and are picking up on sounds now you were not before. Remember once had issue with a noise in a vehicle I could hear but shop could not find. Asked what should I do, owner of shop said turn the radio up a little. Was not long before noise lever of the generator was loud enough to locate the issue. lol

 

[BrokenTrack]

Most likely it is a clogged fuel filter.

At 700 hours, it would not be the CAV Fuel Injector.

 

[def38]

I'm also thinking that my grass/weeds/brush is getting thicker (the Buick hubcaps are pretty much gone now as are rocks and logs) thereby requiring more power to mow what was less dense last year. This means adopting a more frequent mowing schedule to keep things under control.