Air Filter idiot light at high rpms

[Shipwreck]

COVID-19 gave me the time to do complete maintenance on my 2002, L3010. I changed the primary air filter but not the secondary. I’ll get a new one tomorrow. Here’s my issue; at proper rpms for brush hogging my air filter light comes on. I removed both air filters and ran the engine with no light coming on. I then ran it with only the brand new primary filter and no secondary filter and sure enough my light comes on again. My air hoses seem fine. I’ve cleaned the radiator fins. I’ve blown out the new primary filter and the secondary. What am I missing? I sure could use some help. Everything I read says not to run the tractor with this light on. My field grass is getting long.
Thank you

 

[SidecarFlip]

Don't have a clue but I know one thing for certain, you NEVER blow out the secondary filter. Big no no. The primary filter you can but from the inside out and not over 35 psi.

 

[Dave_eng]

I have attached the spec's for the filter sensor. Its contacts close at negative 6.22 kPa.

6.22 kPa equates to approx 24" of water.

You can make a home made manometer out of a piece of clear plastic tubing formed in a U shape. I suggest each leg of the U be about 4' long.

Add some water so each leg of the U has 18" of water.

Select a size of tubing that will tightly fit over the end of the sensor when removed. Connect one end of the U shaped tube to the sensor. Insert the other end of the U into the intake where the sensor was removed.

Start engine and see what difference the water level is in each half. This is the H in the attached. H should be 24" or more if the sensor is turning on.

If H is much less than 24" and the light is ON then the sensor is defective.

SENSOR, AIR REST - ASSY INDICATOR 15831-11090 $55.05

Dave

 

[PoTreeBoy]

Are you buying genuine Kubota filters?

 

[GeoHorn]

I’d be a lot less concerned about blowing out a secondary filter and a LOT more concerned about running it with no filters at all. Sounds like a bad sensor.

(Despite the cautions about it, I’ve blown out my secondary and reused it when it’s still inside the chronological-service period. Can’t imagine why it’s OK to blow out a primary but not a secondary.)

 

[SidecarFlip]

I’d be a lot less concerned about blowing out a secondary filter and a LOT more concerned about running it with no filters at all. Sounds like a bad sensor.

(Despite the cautions about it, I’ve blown out my secondary and reused it when it’s still inside the chronological-service period. Can’t imagine why it’s OK to blow out a primary but not a secondary.)

if the primary is working as designed, the secondary will never need blown out. What I was told by my Kubota mechanic. I change my filters yearly anyway, inner and outer.

 

[GeoHorn]

It’s a fact that when I did blow the secondary out (on my tractor, on my RTV, and on my JD-powered compactor/roller) I’ve never seen anything to indicate any dust or dirt was in them, only in the primaries.