Air Filter Indicator

[Shadetree63]

Hello,
Put in a new air filter although the other one looked good. The air filter restriction shows 15 with a new filter? Is this about what the rest of you are seeing or is there a possibility that there is something blocked in the duct? I see where the PO had cut open the bottom of the duct, I assume he was looking for an obstruction?

Thanks in advance

[LJowdy]

There are numerous threads dealing with this subject. Here's another recent thread http://www.irv2.com/forums/f123/air-...on-458649.html

If you do a search, you'll find many more

[Gary RVRoamer]

Back to the original question, "15" seems high to me, an indication there is more constriction in the filter than is desirable. 15 is equivalent to about 50% on the minder scale. I would expect a new filter to read 20+ and drop back toward 15 and then 10 as it ages and gets more dirty.



However, my experience with the minders is that the scale numbers have no relation to reality and the most you can do is watch the trend. If your engine performs well on hills (where air intake typically goes to max), I'd consider that 15 to be your "Zero" and watch for it to climb past 11 toward the 8 (using the Baldwin minder numbers as an example). The filter probably needs replacing at that point.


The minder on my 2004 ISL engine ran between 22 ad 25 when the filter was new but by the time it reached 15 I could tell that hill-climb power was falling off. Time for a new filter. That's because the filter spec'ed for my chassis was right at the minimum size for an ISL 400, so any loss of filter capacity soon became noticeable. If I had a large filter canister, it could have gone longer.

[twinboat]

I think you have your numbers backwards.

The higher the number the more restriction the filter is creating.

Originally Posted by Gary RVRoamer

Back to the original question, "15" seems high to me, an indication there is more constriction in the filter than is desirable. 15 is equivalent to about 50% on the minder scale. I would expect a new filter to read 20+ and drop back toward 15 and then 10 as it ages and gets more dirty.



However, my experience with the minders is that the scale numbers have no relation to reality and the most you can do is watch the trend. If your engine performs well on hills (where air intake typically goes to max), I'd consider that 15 to be your "Zero" and watch for it to climb past 11 toward the 8 (using the Baldwin minder numbers as an example). The filter probably needs replacing at that point.


The minder on my 2004 ISL engine ran between 22 ad 25 when the filter was new but by the time it reached 15 I could tell that hill-climb power was falling off. Time for a new filter. That's because the filter spec'ed for my chassis was right at the minimum size for an ISL 400, so any loss of filter capacity soon became noticeable. If I had a large filter canister, it could have gone longer.

[Gary RVRoamer]

Your are right, twinboat. Brain fart, I guess.

Yes, it starts out low (8-11) restriction and grows over time toward 22-25.

[96 Wideglide]

Originally Posted by twinboat

I think you have your numbers backwards.

The higher the number the more restriction the filter is creating.

HA !

Had me second guess'ing if I really knew how these things work!

[Jyrocharlie]

I'm just going to drop this here too. It may be many RV's problem. Don't know.
What I found:
On my son's rv, the minder always showed red after it was driven, even with a new filter. We found out the opening on the side where the air pipe goes to the filter, is under size for the turbo airflow. It was causing enough vac during boost that the minder would turn red. We found it by removing the cover to the filter, the filter was still connected. The only thing disconnected was the lid. It eliminated the plastic pipe to the side where the air intake was. It had Never had as much boost and ran much better.
The RV was a 93 Gulfstream. The minder never turned red with the lid off.

[paddler1954]

I know this is kinda dumb but did you reset the filter minder after you changed the filter?

[Jyrocharlie]

Originally Posted by paddler1954

I know this is kinda dumb but did you reset the filter minder after you changed the filter?

Yes.