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Engine Air Filter Testing

June 04, 2020, 05:41:51 pm

I learned something new at FT Service this week that might help someone.  When I do a regular maintenance check of my engine bay, I always check my Filter Minder.  Every 3 months I also take off the little hose to the Minder and suck on it to make sure the Minder is working properly.  I've done this for the 14 years I've owned the coach.
On my service checklist I asked the tech to check for intake air leaks and system integrity.  He came and found me in the Customer Lounge to tell me I needed a new engine air filter.  I told him he was crazy, since I had very recently done my Filter Minder test and everything was fine.  He asked me to accompany him to the shop, where he showed me my very plugged air filter.  Then he showed me the plugged 90 degree fitting on the end of the filter housing!  Yes, the Minder was fine.  The hose was fine.  But the fitting was plugged, so the Minder was non-functional.  He had to use high pressure air to unplug the fitting.  BTW, my filter was two years old and had gone 26,000 miles.  Have you checked your air filter housing fitting recently?

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Re: Engine Air Filter Testing

Reply #1 – June 04, 2020, 06:06:56 pm

Brett,

So, one not only needs to suck on the filter end of the hose to the air filter minder but also on the filter minder end to verify that the fitting on the filter housing is OK.

What in the world clogged that end-- never seen that.

The other Brett

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Re: Engine Air Filter Testing

Reply #2 – June 04, 2020, 06:43:48 pm

Reminds me of the first time I flew in a small Cessna and watched the pilot suck on the pitot.  Honk!

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Reply #3 – June 04, 2020, 07:45:53 pm

So inhale at both ends of the hose that runs from filter minder to air intake

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Re: Engine Air Filter Testing

Reply #4 – June 04, 2020, 08:12:45 pm

Thanks

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Reply #5 – June 04, 2020, 08:23:11 pm

Mud daubers aka wasps, hornets build mud nests everywhere they can on an RV. They love the propane water heaters, might like the air cleaner restriction gauge, HWH ports, etc. When something doesn't work that did on your last trip, it's something to check. They can sting more than once too.

Pierce

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Reply #6 – June 05, 2020, 08:03:15 am

Look on the inside of the air filter canister cover.  The hole that the Minder is sucking through is tiny.  Don't try to clear it with a probe.  Blast it with air from the outside in.  Talking about small holes,  My fridge stopped working on propane this week.  I found that the jet had been plugged my ONE spider.  Go figure.

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Re: Engine Air Filter Testing

Reply #7 – June 05, 2020, 08:49:42 am

Mud daubers aka wasps, hornets build mud nests everywhere they can on an RV. They love the propane water heaters, might like the air cleaner restriction gauge, HWH ports, etc. When something doesn't work that did on your last trip, it's something to check. They can sting more than once too.  This is true, But
Minder is sensing the differential from the inside of the air filter to the outside. The sensor port is in the clean side of the filter. Insects would have to be (inside) the filter to plug the port. Doubt they ever got past the filter. IMO Remove from Filter housing before its cleared to help prevent contamination on the clean side of the filter.
Scott

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Re: Engine Air Filter Testing

Reply #8 – June 05, 2020, 09:50:29 am

Yes, it's the clean side.  Remove the housing lid before you clean it.  I have no idea what plugged the fitting but I bet it took 20 years to do it.

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