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Topic: Filter Restriction Guage (Read 1093 times) previous topic - next topic

Filter Restriction Guage

Does your A/F restriction gauge work? Mine never has. All piping and duct from the A/f housing to the turbo are in good shape and tight, proper filter curently a WIX 42610 and cover gaskets. The gauge works if vacuum is applied at the hose.
Bruce, Linda, and Macy
Zoey RIP 1/20/19
1999 U295 40' build #5400
2017 silver Jeep Wrangler, 1260 watts of solar on top
Moving around the country

Re: Filter Restriction Guage

Reply #1 –
I've not seen our filter minder move under normal operation conditions. We have driven the coach about 18K miles. We replaced the air filter immediately after we bought the U295.

I can pull the hose at the air filter canister and get it to indicate a change by sucking on it. That is probably bad practice, but it told me the gauge works. I am assuming that the filter is passing filtered air with little restriction.

Folk with more experience may have better advice.
J D Stevens
1997 U295 CAI 36' Build #5085
2002 Subaru Outback
Motorcade 16869
Bellville, TX

Re: Filter Restriction Guage

Reply #2 –
JD,

Mine just turned red half way through the trip a couple of weeks ago. Seemed a bit sluggish even for 8500' altitude so I went back and checked it. RED. Good thing to glance at when you pull the dip stick. We take it down a lot of dirt/gravel roads so the rear filter plugs up in a few thousand.

Just in case anyone is wondering, the telltale does work.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Filter Restriction Guage

Reply #3 –
My filter indicator never moves much either, stays at about the mid position.  That is until today after driving in some rain.  Now it is about 3/4 of the way to red.  I will reset it and check again on a dry day.  There have been posts on this before that driving in the rain will cause it to move into the red.  Also that rain will turn the dust on the filter into a hard crust when it dries out.  Someone stated that the air filter works better at removing dust after it has had some use, and that replacing it is not recommended until it hits the red, at which time it will appear to be overloaded with dirt.   
Jerry Whiteaker former owner 96 U270  36' #4831 Austin,TX-Owner Mods LCD TV w/front cabinet rebuild - LCD TV bedroom - Dual Central AC, either can cool coach w 30 amp - Skylights at roof AC openings - Drop ceiling for ducting of AC - Shower skylight white gelcoat/wood/epoxy frame - Air Springs/Shocks replaced - 2014 CRV - 8K Home Solar - Chevy Volt

Re: Filter Restriction Guage

Reply #4 –
yes it supposedly does work better when a bit dirty but with my deflector over the intake area it does not get any of the crap that it used to and no water enters it either. I sacrificed a while ago a new filter just to prove to myself that what I had done was the right thing and when I took the filter out it was almost like new. That is after our trip last winter across Canada and down the eats coast of US into Mexico to PV and back up the west coast--18000kms. If there was a tablespoon full of dust that was it. Bonus was my back up camera was nice and clean all the time even in the rain.
John
Coachless, now use aircraft. 2003 Ford Travelair TC280 class C. Super shape. Just for 1 yr .
1994 Ford E350 ClassC,total renovation inside and out. Now sold.
2000 U295  36' Cummins 350 c/w Banks Stinger, Resonator upgrade,Solar, LED lites.Residential fridge with slide out pantry. Build 5674. Sold
ex 92 GV 022C ored Cummins. Sold
ex 95 GV240 cat 3116. Sold
2017 Mini cooper s & 2016 land Rover LR2 HSE  LUX.
jhaygarth@aol.com    SKP #130098
treat everyone as you would like to be.

Re: Filter Restriction Guage

Reply #5 –
The air intake on Foretravels is not efficient.  After putting a cold air intake on my 92 Dodge diesel pick up and feeling the increase in power and the increase in MPG, I took a real close look at the intake on my 96 U320.  I planned it out for some time and finally decided to cut a hole in the end cap and built a ram air set up using 5" exhaust 90's.  Results: a gain of .35mpg.  An increase in HP, maybe as high as 50hp.  Shifting points dropped considerably, it will stay in 6th gear @ 50mph.  Going over the grapevine pulling my jeep, not problem keeping up with traffic.  Perhaps 5 to 10mph faster than before.  I am no body person, but I managed to fiberglass it back to gether nicely It is screened and "Y" into 2 5" intake pointing forward with built in water diversion.  Seems to work out great, it's been in place for 2 years now.

Bob  96 U320

Re: Filter Restriction Guage

Reply #6 –
Bob,

Picture is worth a thousand words. Have any?

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Filter Restriction Guage

Reply #9 –
Hi Bob,
  Sure is good to see you post. I hope all is well. I like the results you have seen with the air induction mods. Now with this "in" air approach, and some of the other exhaust mods, by others here, we should see some impressive results. Thanks for the update. Are you still in Cal and Arizona?
Raymond
Raymond & Babette Jordan
1997 U 320
1998 Ford Explorer XLT

Re: Filter Restriction Guage

Reply #10 –
What provisions were made to keep out rain if driving in a torrential downpour?

 Water ingestion will ruin a filter element and if it gets to the engine, can hydro-lock the engine much easier than on a gasoline engine because of the much higher compression ratio.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Filter Restriction Guage

Reply #11 –
Quote from: wolfe10 –
What provisions were made to keep out rain if driving in a torrential downpour?

 Water ingestion will ruin a filter element and if it gets to the engine, can hydro-lock the engine much easier than on a gasoline engine because of the much higher compression ratio.

And hydro-lock bends connecting rods, even at startup. Very slow head gasket leak locked a new 8V-71 and bent one rod.
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Filter Restriction Guage

Reply #12 –
Many years ago daughter drove through some curb deep water in the Volvo with diesel engine. Curb deep water in Houston is not rare. The car didn't stall and she saw no problems. At dinner that evening, "Dad, there is some white smoke coming from the exhaust on the car." Next day I started the engine and drove the Volvo to the shop. Yes, there was some white smoke. It was indicative of two bent rods.  :'(

Same day wife drove the MB diesel through curb deep water. After I got the diagnosis on the Volvo, I called the MB mechanic and asked if I should bring it in. "Did the floor mats get wet?" "No." "It's OK. Don't bring it in."  :)

Air intake on the Volvo was low and near the front bumper. Air intake on the MB was high near the front grill. The location of the air intake can make a big difference. Don't allow water to enter the air intake.
J D Stevens
1997 U295 CAI 36' Build #5085
2002 Subaru Outback
Motorcade 16869
Bellville, TX

Re: Filter Restriction Guage

Reply #13 –
Quote from: wolfe10 –
What provisions were made to keep out rain if driving in a torrential downpour?
I was thinking the same thing about Bob's setup.  I have seen similiar set ups on tractor trailers, but the intake opening faces the rear and down.  I believe many of the transit buses like the  Gillig hybrid are the same.
1994 U225
build #4514

Re: Filter Restriction Guage

Reply #14 –
Ya, a forward facing snorkel, particularly anywhere near the roof where it can collect 36+ feet of water in a torrential rain may well serve as a water scoop.  Not worth the risk.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020