On my coach the engine air intake is on the rear cap, centered at the top. As we do a lot of Nat. Forest camping that usually entail gravel and dirt roads, how is that location for sucking dust ? Kinda wish they had taken it above the roof, with proper water diversion of course.
Based on the discussions I've read and heard, the air intake location pretty much sucks (literally) on all diesel pushers. It's hard to avoid the problem of the engine ingesting the dust, dirt and trash being kicked up by the wheels. That's why it is ESSENTIAL that you keep a good clean serviceable air filter in place, and change it regularly.
I was lucky enough to have a PO who installed a K&N cleanable filter in our coach. My air filter vacuum gauge had reached about 50% last fall, so I bought a K&N filter cleaning kit and pulled the filter and washed it. I was surprised how easy the filter cleaning process was. When back in I took the coach out for a road test, and there was a noticeable increase in power.
Definitely not a fan of K&N. Have seen way too many problems with their use.
I've read various information indicating that K & N filters do not do a good job and will shorten engine life. I would never use one.
What is the best filter to use? And, what percentage on the vacuum meter indicates replacement is required?
Yup
Air Filter Minder plus K&N discussion (split from What did you do to your coach (http://www.foreforums.com/index.php?topic=22204.0)
K&N air filter (http://www.foreforums.com/index.php?topic=13013.0)
K&N filters are a good way to dust your engine. You won't notice the increased wear but it will just gradually get harder to start. Use the stock filter and put in a restriction gauge that reads in inches of water
(" H2O) or kPa. The allowable restriction is different for each engine. Here is the chart: http://www.donaldson.com/en/engine/support/datalibrary/053979.pdf (http://www.donaldson.com/en/engine/support/datalibrary/053979.pdf) Replacing the air filter with another stock paper element filter made a huge difference in power in ours.
Doubly important in a pusher as all the road dirt gets sucked up by the filter from the front wheels in a lot of models and will require more frequent servicing. Later models are much better with the air intake up at the top of the coach. Some U280/U300 are especially bad with air cleaner intake down low right behind the rear wheels.
Pierce
Yep, I have one of those 280's. Also have to remove the antifreeze filter to get the air filter element out :(
For whatever its worth I threw away the K&N and went back to stock filter. Much better performance and I feel I'm taking better care of my engine..
X2 on the K&N filters. If you have room, they do may a good PRE-filter for your engine. Just install them right on your existing piping. Obviously, you need a restriction gauge. Some 18 wheelers have a forward facing scoop that eliminates most moisture from intake air while driving. That system possibly could be adapted, depending on your existing configuration.
TOM
I think ya'll are creating a problem that doesn't exist. Donaldson filters are used on everything from construction equipment (in super dusty conditions) to bus/RV. The air intake is in a good spot up high. Most filter assembly spin out much of the large particles.
If you really have a problem that must be solved, extend the intake pipe to the very front of the coach!
My present coach has a air intake scoop , on the co pilot side about 3/4 on the way up . It is on the side , not on the back end cap . I try to avoid dusty roads , but you can't avoid them all . I notice that I have a clean filter all the time , compared to previous coaches . They had the intake top centered on the rear cap . A very large improvement in location .There is a vacuum action caused by forward motion on our coaches that pulls the dust to that top centered intake . To observe , follow a coach or buss on a dusty road . That's how I noticed it . Brad Metzger
As most know I stopped water, dust etc from entering by putting on my Deflector at top of intake. Protects the camera as well. Filters last a lot longer now.
Rear Air Deflector (http://www.beamalarm.com/Documents/rear_air_deflector.html)
JohnH