Community Forums

Ken L. · 02-29-2016, 10:57 AM

I have an update. The piping from the closet through the floor to the Air Cleaner is complete. I will be working on the collector box today. I was wondering if anyone has history with the K&N dry Air Filter for this coach?
A few pics. Ken

wb7auk · 02-29-2016, 11:06 AM

They do not meet efficiency requirements the engine makers demand.

DrDaveMA · 02-29-2016, 03:03 PM

Ken, it looks like you have used a piece of 7" pvc as the input to the collector box did you find a 90 degree adaptor for the exterior vents or are you going to fabricate that also? What exterior vent covers are you going to use?

This looks like something I want to start once we get back home in April.

bcbowers · 03-01-2016, 07:24 AM

Ken,

You asked about the K & N air filter. I purchased one and used it for several months. I felt that power & mileage had improved slightly but never specifically proved it. One owner experienced engine failure requiring a $25K rebuild due to apparent "dusting". The use of the K & N filter has been brought into question because of that failure. The K & N company supposedly have a guarantee with considerable insurance backup although it's probably difficult to "prove" actual cause & effect in that situation. Personally, I decided to NOT take anymore risk and abandoned its use in my rig.

If you want to try one, I'll sell you mine for a good price.

Ken L. · 03-01-2016, 09:03 AM

Dr. Dave, It is a piece of 8" dia. PIP low head p.v.c. pipe. It has approx.
1/8" wall thickness. I am working on the intake adapter now. The new intake grills are Attwood 1488-5, if they have enough open area to increase the air flow. I don't have them yet, they say Wednesday ?? It looks to me like the original 3 louver grill has more open space than the new 5 louver grill I have on order. I sure hope this works. Ken
PS. I worry about those K&N filters myself. Many people use them and love them, but I have heard plenty Nay-sayers.

wb7auk · 03-01-2016, 09:32 AM

Those that love them either do not care or do not know the damage they are doing that someone down the road will pay for.

greenmachine · 03-02-2016, 06:51 AM

Art, I would make some calls before I would say they are bad. I have one on my Dodge Cummins with 350000 miles and hasn't blown yet. I checked with Dodge and Cummins before hand. I believe in synthetic oils also. It all works together. All my cars and trucks have K&N and synthetic oils and grease. If you don't feel that's right then your doing the right thing for you. I have 74000 on the Alpine that I purchased and the oil was nasty and the air filter was just as bad. Anything I do is better than what someone else did. I purchased a full warranty because I was scared of what they did. I use Schaeffer Oils and it is brining all that trash out. I need to change again and it will be clean if its not leaking everywhere. What Ken is doing is the right thing and it will be on my list to do next. I have not seen the K&N filter for the Coach but I wouldn't be scared. I would call Cummins and go from there. Out here, Ford Diesel is better and Cummins is better and gas Coach is better and so on. Life is to short for that. I'm waiting for all the warranty work to be done on the Alpine. I think they are going to cover the fogged windows. Life is good
Thanks everyone
Larry Pate
2003 Alpine Coach 38FDDS 350 Cummins ISC

Old Scout · 03-02-2016, 06:59 AM

OK--anecdotal but several Alpines owners have reported failures with K&N air filters. Hard to believe that such a large company is having issues with a particular application of its product--however, reports of one failure is too much for me, so I'm staying with named brand, std filters, changed every 3 years--good luck.
PS--Still waiting to hear from someone who has already done this mod, about performance/MPG improvement from this considerable effort to "improve" air flow...

wb7auk · 03-02-2016, 07:07 AM

Quote:

Originally Posted by greenmachine

Art, I would make some calls before I would say they are bad. I have one on my Dodge Cummins with 350000 miles and hasn't blown yet. I checked with Dodge and Cummins before hand. I believe in synthetic oils also. It all works together. All my cars and trucks have K&N and synthetic oils and grease. If you don't feel that's right then your doing the right thing for you. I have 74000 on the Alpine that I purchased and the oil was nasty and the air filter was just as bad. Anything I do is better than what someone else did. I purchased a full warranty because I was scared of what they did. I use Schaeffer Oils and it is brining all that trash out. I need to change again and it will be clean if its not leaking everywhere. What Ken is doing is the right thing and it will be on my list to do next. I have not seen the K&N filter for the Coach but I wouldn't be scared. I would call Cummins and go from there. Out here, Ford Diesel is better and Cummins is better and gas Coach is better and so on. Life is to short for that. I'm waiting for all the warranty work to be done on the Alpine. I think they are going to cover the fogged windows. Life is good
Thanks everyone
Larry Pate
2003 Alpine Coach 38FDDS 350 Cummins ISC

Larry,

The standard set is 99.5% efficiency on diesel engines from the moment the filter is put in service.

Here is K&N's statement from their own web sight.

Our actual air filters when tested generally demonstrate a cumulative filtration efficiency of between 96% and 99%.

The words generally and cumulative are red flags.
You will notice their efficiency still does not get to 99.5% even after how many miles down the road?

Old Scout · 03-02-2016, 07:17 AM

Added point--When WRV went from 350 to mostly 400 engines, they also changed the filter and canister. Specifically, the alignment cone in the rear or the canister is larger on the newer canister. If you try to use the 350 filter on the newer 400 canister, the larger cone will hold the filter seal off the back wall of the canister--engine will be dusted. Either K&N or std paper, make sure you are using the correct filter size.

greenmachine · 03-02-2016, 07:36 AM

Ok, I'm sorry. I just talked to engineering Dept for Cummins Engine. They said that filter doesn't filter enough for the big engines. They use Fleetguard because it meets their specs. I explained about my truck and he said that filter is a different design than the one for the large engines. So he got in it deep so again I'm sorry so I will not have one in my Coach. He liked the synthetic oil but not the filter. Again I eat my words.
Thanks All
Larry Pate
2003 Alpine Coach 350 Cummins ISC

wb7auk · 03-02-2016, 07:41 AM

Quote:

Originally Posted by greenmachine

Ok, I'm sorry. I just talked to engineering Dept for Cummins Engine. They said that filter doesn't filter enough for the big engines. They use Fleetwood because it meets their specs. I explained about my truck and he said that filter is a different design than the one for the large engines. So he got in it deep so again I'm sorry so I will not have one in my Coach. He liked the synthetic oil but not the filter. Again I eat my words.
Thanks All
Larry Pate
2003 Alpine Coach 350 Cummins ISC

Larry,

I lost count how many times in my 70 plus years I have been there.

wb7auk · 03-02-2016, 07:55 AM

As a point of interest:

There is a filter out there called a Nanafiber filter that you see on some small engines that looks great but I was unable to find one that is built for diesel engines.

Ken L. · 03-02-2016, 09:29 AM

I am not trying to change this subject, I find it very interesting. As a point of interest, as I was comparing the new grills with the old one, I realized that what WRV did was remove two of the louvers from a five louver grill. Wa-la, THREE louver grill. So anyone thinking about this Mod. would only have to purchase 1 grill and do the removal, they are exactly alike, mounting holes and everything.

The framing in the wall is aluminum 3/4" x 1 1/2" sq. tube. The piece at the top and bottom run through to the rear of the wall leaving a space to the rear for the second grill to mount right next to the original grill.
So this is GOING to happen. If it is worth the "considerable" effort to achieve it will be interesting to find out. When I talked to the service manager at Cummins South Pacific, Colton, he thought more air would be BETTER, if it didn't cause the turbo to spin to fast, and he recommended that I go see K&N.
He said that their Filters and Intake Boxes worked great. He said that his Son had them on his Dodge and it was way better than his own Dodge???
So as is always the case it seems, Ford is better than Chevy and Diesel is always better than Gas, and on an on?????? Remember, we have these things for ADVENTURE! Later, Ken