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Topic: Onan Diesel genset air filter (Read 172 times) previous topic - next topic
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Onan Diesel genset air filter

Yahoo Message Number: 16985
I need to replace the air filter on my Onan 5000 diesel gen set. The filter is a small rectangular deal that is part number 140-3351. My local RV store would have to order it ($36) and on Amazon I found two offerings $33.11 and $45.00 plus shipping. Does any one a cross reference for this small filter.I realize RV parts can be expensive but this could be worth a try.

Re: Onan Diesel genset air filter

Reply #1
Yahoo Message Number: 16986
I may be out of turn to say this, but I never use Onan filters as the
price is usually prohibitive. I use Wix filters and order them from
Discount Fleet Supply, I believe they are in GA.

You can cross over Onan filters to Wix online. I use the same filter
140-3351 but I have crossed it to a Wix 42434 at a cost of $4.36 each.
Don't remember about the shipping.

Many of the filters from this supplier are boxed at 6 or sometimes 12
but if it is something you use frequently, I just order the box of 6
or 12. If I only want 1 or maybe 2, I usually order from Rock Auto.

In order to help with shipping, I usually make up an order of 2-300 of
filters and just keep them on a shelf.

I have used this particular Wix filter without any problems as well as
Wix filters for all the other filters, truck engine, water/fuel
separator, transmission, gen oil and fuel.

The only thing I have noticed is that I saved a bunch of money and was
not held hostage by Onan.

Hope this is what you were looking for but if not just ask.


Re: Onan Diesel genset air filter

Reply #2
Yahoo Message Number: 16987
Good one Don.

I watch on EBAY for good deals on filters. Many of the sellers list OEM
number. But are selling Wix and other aftermarket filters.

Ron Hall

Re: Onan Diesel genset air filter

Reply #3
Yahoo Message Number: 16988
I get mine from my NAPA Auto Parts store. Just brought them the Onan part number and they had it in stock.

Ted Marriner

Re: Onan Diesel genset air filter

Reply #4
Yahoo Message Number: 16989
My NAPA store also stocks filters that cross over the Onan numbers. I believe they are just Wix filters in a NAPA box. A Wix diesel fuel in
line filter is a 33270, and the same filter in a NAPA box is a 3270.

However, at NAPA the filters are substantially more expensive that when I order from Discount Filters.


Re: Onan Diesel genset air filter

Reply #5
Yahoo Message Number: 16990
I want to thank everyone. I ordered the filters from Discount Fleet and I am impressed. How Amazon can ask $45 for the same filter Discount sells for $4.85 is beyond my comprehension. I removed the old filter and took it to a RV Center in Spokane and they could not find it in there system. The air filter the parts guy brought was a cylindrical thing that would never fit in the air box. To further confuse him I also had the gen cover with the model decal ?? Unless you are interested in trading a older coach for a new one, that place is a waste of time.

Re: Onan Diesel genset air filter

Reply #6
Yahoo Message Number: 16991
Amazing is it not?

Just a note, I had problems with the gen fuel pump and pulled the entire gen out. The fuel pump is located under the radiator with the fuel filter attached after the pump. Thought it should be before but it is not. I removed the pump and filter and rerouted the fuel supply and return lines to exit the gen in the top rear. I installed an in line fuel filter then an after market fuel pump at a location behind the gen where I can change the filter in minutes instead of taking hours to change it from the original location. I also discovered the power leads would not allow the gen to come completely out of the compartment without disconnecting the leads. I extended the leads, fuel lines allowing the gen to be removed completely from the compartment and run in order to check it operation. Since the gen does not have an oil pressure gauge or water temp gauge, I installed a gauge for each. At the same time, I replaced and rerouted the dip stick tube that ruptured. In all of these modifications, I used absolutely no ONAN parts.

Since Onan has been purchased by Cummins, they are repaired by Cummins dealers. I talked to one dealer/shop in KY and they clearly told me they didn't like to work on these little "devils". He said if they knew one was coming in for repair, they tried to work out in the field that day. I told them about the modifications I made and he told me if a unit came in that had been modified, they were required to return it to factory condition before making any repairs. Guess that kills any factory work for me.

Best of luck in your filter quest.

Re: Onan Diesel genset air filter

Reply #7
Yahoo Message Number: 16992
I often stop at Truck Stop oil type change places and they always have the filters for my diesel generator. Seems many diesel trucks have diesel generators and they need to be able to change the oil