Oil changes for generator

[Wolfpack Fan]

Just looking for feedback from all. Our motorhome has an Onan Marquis 7000 generator. Since tailgating season is upon us, it'll be getting a fair amount of use. It's approaching 150 hours now and has been changed once by the dealer. I can't find the book that recommends the oil change intervals or what type of oil to use, so I thought I'd post here. I know a lot of folks should have some good info.

I was thinking of using a mile a minute rule or 60 mph. With this, 150 hours would equal = 9000 miles and changing every 50 hours would compare to changing a car every 3000. The gen is not seeing heavy loads during this time of the year. No ac use, just intermitent microwave and tv.

Change interval ? Best practices.
Brand of oil ? Personal preference. I like Amsoil but not the price.
Onan filter or after market ?
Type of oil ? full syn, para syn, regular.

Thanks in advance for all replies.

[hardy1000]

Quote:

Originally Posted by Wolfpack Fan Just looking for feedback from all. Our motorhome has an Onan Marquis 7000 generator. Since tailgating season is upon us, it'll be getting a fair amount of use. It's approaching 150 hours now and has been changed once by the dealer. I can't find the book that recommends the oil change intervals or what type of oil to use, so I thought I'd post here. I know a lot of folks should have some good info. I was thinking of using a mile a minute rule or 60 mph. With this, 150 hours would equal = 9000 miles and changing every 50 hours would compare to changing a car every 3000. The gen is not seeing heavy loads during this time of the year. No ac use, just intermitent microwave and tv. Change interval ? Best practices. Brand of oil ? Personal preference. I like Amsoil but not the price. Onan filter or after market ? Type of oil ? full syn, para syn, regular. Thanks in advance for all replies.

I have the 8000 and the manual say's to change it every 150 hrs. Here is my manual but there are several models listed, one could be your model.

[Wolfpack Fan]

Thanks for the manual!

[stearn]

I have a smaller Onan. I found NAPA carries air,and oil filter. I took in the onan numbers and they crossrefrenced them.

[lllkrob]

My experience has been the OEM Onan filters are less expensive than the aftermarket. They can be purchased online at : www.cumminsonanstore.com
I change the oil every 150 hrs. and use 10w40 whatever oil.

By the way, your calculation should be 40 MPH X 150 hrs = 6000 miles. This is the rule of thumb used by OEM manufacturer's engineering departments.

[Benny367]

Quote:

Originally Posted by Wolfpack Fan Just looking for feedback from all. Our motorhome has an Onan Marquis 7000 generator. Since tailgating season is upon us, it'll be getting a fair amount of use. It's approaching 150 hours now and has been changed once by the dealer. I can't find the book that recommends the oil change intervals or what type of oil to use, so I thought I'd post here. I know a lot of folks should have some good info. I was thinking of using a mile a minute rule or 60 mph. With this, 150 hours would equal = 9000 miles and changing every 50 hours would compare to changing a car every 3000. The gen is not seeing heavy loads during this time of the year. No ac use, just intermitent microwave and tv. Change interval ? Best practices. Brand of oil ? Personal preference. I like Amsoil but not the price. Onan filter or after market ? Type of oil ? full syn, para syn, regular. Thanks in advance for all replies.

Just a bit of advice; If you intend on changing the generator oil and filter yourself then you'll want to make sure to purchase the Onan oil filter wrench since the oil filter is not accessible using a traditional band type oil filter wrench (only the end of the oil filter is accessible from the bottom of the generator and you need a cap type oil filter wrench)

[SRT]

I change my generator oil about every 150 hours. Use Amsoil 10W-40 and a NAPA gold (can't remember the #) oil filter. Guess I should check the hours today when we winterize the rig. Yes, summer is over for this year and the temps are going to drop 20+ degrees by Friday for highs in the upper 40's and lower 50's.

[chasfm11]

I'd second the cap type filter wrench. My filter is also almost inaccessible without it, though ours is a propane, not a diesel generator.

I've priced Onan parts at several different sources. Cummins Southern Plains, our local distributor for Cummins/Onan parts is cheaper than any of them, including O'Reilly and NAPA. I like the fact that they have always had all of the parts in stock, too. The gas to pick up parts from different suppliers would chew up any savings on an individual part or two. I'm as fussy about changing the air filter as I am the generator oil.