Genset oil change..easy job, yes? No!

smlranger · 06-13-2005, 04:19 PM

OK I sit behind a desk most of the day so was looking forward to getting some grease under my nails..got the Wix filter, 3 qts. Rotella 15W40 and set up for a 30 minute oil change on the genset.

Oil drain plug had other ideas. I noticed it was a 1/4" npt plug with a small 3/8" head..that just looked like trouble. Was careful to make sure wrench fit tight...could not budge the plug. Tried boxed end wrench, socket..the plug is rather soft so both slipped easily on the small head. So, I get the vice grips...destroy the head of plug but it does not budge (I sprayed it liberally with P-Blaster).

So, no other recourse but to drill it and use an easy-out. Even with that, I thought the easy-out would snap before the plug finally moved. Upon inspection, looks like last guy put some thread locker on it...perhaps permatex or something. It was hard and crusted on the threads. I plan to get a plug tomorrow with a larger head. Actually, I was surpised it wasn't an automotive type plug with a flange and gasket or O-ring.

OK, so I put the strap wrench on the filter. No way! Magilla Gorilla must have done the last oil change! It took the biggest channel lock pliers I had to loosen the filter..crushed it in the process...oil running into my arm pit. New filter installed, 3/4 turn after gasket contact per instructions on the filter.

Well, at least it will be a year before I have to do it again. I sure hope the cooling system flush and refill goes better.

smlranger · 06-13-2005, 04:19 PM

OK I sit behind a desk most of the day so was looking forward to getting some grease under my nails..got the Wix filter, 3 qts. Rotella 15W40 and set up for a 30 minute oil change on the genset.

Oil drain plug had other ideas. I noticed it was a 1/4" npt plug with a small 3/8" head..that just looked like trouble. Was careful to make sure wrench fit tight...could not budge the plug. Tried boxed end wrench, socket..the plug is rather soft so both slipped easily on the small head. So, I get the vice grips...destroy the head of plug but it does not budge (I sprayed it liberally with P-Blaster).

So, no other recourse but to drill it and use an easy-out. Even with that, I thought the easy-out would snap before the plug finally moved. Upon inspection, looks like last guy put some thread locker on it...perhaps permatex or something. It was hard and crusted on the threads. I plan to get a plug tomorrow with a larger head. Actually, I was surpised it wasn't an automotive type plug with a flange and gasket or O-ring.

OK, so I put the strap wrench on the filter. No way! Magilla Gorilla must have done the last oil change! It took the biggest channel lock pliers I had to loosen the filter..crushed it in the process...oil running into my arm pit. New filter installed, 3/4 turn after gasket contact per instructions on the filter.

Well, at least it will be a year before I have to do it again. I sure hope the cooling system flush and refill goes better.

Vet Man · 06-13-2005, 06:29 PM

smlranger, go to your local parts store. I got a filter wrench that fits the end of the filter. It fits tight on the rippled end of the filter, and has a nut to put a wrench on. Vet Man

Zimectrin · 06-13-2005, 07:09 PM

Lesson learned----

You are your own best mechanic...

Captain Bud · 06-13-2005, 08:31 PM

Vet man speaks words of wisdom, DONT TRY THIS WITHOUT A FILTER WRENCH.

The Shadow · 06-13-2005, 08:32 PM

Mine is due and if as and when I get my coach back from the dealer (it has been in for more than a month now) I'm going to do it myself as I did with my Onan gasser. Thanks for the tips since I can visualize myself in the same boat.

troth · 06-14-2005, 12:08 AM

I might add that "while you're in the neighborhood", crawl underneath and look at the genny mount frame bolts (usually four of them). Past posts revealed missing bolts, crooked bolts, loose bolts, and corroded bolts. The plated steel (grade 5) bolts are threaded into the aluminum frame of the genny. That means galvanic corrosion. Best fix was to remove one bolt at a time, wipe w/ NeverSieze, and reinstall.

dirko · 06-14-2005, 08:56 AM

Hi Ho: For what it's worth: Getting things unstuck is best done with an impact (not steady pull). If you don't have an impact wrench a hammer can often substitute. Have fun.

smlranger · 06-14-2005, 09:22 AM

Dirk:

Agree. However, my wrench and socket had already slipped on the small (3/8") head on the drain plug. At that point, using the impact tool would only spin the socket on the plug. Had I known this was going to be that difficult, I would have tried the impact tool first.

TerryB · 06-14-2005, 02:46 PM

The best way to remove the 3/8 square head drain plug is either using a 3/8 square socket or else a short 3/8 drive extension backwards. The extension is hardened and the female end will fit tight over the plug. This engine comes from Kubota with the drain plug installed and it is never removed by Onan. You can purchase a brass pipe plug with a hex head instead of square. Also be careful using a hammer on the plug as the oil pan is die cast aluminum and very thin except for the drain plug boss area.
Terry

smlranger · 06-14-2005, 04:13 PM

TerryB:

According to service records from previous owner, the genset had two previous oil changes. How did they drain the oil if they didn't remove the plug? Maybe use one of those vacuum pumps?

I've now installed a brass plug with 9/16' hex head. Should be good to go next time.

gunny · 07-02-2005, 06:43 AM

First time oil change on ours was a little challeging also. Plug was in real tight and the filter was reluctant to come off. Knew of a person in the generator service business who would use a thread sealant on drain plugs and tighten filters until he couldn't tighten them no further. Was no fun working behind him.