Merc 525 Oil Change
 

Can anyone tell me if the Mercury Racing 525 (or any other Mercury Racing I/O) engine has an oil drain hose as OEM standard equipment (similar to the Ilmor pictured) or if one must change the oil the old fashioned way by removing the drain plug in the oil pan? Pictures are welcome & greatly appreciated.

Re: Merc 525 Oil Change
 

Pump it out through the dipstick hole.The good pump is about $200.I have them on my 525efi's and they leak at the swivel 90 attached to the bottom of the oil pan.

Re: Merc 525 Oil Change
 

525EFI and the 496 varieties come with the Oil Drain hose factory installed. The 600SCi probably has one as well.

Re: Merc 525 Oil Change
 

Yes, it,s connected to the bottom of the oilpan and pumps out pretty easily.

Re: Merc 525 Oil Change
 

West Marine has a slick oil removal pump that literally sucks the oil out thru the dipstick. You pump about 8 times and watch it draw out the oil. It has an automatic shutoff when full. I love mine. it was around 90.00.
Check it out.

Smitty

Re: Merc 525 Oil Change
 

My 525 EFIs have the oil drain hose factory installed.. My boat builder attached these to plugs in the transom so that I can drain the oil from outside the boat. Makes it really easy

Re: Merc 525 Oil Change
 

my 525 also has the hose that comes out the hull plug hole. works great just put it in a jug and walk away.

Re: Merc 525 Oil Change
 

Thanks for the info guys. Can anyone tell me what is is on the end of the hose? The Ilmor has a brass -6 female flare hose end w/ a -6 brass plug in it. I have put together an Ilmor Oil change kit that I'm going to make available to others but wanted to see if I could offer more than 1 application increasing the value & versatility instead of offering 2 kits. One kit w/ the neccesary fittings to accommodate Ilmor & Mercury Racing applications.

I'm embarrased to have had to even start this thread w/ as many 525's I've looked at over the years but I've never owned one nor looked close enough to really know. I was hoping to get by the Extreme Marine this weekend & never made it. They have several DCB's & Fountains w/ the Merc packages.

Re: Merc 525 Oil Change
 

I have the 525efi and I have not found the drain hose. How long is it and where do they tie it up?

Re: Merc 525 Oil Change
 

On the 496's the hose is about 3 feet long. You can see it coming out of the pan in this picture. The other end stays clipped up near the intake. I guess you can clip it anywhere you want.

Re: Merc 525 Oil Change
 

I'll have to look again this week end. I looked for it last time I changed oil and never seen it. I wonder if they were on all of them or if the rigger had to do it.

Re: Merc 525 Oil Change
 

Dave,

What's on the end of the hose? What keeps oil from coming out if the hose were to fall on the bilge floor? Like i mentioned above the Ilmor has a -6 female str ftg w/ a plug in it.

Michael

Re: Merc 525 Oil Change
 

On my old boat, the hose was as described above and it had a threaded brass plug fitting at the end which capped it off. It was also wire-tied to the bilge drain plug which made it easy to pull out. The only problem was that it took over an hour for the oil to drain, even when it was hot.

Re: Merc 525 Oil Change
 

It will probably be tie wrapped on the back of the motor where its very hard to get.Thats where mine was.Comes from merc that way.

Re: Merc 525 Oil Change
 

Looks like I'm going to have to look at a 496, 496 HO & 525 in person in order to be sure what the fitting size & thread type is so that I can include the proper fittings.

I have an inexpensive & simple way to speed up your oil changes. I can drain the oil in my twin Ilmors (approx 5 gals) in less than 20 minutes from hook up to clean up.

Re: Merc 525 Oil Change
 

It's a brass pipe plug, 9/16 if I recall.

Re: Merc 525 Oil Change
 

I've read about it taking a LONG time to drain but mine seems to drain pretty fast.

Re: Merc 525 Oil Change
 

I didn't know there was a drain hose, been pumpin' it up the dipstick. where does the oil go when you drain it out the hose, into the bilge? that wouldn't be good. which is easier??

Re: Merc 525 Oil Change
 

It's about 3 feet long so you'd pull the hose out the bilge drain hole and drain it into a collection pan.

Re: Merc 525 Oil Change
 

Dave is that 9/16 wrench size or pipe thread?

Re: Merc 525 Oil Change
 

Wrench size, I'm not sure about the threads.

Re: Merc 525 Oil Change
 

The kit on the 496HO has a brass fitting at the end of it that extends out the bilge plug hole. I don't use the bilge plug lanyrards attach the bilge plugs to the ends of the oil drain tubes, as I like to leave my bilge plugs out all the time, especially when trailering, and if they were dangling there, they would flop all over the place, and the hoses would work their way out. The ends of my hoses are clipped up near my power steering reservoirs.
When its time to extend them out the bilge hole, I insert a straightened coat hanger from the outside-in, with a piece of wire attached to it. Hook the wire to the end of the hose, and pull it back out of the bilge hole.

The brass fitting on the 496HO uses a 5/8 inch wrench on the hose fitting. The plug that goes into it uses square tipped and fits a 3/8 inch wrench.

I normally heat my oil up if the boat has been sitting, or pull the plugs on Sunday night after a weekend of running, and just let the hoses stay in a 5 Gallon jug for a couple days. The majority of the oil drains out in less than 30 minutes. I use Mobil1 15w50. If you are using a straight weight oil, it will probably take longer. I would not be interested in any type of pump setup to suck the oil out faster. Since the drain plugs are at the rear and lowest point of the oil pan, I also make sure that I have the nose of the boat up high, so all the oil flows toward the drain plug/hose.

Works great for me.

Make sure you pop a hole into the top of our oil filters too, to let them drain into the pan, and not make a mess when removing them.