Same problem on my 2008 600 sci, it happens with all mercs, I drilled a hole in my and tapped it. Now every 10 hours pull out the tap and drain it and put fresh oil in, every time i drain it has gas in there . This saves having to by the cheap a$$ pumps that are made in india for 2 bucks and marked up .

I thought they already had plugs in them?

he,s talking about another plug to drain the oil,,that one you have to do yourself

So it has a fill plug and no drain? great design.

Correct. So you have to remove it and turn it on the side to drain, or if you leave it in place you need to use a little siphon pump to try to suck it out.

I keep meaning to drill and tap a drain plug on mine, but always in such a hurry to get it removed and re-installed I never do.

I saw this pump in another post. Can someone confirm this will work on the 525efi?

http://http://www.autozone.com/autozone/catalog/parts/partsProduct.jsp?itemIdentifier=77698_0_0_&skuDesc ription=Airtex+Master+/+Fuel+Pump&brandName=Airtex+Master&displayName=Fue l+Pump&categoryNValue=14999999&sortType=&store=243 9&isSearchByPartNumber=true&fromWhere=&fromString= search&counter=0&itemId=78-0&navValue=14900078&filterByKeyWord=60932&productI d=77698&searchText=60932&categoryDisplayName=Fuel+ Delivery&parentId=49-0

I dont think it will. If you run the part number for the fuel pump used on the 525efi... you will see that it is used on only a handful of engines... mostly EFI and SC based systems. Not sure if its the GPM or PSI but...

If you desire to replace the mech pump simply use a Holley 12-454-11 (or more if you need) by re-using the main body of the existing pump (with armature), remove the 6-8 screws and mount the new diaphram assembly and outer housing with the Holley unit.
Works pefect...
Dave

I am pretty sure the airtex is the oem, but once you add shipping, costs pretty close to the same and you need to epoxy paint it so I just bought Merc ones to replace both my pumps this spring. One was a mess, the other not bad. Definitely a 100 hour max replacement cycle on these.

We got the 502 Mag Mpi year 1998-2000 without this stupid water/gass pump combo,
is this only electric presure pump enough for this motor?I`m afraid not, why cant Merc put a proper el pump on the blue motors and eliminate this old mechanical car gas pump in a bad combination with sea water pump?What happens if I skip the me:party-smiley-004:ch pump on my 525 and 500 EFI motors?Are they starving and burning up?Thanks
Bjorn.