Oil pan drain plug...thread size?
 

In my 1996 Volvo Penta 7.4 Gsi, what is the thread type and size of my oil pan drain plug? I'd like to order an oil pan drain kit, that routes a hose out the bilge for oil changing, but have yet to determine the correct thread type and size.
Anybody out there know this obscure fact?

THANKS!

Re: Oil pan drain plug...thread size?
 

I'm going to be checking mine today for the same reason, I have a Volvo Penta 5.7 that uses the same drain plug as a '95 7.4 Gl,Gi,GSi. (3852694-3). Interestingly enough, I could not locate the exact part number for the '96 7.4's, but I would assume it is the same.

I'll post back what I find.

Re: Oil pan drain plug...thread size?
 

Thanks, Wooderson.
I could, of course, pull it and find out...but I'm looking to install an oil pan drain kit and want to buy one and have it ready when I drain the oil.

Re: Oil pan drain plug...thread size?
 

I checked mine today... I must admit this boat is new to me and this was my first oil change. Sorry to say I don't think the drain hose is going to work in these setups without some machine work. :(

The problem is that the Volvo drain plug is quite long and goes through a brass block before it screws into the oil pan. Look and the picture of the plug below. The area between the washers is where the brass block is. The threads into the oil pan are 1/2" x 20.

The brass block is where the dipstick tube is connected to the oil pan (beleive it!). I couldn't beleive it myself. Here's a crummy picture from my manual where you can kinda see in in at the bottom right. Sorry I couldn't get a picture of mine as it was sitting in my bilge attached to the dipstick tube.

Only way I can see to use the drain hose on this would be to drill and tap another connection into the brass fitting where you would screw the drain hose into... and I'm not sure there's enough material on the brass peice to do that.

Here's a link to the exploded diagram for a '95 7.4. 96 and 98 are the same. Couldn't find a diagram for the '97 though.

Assembly diagram

Re: Oil pan drain plug...thread size?
 

So, plan B, what is a decent quality, reasonablely priced unit for pumping the oil out of the dipstick? My dipstick mouth has the garden hose sized threads for connection.

Re: Oil pan drain plug...thread size?
 

Yeah, I was thinking the same thing.

I know this one is good from what I've read if you can find it somewhere:
http://www.shurflo.com/pages/Marine/...ge_winter.html

And I've seen this one mentioned as a good one too:
http://www.westmarine.com/webapp/wcs...llpartial/15/0

The good thing about using these pumps on this setup is that you'll get pretty much ALL the oil out of the pan since the dipstick tube connects to the lowest point on the pan. But too bad that these pumps are quite a bit more $$ than a drain hose.