Problems draining oil from dipstick-GM Vortec

[Wakesurfection]

Hi I've got a GM vortec inboard engine (V8 340HP 5.4L). There is no drainage hose from the bottom of the oil pan so I've got to drain the engine oil through the dipstick. I'm using a Mityvac 7400 and have inserted the smaller tube into the dipstick. Ive driven the boat around before I try and pump out the engine oil. However, no oil comes out when I pump the Mityvac. When I look at the dipstick, it doesn't go all the way into the oil pan. The dipstick seems to go into the engine block just above the oil pan. Any ideas how to drain the oil?

I've asked Mityvac and they've said it may be because the Mityvac tube is curling the wrong way. Is that right and has anyone experienced a similar problem when they've used a hand pump?

Regards

 

[Brybo86]

is there a garden hose thread on the top of the dipstick tube? typically those inboards do..., put your mouth on it and suck, you should feel resistance because the tube goes all the way to the bottom of the oil pan

 

[Wakesurfection]

Thanks brybo86 - no garden hose thread on the dipstick

any other ideas

 

[Wakesurfection]

I noticed that the dipstick starts off straight but then goes into the engine block just above the oil plan at a 45 degree angle. I've pushed the Mityvac 7400 hose all the way and its longer than the dipstick. I can hear the hose rattle about in the engine block but it doesn't suck any oil. It pumps out automatic transmission fluid from the transmission without any problems so I think its a problem unique to engine oil. I know another friend tried to pump out the engine oil using a drill pump but he couldn't do it either.

 

[Brybo86]

my uncles merc 454 is the same as you are describing...

did u try and suck on the tube to see if there is resistance? or do u just suck air?

if there is resistance get a drill pump and a bit of hose, and duct tape the connection really good, then crank it around

 

[dr2152]

Try pushing more hose in. Mityvac is right in that when the hose hits the oil pan it can turn. My pump hose is in a foot longer than you would think you need before it starts pulling oil.