I am curious how others change their oil. I am very anal about how i change mine,let me outline MY procedure and see if I'm nuts compared to others or maybe someone can gain insight from my procedure.
First off i have a 540 bbc thats blown and i get ALOT of gas and condensation in my oil. My pan is a 14 qt pan,my line are -12 and hold 1 qt,my filter holds 2 qts and my cooler holds 2 qts,(18-19 total). First i drain all the oil I can thru drain hose out bilge hole,i put hose in a 5 gallon pail and let drain for 5-6 hours. Next i change filter, then i put 6 qts in motor and crank over till it primes in 30 second intervals (to keep from killing starter)w/fuse out of fuel pump and coil dissconnected. I keep cranking over until pressure starts to drop from sucking oil pan dry. I then let the dirty oil that got pushed out of lines and cooler back into motor drain completely than fill with clean oil.I do all this because their is so much dirty oil in cooler and lines that i don't want mixed with clean oil,is this overkill or a good idea,Smitty

I just use the drain hose to suck the oil out. Leaves 2+ quarts in the Teague offshore cooler/lines. I don't worry about the remaining. At 50 hours I don't feel like am anywhere near the end of the M1 20-50's life anyway. With the accusump my system probably holds 12+ total.

I just use the drain hose also. I keep it changed every 20 hours, so like Wobble said I don't think the M1 is at the end of its life. There's no question your way is better though. BTW I'm running a 496 Mag with a Procharger.

Sounds like it takes a week to change the oil.When it drains from the bottom of pan then i would use a oil changer to suck the rest out from the bottom of the pan.sounds like it would work.

My boat is running rich still(I'm taking it to crockett soon and he's going to check the A/f ratio as installed while under way under boost and at idle) so my oil gets fueled up under 20 hours and looks like crap,holds great pressure though but i'm cautious. If i don't purge lines and cooler oil looks real dirty still after changeing it out.Smitty

I start draining it during a weekday when I'm not using it and usually let it drain overnight,finsh the next day after work,Smitty

Smitty- I think your procedure is very thorough. Just curious as to how many hours you run the oil before changing it? When you shut the motor off, can you smell gas on the dipstick? Does the oil level ever show higher after a run then before you fired it up? Just curious...Lou

I disconnect the exit hose from my pre-oiler and hook up another hose which leads to a five gallon bucket on the ground and flip the switch. In less than a minute my 14 quart pan is drained. Replace the filter and I'm done in less than 5 minutes.

I still have a couple of quarts in my Teague oil cooler and the lines, but I also use Mobil One and don't think it's a big deal to leave it there.

Sounds like you guys know what you are doing.

You can't smell gas in the oil but it looks thin although it still has 75-80 psi warm at wot.It doesn't gain oil from fuel,just gets contaminated looking. I ran this oil 12 hours but i changed it on vacation without getting old oil out of lines and cooler so it started out partially contaminated. Once i get computer re-mapped if tyler takes fuel out of curve anywhere i will stretch my intervals out to 20 hours. I'm leaving to go boating for next three days,I'll talk to you guys sunday night,Smitty