[YOLO]

Does any one know the real answer? I have read 19 quarts AND 22 quarts. I'm doing an oil change on a pair and want to make sure I get it right

[Capt Keith]

I looked on boatdiesel and one of the spec sheets shows 6.6 gallons (25 liters) for the 3126 (355mhp, 350bhp). If it were me, I would find the serial numbers and CPL for the motor and call Caterpillar to verify.

[YOLO]

Thanks. I'll make the call. I also need to re-up with boatdiesel.com

[Capt Keith]

So how did the oil change go? Where you able to find out the actual oil capacity for the CAT 3126?

[YOLO]

Yep, the engines are a bit older and 22 quarts was the recommended. In 2007 (I think it was) there were some changes made and owners were getting excessive blow by so Cat revised it to 19 quarts.

[Capt Keith]

Thanks for the follow up.

[tankman2]

I would suggest trying 17 qts. plus be sure to fill the oil filter to "prime" it. Then check the stick after about 2 minutes to let the oil run down. If it needs more add a qt. at a time until it hits the top hashmark on the stick. Then start the engine and run it for about 3 minutes and check for leaks at the filter. Shut it down and let it drain back into the pan for 5 minutes. Check the sticks again and add if more is needed to reach full level. Do not overfill!.