355 Oil Change - dry sump empty when cold?

Rob -- If by "dry sump" you mean the oil tank, your result was "normal" for the actions you describe. If the engine is off for a long enough time, the oil will drain via the small clearances inside the high-pressure oil pump (even though it's not running) down into the lowest part of the engine.

 

Rob

What Steve said!

 

Rob,
This makes perfect sense, and why all those new 355 and 360 owners overfill the engine...they check the oil cold (which is measured from the sump, which is now empty!) and start dumping in oil...next thing you know, they are two or three quarts overfilled.

I have splashed a bit of oil while emptying the sump, but I am getting better.

 

There is a 355 owner who advertises on the internet a powerful wet oil vacuum; he uses this vacuum to syphon out all of the oil without opening any drain plugs.

It's an interesting theory, and I guess it works for him. YMMV.

Whatever its problems, you'd think that it would at least be a non-messy process.

 

If you think your 355 is bad Rob, try a TR. Same problem with no way to get your hand out of the way to the side quickly when you remove the oil tank plug (only direction you can move your hand is downward) -- except instead of a few quarts, 8 or 9 quarts come gushing out

 

Rob

been there, got the t-shirt.......oil everywhere, dropped the plug in the bucket..why does it always do that

going on from Davehanda's post, conversely another issue with checking the oil when not hot is that the thermostatic valve to the cooler will be shut and oil may well have drained from this giving a reading that is too high in the sump tank

 

Hi Rob,
Have you and I discussed this before?, seems like we have, I didn't do a search. Anyway if you only remove the sump plug you don't have to go to the trouble of messin' with that tank plug, because the oil will drain from the tank to the sump rather quickly after shut down. That is the reason you need to check oil level right after you turn off the engine in 348/355 cars. There was a comment on a thermo valve on 355 in the last post, the challenge cars do not have that valve only road cars. The other difference on challenge cars is the oil coolers, there are two vs. a single on the road version, these hold 3 quarts of oil and they can not be drained out unless you remove them and turn them upside down to drain them. If you drain your oil often this doesn't make much difference unless you are changing brands or wieghts of oil(even this may not be a problem depending on what rule of thought you follow). Regards, Vern

 

For the 348, does the oil cooler have to be removed to drain the oil inside, or will the two drain plugs (or an external wet-vacuum) get it out?

 

I agree completely!! It makes it even harder when you don't have lift, but we all manage somehow

 

No. and no on the 355 road cars also. The oil line is at the bottom of the cooler, most probably don't bother but on my previous 348SS I disconnected the lower line to drain the cooler you will get about a 1/2 quart that will not drain back to the sump. Also I remember that not all of the oil drained back to the sump on that engine you need to drain the tank on its but much less
of a hassle than on the 355. Mainly because of the tanks location on the car.
Regards, Vern

 

Thank you.

 

Rob,

What type of oil are you using throughout the different seasons?

 

Wow, this post made me breathe easy. Mine sat for 2 days on the lift before I finally popped the tank plug. When I did, about 1/2 quart came out. I thought "Oh SHEET!!! I was really low on oil! (I checked it not long ago...)

When I popped the engine plug, I got a bunch of oil, but it's hard to count the quarts out until you are done.

Looks like this is normal. Whew!

 

Ok, I've been using a Motive Power Bleeder for my brakes forever. And now they sell a vacuum for use when changing the oil. Bought one to use with the various other cars in the garage. Given what's been written here, how much use would it be on the 355 (street car and the Challenge)? I'm assuming that since the dipstick is in the tank, it'll only pull a portion of the oil out. Anyone wanna WAG what percentage that would be? 30%? 50%? 75%? It's just such a PITA removing the underbody panel without a lift....

Of course, this all reminds me of the 360 Challenge owner who, in the process of using a similar tool, would empty the dry sump tank, and then START THE ENGINE so that the oil pump would pump more into the tank...

vty,

--Dennis

 

Rob, I love ya but Steve, Dave and Brian will back me on this.

You really want to change the oil HOT so that any impurities (water, gas, silt, SILT?) are suspended in the oil. All of the recommendations from the factory are to change the oil warm, IIRC.

 

This came from Aeroengineman, and is brilliant (though I have not brought myself to do it). He bought a large hole saw, about 3" in diameter, then went to a "mail boxes" shipping store, and bought a shipping tube of the same diameter, which comes with two plastic end caps. Measured twice where he needed the hole for the remote oil sump plug and drilled the hole. The shipping tube cap plugs right into the hole perfectly. It has been a few years now, but it has cut his oil change time in half! He still has the other shipping tube cap waiting for me.

Dave

 

Good idea. My customers never wanted me to cut holes in their cars, though!