vert

I am having a hard time finding any info on doing an oil change on a c320 using the drain method. Seems like most people use a pump to suck out the old oil, but I would like to drain it which is what I've been doing on my bmw for a long time. Couple of quick questions:

1) What is a factory specified torque on the drain bolt and on the filter cover in the engine bay? I would guess 18 ft/lb but would like to confirm.

Answer: Engine oil drain bolt torque = 30 Nm per MB shop manual. Oil filter cover = 25 Nm. Do NOT overtighten.

2) Sounds like people recommend changing the drain bolt crush washer or it will leak. The filter kit on my 330 comes with a new crush washer, but the filter I got for the MB does not include one. Should I get it at the dealer or do they sell stuff like this at Autozone for example? I know they are available online, but I need it now.

Answer: Dealer has them for around $1. Online place like autohausaz.com has them for about 20 cents each. Or can check another store for these specs: 14mm Copper Seal Washer 14x20x1.5mm

3) Where is the drain bolt located under the engine on a 2003 c320? I saw some people say that both the front and rear splash shields need to come off, but that was on a 230 I think. Just want to make sure I know exactly where to look for the bolt.

Answer: See picture in PCY's post for a 4Matic only. Follow the engine down to the lower pan and the drain plug is on the passenger side of the plan. Only the front splash shield needs to be removed to get to the drain bolt. Non-4mMatic cars have the bolt facing the rear of the car in the middle of the pan.

pcy

I have '04 C320, same as yours. I also drain oil via drain plug. I don't know the torque number for the drain plug. First I finger-tighten the bolt, then I turn half turn further. By then, the bolt is real tight. I replace the copper crush washer every time I open the drain bolt. I bought a pack of 100 assorted copper washer pack at HarborFreight store for $5. Individually, MB sells them for $1 each washer.

The lower panel under the engine (only the larger front panel) needs to come off to access the drain plug.

Red arrow in the picture below is pointing at the drain plug. Ignore the oil mess on that car. That is how it was when I bought the car - the oil was leaking from the oil level sender unit. Since then, I have had the oil level sender unit replaced and cleaned the entire area. Now, it's squeaky clean.

vert

A picture is worth a 1000 words for sure, thanks for that. When I bought my 330 the bottom of my engine looked like that as well due to a leaking oil housing gasket... I don't know how people can sleep at night with this mess down there

I'm sure someone must know the correct torque settings for the bolt and the filter cover and will chime in.

Xhale707

Yeah forsure man.. Clean up that oil leak you got going on PCY if thats your picture. Never seen anything that messy on a benz underside before.

Engine Oil Drain Plug 141 In-LBS or 16NM is what it should be torqued 2

vert

16NM or 141 In-lbs converts to 11.75 Ft/lb - that sounds pretty low for an oil drain bolt. What's the source for this torque number? Just wondering...

Got the torque for the filter cover?

Xhale707

Its not low thats what it should be mercedes work shop manual. The lock nut washer does all the work

Do not use a ft-lb torque wrench. Most foot-pound torque wrenches are not accurate at these smaller values. Make sure its set to 141 In-lbs

billbillw

I agree that torque number sounds awfully low and I'd double check it.

The spec for the M272 engine is 30Nm (or 22ft-lbs). I just don't see the torque being half of what the M272 requires, but I could easily be wrong.

Xhale707

Those torque values are for a Manual Transmission drain plug. I will repeat myself for the last time. Those are correct values i put.

If you think that is low. Your Automatic transmission pan bolts are 71 In-lbs and 8NM for the 722.6 Transmission. For the 722.9 Its 35.4 IN-lbs 4 NM and then you tighten an additional 180 degrees.

Please do not give out the wrong torque info if you don't know if its correct or not. Ive done the job many times.

The locknut washer does all the work.. If you over tighten it you will destroy the washer causing a leak

vert

Maybe that's the problem? I was asking about an ENGINE OIL drain plug torque, not the transmission drain plug. Could you look up the value for the engine oil drain plug in your MB shop manual? Also, they would probably list the the filter torque as well so if you can post it up that would be great!

PCY - is your picture for Engine Oil plug or Transmission Oil plug?

pcy

The picture I posted is showing the engine oil drain plug. You can't miss it. Just follow the engine down to the lower pan and the drain plug is on the passenger side of the plan.

You don't have to tighten the engine drain plug whole lot; the copper crush washer is there for a purpose...

FYI, Engine oil pan is [shiny] aluminum. Trans oil pan is black color.

Xhale707

The torque values i listed before are correct. To be honest my book doesn't say anything about the filter housing kinda odd. I know that on top of my filter housing the filter says 25NM. But when i do my oil changes i don't torque my filter I marked a line so i know where it needs to be every time. I only tighten it up to that line. I've heard horror stories on over tightening the filter housing. But then again im sure there are horror stories for anything you over tighten lol.

vert

Cool, that's what I thought. I asked because Xhale started talking about transmission oil drain plug so I thought maybe the picture that you posted looked like transmission to him

Xhale, since the torque you gave is for the engine oil drain plug and it is from the MB manual, I'll just set my torque wrench to 141 in-lbs when I tighten it. I was just confused when you started taling about manual transmission and automatic transmission torque values for some reason in your previous post.

BTW, I wanted to get the spark plugs for the 320 anyway so I ordered those from autohausaz.com (free shipping) and picked up 4 crush washers from them at under 20 cents each. They ship fast so i'll just wait a few days to do an oil change.

pcy

Handle ignition wires (spark plug wires) with care while removing them for spark plug replacement. Don't pull them out with force. Use 17mm open end wrench and leverage the wrench against the valve cover ... the ignition wire will come off with minimal effort.

Ideally start in the morning when the engine is completely cold, your hands will thank you.

Xhale707

The picture shown is incorrect. That is not how our engine pan looks. You will find that out because the bolt to remove it is on the wrong side.. It shouldn't be on the side it should be in the middle facing the rear end of the car.

Spark plugs. Im using 4 prong spark plugs i never had to put any crush washers on mine. Mine came with washers already i believe. I felt a huge increase in power after changing my plugs

vert

I guess I'll see when I get there... PCY has been always spot on in other posts though and 2003-2004 320s should be identical. And he confirmed that what he posted is a picture of an engine oil drain bolt.

Oh, in regards to spark plugs... I was just saying that i ended up buying the oil drain bolt crush washers since I was already placing an order for spark plugs anyway so the shipping was free. I bought 12 spark plugs and 4 crush washers for the next 4 oil changes.

I updated my first post with the answers you guys provided because this thread became pretty confusing for anybody who tries to search for this info later.

pcy

The picture I posted is from '04 C320 4matic. In EPC, the pan does look different for 4matic vs. non-4matic.

Vert, if your car is not a 4matic, then your pan will look like the one shown in the left side of the below picture. Part #41 is the drain plug.

billbillw

Look, I was just saying it sounded low and 30Nm IS for the oil drain plug torque on the M272, not the transmission drain. I take my info straight from Startek printouts that I've seen (I think Karo put these together).

http://i33.tinypic.com/dov1u8.jpg
http://i33.tinypic.com/2w3vt4x.jpg

You can't compare the tiny aluminum transmission pan bolts to a large steel drain plug either, vastly different thread strengths. BTW, its not a locknut washer, its a crush washer.

Is there anyone with STARtek who can look this up for the M112?

vert

Got it! Mine is NOT a 4Matic so it will be like Exhale described in the middle of the pan facing the rear.

I second billbillw's request - if someone can doulbe check the oil drain bolt torque for M112 in some official MB documentation it would help to put this issue to rest. On my 330i the bolt is similar, has the same crush washer and the recommended torque is 18 ft/lbs on both the drain plug and the filter cover, so 11.75 does still sound a little low.

Boom vang

I was told the correct way is to suck the oil out, that way I don't have to remove the undertray or worry about the drain bolt. The dealerships also suck it out of the dipstick tube. I use a 6.5 L Moeller fluid extractor pump which is quick, safe (no need to get under the car or risk of the drainbolt leaking), and free of any mess or drips.

http://www.moellermarine.com/afterma...id_extractors/

This pump is used throughout the marine industry and gets all the oil out as I am not ever overfilled if I add the spec amount of oil to my engine

vert

I am sure both ways have benefits, but I prefer doing it from under the car simply because I get to look around and spot any potential problems before they develop into something major, especially because the undertray is removed and the engine is naked. It's a personal preference and lets not start a war which method is better as there are plenty of threads on that.

I just want someone to confirm the torque numbers!

Boom vang

I prefer look at naked women than engines

My Haynes manual says 141in lbs or 16Nm which is 12 ft/lbs

vert

Awesome - so 16Nm it is. Very good to know as I would probably overtighten it based on my previous experience and higher torque values on other cars.

Does it say anything about the filter?

Boom vang

no specs are listed for the filter housing other than it says 'securely' Since there are multiple O-rings you don't usually risk a leakage if it is under torqued. However since it is plastic including the nut on top (for the 4cyl); you must use a filter wrench with a socket drive for the filter housing on a v6, just use caution and don't over tighten (snug but not super tight)

jspecteggy

I worked at a Chrysler dealer 2 years ago as a Tech and when we worked on the Crossfire to tighten the filler cover with the filter in it you hand tighten and turn it appx 1/4 turn. also idk if yours has it but when you get it serviced at a dealer they usually put a marking when they tighten the cover, i usually just go by that.

splinter

+1

Note aftermarket manuals (e.g., Haynes, Chilton, etc.) are often rife with errors.
Just wouldn’t be right to give a BMW pilot faulty intel on MBWorld.

Have been twisting wrenches for a while, but don’t recall using a torque wrench on a drain plug.
Probably just dumb luck none have ever stripped, leaked or vibrated loose.

FWIW, MB specifies 30 Nm for the M112’s drain plug: