I have a 300SDL with an OM603 engine. I was changing the oil last week and dropped one of the bolts that hold down the lid to the oil filter canister. I have the second of two bolts, but need both of them to prevent it from leaking.

Does anyone have an extra bolt that you could send my way? I live in Michigan, and will be driving up from Tennessee next week.

Thank you for any help.

Usually there will be studs that screw into the body of the filter housing and nuts that are used to secure the lid onto the housing. That is often done to prevent damage to the threads in the aluminum housing from repeated removals and retorquing into place.

It might be wiser in the long run to obtain replacement studs and a couple new nuts if you're planning on keeping the car. Around my part of the woods, TrueValue Hardware stores carry metric studs and the shouldered nuts for them, I'm pretty sure the original setup uses M8 1.25 studs but a check of the remaining bolt you have should confirm what is correct.

Thanks for the suggestion. I went to Ace Hardware this week and bought a M8 1.25 bolt and some washers. When I tightened it normally, some oil trickled out after the engine had run for a while. I had to really torque down the bolts in order to stop this oil leak. It seems that a lot of pressure builds up in this canister when you shut the engine off.

By the way, do you need to put a copper washer down on the long spindle of the filter lid to mate with the rubber seal on the top side of the oil filter? I didn't replace it, and perhaps that is why it leaked initially. I've always done this before and never had a leak when retightening the nuts to the filter canister lid.

Maybe this is why there was a leak, and not because I had a slightly smaller nut and washer from Ace Hardware.

Yeah, there is pretty high pressure over 3 Bar and it's a pretty large surface area of the cover, so it takes some torque on the fasteners to hold it down. I've never seen or used any copper washer on the lid's stem, don't think it would do any good either.

Leaks from the lid are almost alays going to be the gasket if it's not a new one, lack of proper torque on the nuts tha secure the lid, or less likely but remotely possible some damage or warping of the lid itself.

Just be careful applying torque if you're using a bolt rather than the studs, it is pretty easy to strip the threads out of that cast aluminum especially with large sized fasteners!