Threading a new oil pan drain plug - Time Sert Kit - PeachParts Mercedes-Benz Forum

JHZR2 · #1 10-14-2018, 09:10 PM

As soon as I got the 350SD, I changed the oil. And as soon as I saw the plug (non typical and took a 17mm), I saw that the pan was slightly stripped. There were a few threads but not a full set. The plug didnt want to tighten fully and I didnt want to force it. It held oil but I wanted to fix it.

I bought an M14 insert kit from Time Sert. Had this been a 617 Id just put a new pan. OM603 not so much. Cost me about $130 from Amazon.

I drained about half the oil out into a VERY clean container. The intent was to pour it back through the engine to help flush junk out. The rest I wanted flowing when the work was being done. I did this cold, so the oil was more viscous and drained slower.

All the parts have a square end. They recommended using a ratchet. My palm ratchet wasnt handy, so I used my old 1/2 that has the knurled top. It worked well.

Slowly worked it in and out, so the big bits could fall out.

Then you use a tool to carve a lip below that the insert will gauge against to set its depth and stop it from screwing in too far.

This reams out more material, but only on that small cutting edge. It is fairly foolproof as it is set to the size of the drill that removed the old threads.

After that, you tap the hole with their tap. Not sure if it is a special size or what. They do have a cover for the tap, which sits on the pan, to help ensure that the tap is absolutely straight. Didnt get any pictures of that, but it's much the same. Tap, in and out, slowly, flush the threads and remove the bits.

After that, you oil up the threads on the setting tool. Then screw an insert on. They are phosphate coated steel.

You can see how the insert creates that inner layer, and ends up sitting flush with the pan.

Apparently the tool and the setup of these inserts not only sets it flush, but also then expands the inner threads slightly so it's really stuck in there firmly.

That's it. I installed a long M14 (13mm head) magnetic drain plug from Kent. After I flushed a bunch more old and new oil through.

So, here's the issue....

As I was doing the initial drilling, I was going in a bit, out a bit. When I was more or less all the way through, the bit got fairly stuck. Maybe I wasnt perfectly straight, maybe there was too much debris, I dont know. I thought maybe it was galling, though I doubted it since there was so much oil. When I investigated in the hole, I noticed a ridge in the bore that I had just drilled out. I though the ridge was just where the drill bit perhaps stopped cutting, but when I touched it, the part was loose.

So now I have a small triangle of aluminum in my oil pan. I tried to fish it out, tried to flush it out, and at some point it ended up in the pan someplace I cant see. Its a long, narrow triangle, maybe 1cm on its base, and going to a long, narrow point, the length of the threads, maybe 2cm?? The pan still tapped very easy, and the insert set very easy, so the lack of material was not an issue for that; rather, its more of an issue that it's in my oil pan. How concerned should I be? Removing an OM603 pan is not an easy job, but neither is pulling an engine...