The other day, I was changing the oil on my '88 740 wagon and everything was going normally until I went to tighten the drain plug back on to the pan. It felt unusually loose and wobbly, like the threads were stripped, so I unscrewed it and took a look at it. I figured and hoped that the threads on the plug itself were the problem, since it wouldn't be difficult nor expensive to throw it away and go get a new plug. Unfortunately, though, it turned out that the plug was fine and the stripping was occurring on the inside of the drain hole on the drain pan. The stripping wasn't too severe, so I was able to wrap a little extra teflon tape around the plug and get it tight enough to hold pretty well for now, but I'm not going to be too comfortable with it over the long run. My question is, is there any realistic way of repairing these internal threads, or do I have to replace the whole damn pan to get the drain plug to fit snugly? Thanks.

When we bought me wife's 1986 745T, the engine oil drain plug had been a victim of a pneumatic impact wrench turned up high. The oil drain plug would hold if it was wrapped in Teflon tape and tightened just right, but not too much. I could not find a satisfactory oversize plug. You will need to replace the pan. It is a complex job, but it can be done in under 3.5 hours. The 700/900 FAQ has great instructions on this written by Dick Reiss.

I've seen rubber plugs which can be inserted in the hold and locked in position. I've also seen drain plugs with valves on them for fast oil changes.

Pan replacement is probably the proper way to go and then he can replace his oil pump.
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Warren Bain - '99 V70GLT G-Valve > 70K mi, '96 965 >110Kmi Wifemobile near Manassas Va.. Check the 700/900 FAQ via the 'features' pull down menu.

If you find an oversize drain plug that works please let me know. My 940 has the same problem as yours. A previous owner or mechanic stripped the threads out of the oil pan and when I went to do the first oil change the drain plug wouldn't tighten up. The original plug has 19mm threads if memory serves. The local NAPA store had a universal plug that looks like a toggle bolt that folds up as you feed it into the oil pan and expands once it gets in side. Then the plug is tightened up by hand. I am using it as a temperary fix until an oversize bolt is found or a new/used oil pan is installed. Please let me know if you find a plug that will fix our problem Good luck, John

I havn't looked for these particular engines, but places like NAPA usually carry' oversized' oil drain plugs for most applications. they hve slightly heavier thread cut to stuff into messed up holes.
Quick lube places screw these things up all the time.

A friend of mine stripped out the threads on his 740 pan. He found an oversized self tapping plug somewhere (NAPA I think) that cuts it own threads in the pan. Worked like a charm and is still holding after a year or so.. May be an alternative to replacing the pan which is probably the really correct thing to do.

bl