I'm looking for information on repairing stripped threads in the oil drain plug hole on an AC5000. I had a major "Oh ****!" today while changing the oil in my 2000 AC500. I overtightened the oil drain plug and stripped the threads in the hole. It sure didn't seem to take all that much torque before the threads let go, has anyone else had this trouble before? If so, how did you fix it? Can the hole be re-tapped? It looks like the bottom of the oil pan where the plug screw in is removable. Has anyone had to replace that part before? I know I can take it to my dealer for repair, but I'd like to avoid the labor charge if possible and fix it myself (of course that's what got me into this mess in the first place!) Thanks for any helpful info you can give...

 

From my experience you have 2 do-it-yourself options. You could drill out and re-tap the threads to the next larger size. This should give you something akin to what was there. The other thing to do would be to put in a Heli-Coil insert. That is basically a steel insert that is threaded. You drill a hole slightly oversized, and after installing the insert, you are back to the original size threads. As an added bonus, the insert is steel, making the threads stronger than they were before. They are available through anbout any reputable auto parts store, Carquest, Napa, Champion Auto, etc. They have been used for years to fix stripped spark plug holes in aluminum heads, so they should be plenty strong. Hopefully, they can get one in your size. Either way, I would use a new plug, as you never know if they got buggered too, or not.

 

I agree, Farmr123; also, if bas44 is REALLY lucky, there might be a third option; he might get by with a "first oversize" or "second oversize" drain plug, sold at auto parts and accessory stores (like "Pep Boys").

My suggestion: Check the drain plug assortment; some of the bigger plugs have "piggy-back" drain plugs, so you don't have to revisit the stripped threads when draining the sump.

Tree Farmer

 

you can take out the 4 bolts around the drain plug and change the plate and while your in there clean the oil pump pick up screen its no big deal.

 

Or, you can go to your local auto parts store and get an expandable rubber plug that will work just fine. They work similar to the old type of thermos plugs. You put it in the stripped out hole and tighten with a wrench and the plug swells to fit the hole by compressing the rubber. They work very well, require no mechanical ability, and are cheap and just about fool proof. And as an added benefit they will not put any metal shaving in your oil sump.

 

I think I'd do it RIGHT. That'd be the way Frankd mentioned!

 

Thanks to everyone for the suggestions! It sounds like this might not be as bad as I first thought. Needles to say, I was not happy when it happened yesterday. I was picturing several hundred dollars of repair shop bills. I definately want to fix it right and would prefer to do it myself. While I'm not completely without mechanical aptitude, it's not my strongest ability.

I like the idea of the expandable rubber plug (thanks minehunter), although I am concerned that it might not hold with rugged riding, do you know anyone who's using one?

To replace the plate and clean the oil pump pick up screen (thanks frankd) seems like the best and most permanent way to go. I'm sure the skid plate has to come off first to get at the oil plug plate, is there anything in particular I should watch out for when removing that? Are any special tools, etc. required?

I also had a suggestion from someone today who thought an oversize self-tapping plug might work. I would think that might force metal filings into the oil pan. Any ideas on that suggestion?

Thanks again for your help!

BAS44
2000 AC500 Manual
400 miles since last spring and loving it!

 

You could use a screw extractor kit also. You drill a hole with a bit that is indicated on each screw extractor. Then, insert the screw extractor and it should come right out. It is really easy to use. You just go slow the first time and make sure you drill straight into the long axis of the bolt and is is easy. Jsut a thought if you ever have a similar problem and want to get back to the original sized bolt. (Hope I did not misunderstand your problem). If the threads that accept the bolt are messed up, you may try to re-tap it first.

 

I used one on a honda dirt bike back in the 70's for about 5 years. I lived in the Mojave Desert at the time and rode just about every chance I got. Never had a lick of problems with it.

 

i did the same thing about a year ago with my AC. i just got a oversized plug and used it. i learned real quick not to overtighten on warm aluminum.