How Clean Do I Need to Make the Drain Plug Threads

[JerryBob]

I've always been in the habit of thoroughly cleaning the threads of the drain plug of any grit and debris that I happen to notice when I change it. It probably gets there when I remove the plug, and it may scrape the bottom of the oil pan.

But it dawns on me that this is probably a waste of time. Any grit that happens to make it into the pan when I put the plug back in, will probably get filtered anyway.

Is this correct? Do I need to worry about this?

 

[TrevorS]

It's important to clean the threads for the quality of the seal and also for reading the correct torque if you use a torque wrench to tighten.

Clean the female pan thread as well as grit can be in there as well.

 

[Eddie]

I just consider cleaning threads as "The right thing to do". I really like it when I can screw a bolt or plug into something with my fingers and not feel any binding. Just the way my dad taught me. Ed

 

[JerryBob]

Originally Posted By: Eddie
I just consider cleaning threads as "The right thing to do". I really like it when I can screw a bolt or plug into something with my fingers and not feel any binding. Just the way my dad taught me. Ed


Hearing the gritty sound when screwing in the plug is like fingernails on the chalkboard. I confess to thoroughly wiping off the plug and surrounding area before I even take it off. Maybe I'm not crazy after all.

 

[JerryBob]

Originally Posted By: TrevorS
It's important to clean the threads for the quality of the seal and also for reading the correct torque if you use a torque wrench to tighten.

Clean the female pan thread as well as grit can be in there as well.


I don't torque - I use the "two grunts and a f*rt" method.

 

[SuperDave456]

Drain plug on my 2002 Ford Taurus was cross threaded long before I got it.
No amount of torque is going to make it not drip.

I used to change the gasket out every once in awhile, being once every 2-3 oil changes.

However, I just got a rubber coated copper washer that is doing a better job than anything else I have seen.
Best $3 I've spent in a long time. Might even be a permanent fix.

That being said, I have thought about getting a self tapping over-sized plug before. Just never could break down and get one being worried about where all those shavings really go.

 

[KitaCam]

How clean?

It's either clean, or not....a tooth brush will clean the threads just fine...

Always use a new $1 crush washer if it is called for.

 

[y_p_w]

I've always done it. However, it occurs to me that I'm probably introducing lint to the threads via a shop rag or paper towel. Whatever is there is ridiculously small compared to what might happen. Mostly I'm wiping it of any dirt/oil caking on the end of the plug.

I guess the one concern is that maybe a little stuff recirculates if the bypass valve opens.

I haven't replaced my plug in 100K miles. I used to use a torque wrench to tighten the plug, but these days I figure doing it by feel is adequate. Haven't cross threaded a plug ever, so maybe I'm lucky.

 

[y_p_w]

Originally Posted By: KitaCam
How clean?

It's either clean, or not....a tooth brush will clean the threads just fine...

Always use a new $1 crush washer if it is called for.

Copper, aluminum, fiber, plastic, steel, or composite? Subaru specs a steel compression washer similar to the washer you see on a spark plug.

I remember my dad's '96 Regal. It had an integrated rubber seal on the drain plug. I figured I'd just replace it for him, and the replacement was the same except for a magnet.

 

[RF Overlord]

Any threaded part should be clean when assembled.

Having said that, I usually just wipe the drain plug off with a clean rag or paper towel, same as the filter gasket contact area, and the area on the pan around the drain. It's always dry when I do the next oil change, so it obviously works. Nothing high-tech needed here.

 

[Kestas]

The oil plug usually stays clean for me when I do an oil change. OTOH, when I remove the transmission pan, I make sure all those bolts are clean before putting back in. Grit in the threads is not good. It's worth cleaning the threads before reassembly.

 

[CELICA_XX]

Here is my routine:

1. clean the drain plug
2. pour 1/2 quart of oil through the motor, and let it immediately drain out

I know this is probably overkill, but I like seeing the clean oil pour out before I reinstall the plug.

 

[y_p_w]

Of course I clean it since that's just how I am. However, from the standpoint of whether or not it really helps, I doubt it. Anything that might already be there isn't terribly harmful, and any kind of grit or crud is going to be filtered out anyways if it's an oil drain bolt.

 

[TechnoLoGs]

Originally Posted By: JerryBob
Originally Posted By: TrevorS
It's important to clean the threads for the quality of the seal and also for reading the correct torque if you use a torque wrench to tighten.

Clean the female pan thread as well as grit can be in there as well.


I don't torque - I use the "two grunts and a f*rt" method.


For an oil plug I usually go 1/4 turn past when it snugs.

Spark plugs and oil filter, too...

 

[InvalidUserID]

I just grab the rag that I use to wipe the drain pan area that inevitably gets oil on it and wipe down the threads.

 

[demarpaint]

I wipe the area surrounding the drain plug really good before removing the plug. I clean the plug threads which are usually clean and allow the oil to drain. I wipe the area where the plug goes and the threads, which I've never found dirty. Then screw the plug back in.

 

[asand1]

Only if I drop it in the driveway. I place the plug on the ramp, standing on its head.

 

[KitaCam]

....and don't forget to clean the oil pan threads....