Stripped oil pan threads - Fuel Economy, Hypermiling, EcoModding News and Forum

Xist · 03-23-2014, 03:08 AM

Yesterday my girlfriend wanted to visit her grandparents nineteen miles away and I mentioned that I needed to change my oil, which we did for Bacon over there a few months ago. When I had the car inspected before purchasing, they told me that I had a few slow oil leaks, but as long as I checked the oil regularly, I should be fine, and I could repair the leaks myself when I had the time. Everything went fine when we changed the oil in Chorizo until my girlfriend noticed that I was already leaking oil. I guess that I should use my torque wrench, I do not know how accurate my idea of proper tightness is, but apparently I use The Force to know when to stop tightening, instead of using The Force to tighten.

Or a sonic screwdriver.

Apparently, an impact wrench is as appropriate as my sledgehammer.

A friend said that it is cheaper to have a shop change your oil, then they are liable for stripping the bolt, but what are the chances that a shop did this and did not tell the previous owner? It turns out that the pan is aluminum and the bolt is steel. Aren't dissimilar metals supposed to be avoided? Since the bolt is stronger than the pan, it easily strips the thread, although I showed my girlfriend the bolt for some reason. I did not see the aluminum threads on it, like the picture at: http://www.mtsac.edu/~cliff/storage/...lug-Repair.pdf

That page mentions Fix-a-Thread Plug Saver kit, but does not say much about it, instead explaining that you can use a Heli-Coil, although it may wear out, so a TIME-SERT would be much better, but he went and used an over-sized drain plug, which is what the guy at Autozone convinced me to do. I bought a "cookie tray" oil pan and put it under my car when I parked last night. This morning it had a six-inch puddle, but the dipstick still read full. I needed to run errands because my parents were coming down for Xistday tomorrow. I planned on riding my bike until my mother gave me a grocery list that just seemed too long. The leak seemed slow enough that I felt that I would be fine as long as I made sure that I was at "full" before going anywhere, but when I had a friend ask if I wanted to hang out, I asked if I could get a ride to the store.

Eric the Car Guy (on YouTube) said that over-sized drain plugs only make the problem worse and explained that there were still good threads behind the stripped ones, so if you got a bolt with the proper thread and cut it to be half an inch longer than the old plug, you do not need to do anything else.

Ace did not have the bolt, I could not find it at HomeDepot.com, and according to this picture:

The walls of the pan are thin and there are hardly any threads in the first place. They say that Honda has had poorly-designed oil pans for decades and instead of putting in another pan that will fail, they weld a nut behind the hole, as shown on the left.

So, once again, I am doomed?

I keep telling my girlfriend that it is okay, I have two cars.

She really likes using Bacon...

I have not really done anything yet, I have the over-sized bolt, but when I go to my sister's house tomorrow for Xistday I will see if I still have my jack stands there. When I came back from Germany I could not find several things and easily could have forgotten about much more. However, I did find a note taped to car speakers that I bought, but never installed, with a price on it, so my sister may have sold as many of my belongings as she could have.

If I do not have a better option, I will not drive, and on Monday I will replace my bolt with the over-sized one. Is it even feasible to remove my oil pan, grind down the back of the drain hole, and have a shop weld a nut onto it?

For the record, qwikvalve.com recommends re-tapping the threads to the next-larger size.

wmjinman · 03-23-2014, 03:40 AM

My girlfriend's car had a nasty dent in the bottom of her oil pan, and everything was so dirty, I wasn't sure there wasn't even a leak there. Her transmission went bad & we found a used one on-line. During the job, I had the mechanic who was doing it "fix" the oil pan while he had the engine out. He did a really nice job of banging it out & re-welding the part along the crease he thought might be leaking. Then he said he re-positioned the drain plug a little lower, so more will drain out when changing oil. It turned out really nice.

So, yes, if you're willing to go to the time & expense, the pan can be taken off and either a "backing nut" welded on behind it or other repair. You probably could tap it out to a bigger size too, but you better be careful the new threads are nice & straight. And also be sure to clean any metal filings out if you do that!

sheepdog 44 · 03-23-2014, 11:17 AM

Fumoto Valve | Qwik Valve™

look into into a fumoto drain valve.

Xist · 03-23-2014, 02:32 PM

Quote:

Originally Posted by Xist

For the record, qwikvalve.com recommends re-tapping the threads to the next-larger size.

Quote:

Originally Posted by sheepdog 44

Fumoto Valve | Qwik Valve™

look into into a fumoto drain valve.

It is entirely understandable if you opened my post, saw how long it was, and tried to escape before wasting too much of your life!

It is Xistday!

NachtRitter · 03-23-2014, 05:01 PM

Had the same issue with Helga; discovered that the drain plug threads where stripped when I did the first oil change. Bit the bullet & purchased a new pan and then installed the Fumoto valve so I don't run into the problem again. Needless to say, I do not have anyone else change the oil on my car.

Happy Xistday!

chumly · 03-23-2014, 05:36 PM

What in the world is Xistday?

user removed · 03-23-2014, 05:50 PM

Maybe his birthday?

If you are going to remove the oil pan for a repair. I would consider a pick and pull replacement.
They also make threaded inserts that should do the job if there is enough material for one.
I would never helicoil a drain plug. The threaded inserts are not like helicoils, just use some powerful threadlock on the insert (NOT ON THE DRAIN PLUG!). I usually tighten up the drain plug with a box end wrench until it gets just snug with little force. The I use a wooden handled hammer and tap the wrench with the wooden handle until it stops moving easily (maybe another 20 degrees rotation). This method allows me to reuse the aluminum sealing washer (or copper if it calls for that) probably at least 10 times before it needs replacing. If that soft washer is crushed badly enough to expand more than 10% of its original width then you are overtorquing the drainplug.

Be very careful with the oil pan bolts, probably 6X1.0 and they only need about 4-6 foot pounds of force or you will strip them. I use a1/4 inch ratchet and my middle finger to tighten them. 6 foot pounds ain't much and you should use a little silicone sealant if there is a gasket I put it on my finger andput just enough on to make thesurface of the gasket wet. If there isno pan gasketthe nbe very careful tightening it up. It takes even less force without a gasket, just enough to keep it tight.

regards
Mech

Xist · 03-23-2014, 08:42 PM

Yes, Xistday is Xist's birthday. I always find it strange how much attention-seeking behavior I have. You would think that I would have cut back before turning thirty-five!

I realized that if I used an over-sized plug or re-tapped a larger one, if my pan is as depicted in the first post here, there might not be any bung left, just half a thread in the sidewall.

Is the EX pan the same as the HX? I wasted too much time trying to figure out that one, but when I finally pulled up estore.honda.com and realized that I needed to search for "pan, oil" and not "oil pan," it showed 11200-P2J for the EX and HX, but 11200-P2E for the DX. A new steel pan is $114.32, but aluminum costs $254.37. Of course, nobody is telling me to purchase a new one.

There is an HX pan in Tucson (116 miles) for $75 and two EX pans in Mesa (6.1 miles) for $85. I would need to get 63.7 MPG and not value my time to break even driving to Tucson. So, I can purchase one for approximately $80 and drive approximately 61 miles each way for what should be a good pan, and then install a Fumoto Valve.

Or I could not plan on driving Chorizo, remove the pan, have someone weld on a nut, and then install the valve, which I would not necessarily need at that point.

What would I do with my old pan? If I can just weld a nut, it should be fine afterward.

When I bought the car, I was told that I had a leak in the rear-main seal. Would there be any point in fixing that at the same time?