Oil pan plug - striped threads.

Topic: Oil pan plug - striped threads. (Read 2785 times) previous topic - next topic

Oil pan plug - striped threads.

April 24, 2016, 02:13:04 pm

Had RVMobile Lube over this am to change the oil filters on the M11 and he advised that he unscrewed the M11 drain plug with his fingers. After the oil had drained he stuck his finger up into the pan opening and pulled out some threads. Evidently the pan is a composite material with aluminum threads that a steel plug goes into and it is striped.

No more threads. Last service at Cummins in Mesa,AZ. Overtightened plug I am guessing.

Have called Beau to see if this is something he can tackle in our CG spot. I understand that this has occurred before and FOT does swap out these pans and have them machined in a local shop to re-thread the pan.

Your thoughts, input would be appreciated.

I will also contact FOT tomorrow in search of a replacement pan.

Mays guess is that there is a torque requirement for this plug. Does any one know what it is?

Re: Oil pan plug - striped threads.

Reply #1 – April 24, 2016, 02:15:30 pm

There is an insert you can get at Cummins and it can be threaded into the hole. It is a common issue on M11s and it is why I put a drain valve in this coach after it happened last time on my coach.

Re: Oil pan plug - striped threads.

Reply #2 – April 24, 2016, 02:21:10 pm

Scott, had this same thing happen. Gillette, WY Cummings pulled the pan, sent it to a machine shop that welded a steel insert in to the Pan. I then screwed in one of the quarter turn drain mechanism. Problem solved and no one removes the drain plug.

Re: Oil pan plug - striped threads.

Reply #3 – April 24, 2016, 02:22:06 pm

Better than the Cummins insert (which requires you use a wrench to keep the insert from turning and unscrewing from the pan itself) is either Femco or Fumoto valves. Lots of discussion on the forum.

We installed one last year for the same reason. Beau should be familiar with it.

You do not want to know the cost of a new aluminum oil pan, and if you did, I would suggest pricing out multiple sources, including using Cummins Power Club membership for discount.

Re: Oil pan plug - striped threads.

Reply #4 – April 24, 2016, 02:26:46 pm

Is a Fumoto type valve something that I can install? We have a family thing this afternoon, so I won't be able to do further inquiry until this evening. Thanks for your input, everyone!

Re: Oil pan plug - striped threads.

Reply #5 – April 24, 2016, 02:38:13 pm

Quote from: Carol & Scott – April 24, 2016, 02:26:46 pm

Is a Fumoto type valve something that I can install? We have a family thing this afternoon, so I won't be able to do further inquiry until this evening. Thanks for your input, everyone!

The valve takes the place of the drain plug. You still have to put the insert in to get threads for it.

Re: Oil pan plug - striped threads.

Reply #6 – April 24, 2016, 02:42:48 pm

The drain plug on the M11 is steel and it mates to threads in the aluminum block.
Aluminum threads are very easy to strip if the rather large plug is not tightened with a torque wrench.

The drain plug threads in the block of my M11 were so badly stripped that on the first oil change I managed to keep the plug in by adding teflon thread tape to the teflon thread tape already there. I was not comfortable with wondering if plug would fall out, and it did drip some, so I decided to tap the hole larger and install a Fumoto drain valve.

I taped the drain hole to 26mm by 1.5 which is 1.0236 inch by 17 tpi. This had little more threads than the original 1 inch by 18 tpi hole. I then ordered a 1 1/8 inch tap and Fumoto valve. I tapped the drain hole to 1 1/8 by 12tpi and obtained perfect threads, so installed the 1 1/8 Fumoto valve. Now the aluminum threads are good for life because there is no need to ever remove the Fumoto valve.

The one concern I had about the drastic tpi change (from 18 to 12) was the strength of the threads. I researched engineering papers on thread strength and found that in aluminum, 12 tpi is stronger than 18 tpi. So why would Cummins use the non-standard 18 tpi rather than the much more common 12 tpi. It is much easier to obtain good threads at 18 tpi than at 12 tpi, particularly when using high speed equipment.

I may still have available for sale: M26 x 1.5 tap and M26 x 1.5 Fumoto drain valve.
I may also have for sale taps for M27 x 2 and 1 1/8 x 12.

Note that at some point in time the oil filter for the M11 changed from ANC threads to metric (my 1996 is ANC) and I suspect that the drain plug was converted to metric at the same time.

I will check my stock and post to this thread later.

Re: Oil pan plug - striped threads.

Reply #7 – April 24, 2016, 02:56:06 pm

Quote from: Jerry Steele – April 24, 2016, 02:21:10 pm

Scott, had this same thing happen. Gillette, WY Cummings pulled the pan, sent it to a machine shop that welded a steel insert in to the Pan. I then screwed in one of the quarter turn drain mechanism. Problem solved and no one removes the drain plug.

Curious how can you weld steel to aluminum?

Re: Oil pan plug - striped threads.

Reply #8 – April 24, 2016, 04:43:34 pm

Sorry to hear, seems very common - we had the same issue. For a short term fix, I used an expandable neoprene rubber 1 1/8 inch plug and safety wired it to each side of the pan bolts so we could get home. There was no leakage or seepage during the 2500 miles home. I will look to see if I can find the specifics on the part. There are 2 types of expandable plugs and I used the brass screw type versus the folding lever type. With the screw type, you have a t post that can be wired very securely across the pan just in case. Are all 320 m11 pans aluminum? Is it possible to use the steel one from Cummins? They quoted $873 for steel and 4 hours shop time at $140. The plug came from Petersen Products Company, pipe plug, plugs, packers, hot tapping part number 1432113 PLUG, MECH, T-HANDLE, RUBBER, 1 1/8" DIA. Good luck!

Re: Oil pan plug - striped threads.

Reply #9 – April 24, 2016, 05:29:04 pm

Yes they are all aluminum and the steel one has a sump that hangs down way to far to put on our coaches.

Re: Oil pan plug - striped threads.

Reply #10 – April 24, 2016, 07:32:44 pm

I have never had an issue with the ISM drain plug, it just takes being careful and use some sense. Have changed oil in my coach at least every 5,000 miles for the past 75,000 miles, no issues with anything.
Cheers

Re: Oil pan plug - striped threads.

Reply #11 – April 24, 2016, 07:40:03 pm

As long as the torque of 65 Ft. lbs. isn't exceeded there would be no problems.

Re: Oil pan plug - striped threads.

Reply #12 – April 24, 2016, 08:31:07 pm

You can't weld steel to aluminum. I usually tap the drain hole to a larger size and put in a larger plug or put in a steel insert with green
locktite so it will never come out and use a plug or follow Wyatt's idea which should be a great fix.

Re: Oil pan plug - striped threads.

Reply #13 – April 24, 2016, 08:36:26 pm

Quote from: Dave M – April 24, 2016, 07:32:44 pm

I have never had an issue with the ISM drain plug, it just takes being careful and use some sense. Have changed oil in my coach at least every 5,000 miles for the past 75,000 miles, no issues with anything.
Cheers

Dave, at 125k my plug stripped out at Cummins and they were the last one to change the oil prior to that too. I do not think you can say no problem when it will fail at some point due to the dissimilar metals used.

Re: Oil pan plug - striped threads.

Reply #14 – April 24, 2016, 09:12:33 pm

Some are luckier than others, or more cautious. Maybe

Re: Oil pan plug - striped threads.

Reply #15 – April 24, 2016, 09:44:01 pm

Thanks Folks for your input and support.

My master mechanic son says the metal threads that my lube guy pulled out was a helicoill. and is commonly used to tighten threads. He says that he uses them all of the time. (Never heard of them before.)

Cummins in Mesa, AZ changed the oil the last time and there was no mention of the helicoil core insert.

Beau called me back shortly after my post and he will come and visit in the morning. He feels that he can drill and re-tap the hole, put in a threaded plug that my drain plug will screw into. Nothing new to him.

PITA

Re: Oil pan plug - striped threads.

Reply #16 – April 24, 2016, 09:45:16 pm

Quote from: Carol & Scott – April 24, 2016, 09:44:01 pm

Beau called me back shortly after my post and he will come and visit in the morning. He feels that he can drill and re-tap the hole, put in a threaded plug that my drain plug will screw into. Nothing new to him.

PITA

With Beau on board, it is not a PITA

Re: Oil pan plug - striped threads.

Reply #17 – April 24, 2016, 11:29:16 pm

Scott, a Helicoil is not to tighten threads it is there to put some back in!! Said another way you drill and tap the old hole out to one that will allow it to be tapped to suit the Helicoil and then with a tool you thread the insert into this re-tapped hole and this will bring it back to the original sized threaded hole. You can go bigger with them but it all depends on the amount of material left to support the Helicoil. I used them going back to the 60's when we repaired transmission and gear boxes used on the Napier Deltic Diesel Engines we built in England. They have been around for a long time and are good and easy to do (when you know what you are doing)
JohnH

Re: Oil pan plug - striped threads.

Reply #18 – April 24, 2016, 11:42:55 pm

Quote from: John Haygarth – April 24, 2016, 11:29:16 pm

Scott, a Helicoil is not to tighten threads it is there to put some back in!! Said another way you drill and tap the old hole out to one that will allow it to be tapped to suit the Helicoil and then with a tool you thread the insert into this re-tapped hole and this will bring it back to the original sized threaded hole. You can go bigger with them but it all depends on the amount of material left to support the Helicoil. I used them going back to the 60's when we repaired transmission and gear boxes used on the Napier Deltic Diesel Engines we built in England. They have been around for a long time and are good and easy to do (when you know what you are doing)
JohnH

They work much better in a blind hole rather than a through hole. I have an insert set made by Caterpillar that was used for through holes.

Re: Oil pan plug - striped threads.

Reply #19 – April 25, 2016, 02:01:59 am

I had the same thing happen to me last year when I changed my oil for the first time. I didn't notice that the threads were stripped until I was putting the plug back in. After hand tightening I put a socket wrench on it and it just kept on turning. I posted on the forum about it and Wyatt responded with the method above. I purchased the tap from him and ordered the fumoto drain valve. All is well and I never have to remove a drain plug again. I just attach a drain hose to the fumoto valve and drain directly into my old oil jugs for a no mess oil change. As Michelle said you DO NOT want to know the price of a new oil pan! Thanks again Wyatt.

Re: Oil pan plug - striped threads.

Reply #20 – April 25, 2016, 04:17:44 am

The idea of a fumoto valve sounds good but doesn't that valve hang down? It's already tight down there. In doing a little research there are instances where the valve was hit by road debris an caosed alot of trouble.

I really appreciate the input on this problem. I would be in big trouble without you guys and gals. :-D

Re: Oil pan plug - striped threads.

Reply #21 – April 25, 2016, 06:54:48 am

Quote from: Carol & Scott – April 25, 2016, 04:17:44 am

The idea of a fumoto valve sounds good but doesn't that valve hang down? It's already tight down there. In doing a little research there are instances where the valve was hit by road debris an caosed alot of trouble.

A previous owner of our U320 installed a drain device (don't know the brand) with a small lever to rotates to drain the oil. It seems very secure and doesn't hang down far enough to create a clearance problem. I'm extremely pleased with the system.

Re: Oil pan plug - striped threads.

Reply #22 – April 25, 2016, 07:22:20 am

Scott,

We have the Compact No-spill drain plug http://www.nospillsystems.com/index.cfm

The compact drain plug is only .030" thicker than the drain plug that was factory installed on our M-11. Said another way it only sticks down .030" further than factory plug. The way it is built if you hit it and you have damage the factory plug would have done the same.

Pamela & Mike

Re: Oil pan plug - striped threads.

Reply #23 – April 25, 2016, 08:44:09 am

I've had both and I prefer the Femco.
On the M11 there are 'other things' that hang lower anyway. The Femco capped system is a low profile with nothing to catch on.

Re: Oil pan plug - striped threads.

Reply #24 – April 25, 2016, 08:47:00 am

That's a Femco drain valve.

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