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Topic: Oil pan plug leaking (Read 778 times) previous topic - next topic

Oil pan plug leaking

Changed oil in mt 8.3, new plug and gasket and it has a slow leak. The old one did the same. Any ideas? I cleaned everything well, never seen this before, sure don't want to drain it all out again. Not a bad leak, just a drip or two overnight
1996 U295-36, Cummins 300hp, 8.3. Build number 4864. Vin number 1F97D536XTNO54271. Purchased October 31, 2019.

Re: Oil pan plug leaking

Reply #1 –
Look for the posts about using a vacuum to keep the oil in with the plug out. Be careful to not strip the threads on the oil pan
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: Oil pan plug leaking

Reply #2 –
This is why Femco Compact oil drain plug is so popular.
And Femco is even more practical for aluminum oil pan with steel drain plug.
Prevention is the word of the day. . .

Re: Oil pan plug leaking

Reply #3 –
Maybe the face of the oil pan drain has a scratch on it and a file should fix it. I believe your oil pan is
steel so maybe be you could tighten it tighter.
Peter and Frieda Morin
1999 36ft. U320 Foretravel
Build # 5436
1998 Suzuki Sidekick Sport

Re: Oil pan plug leaking

Reply #4 –
Get a fumoto or femco and have ready, it's only going to get worse.
96 U270 BUILD 4810
85 380SL
Drummonds TN.

Re: Oil pan plug leaking

Reply #5 –
Would it be dumb to use thread tape (temporarily) on it.
Robert and Susan
 1995 36' 280 WTBI 8.3 3060r
 1200 watts on the roof, 720 Ah of lithium's
 Build # 4637. Motorcade # 17599
        FMCA  # 451505
        18  Wrangler JLUR

Re: Oil pan plug leaking

Reply #7 –
If it is leaking from the threads no matter what valve you get you will have to address that aspect,you'll need to clean the threads
so they are oil free and use a sealant that will work with oil.If you have to drain the oil again so be it,get clean containers and
put the oil back in.
96 U270 BUILD 4810
85 380SL
Drummonds TN.

Re: Oil pan plug leaking

Reply #8 –
I'll try some Permatex right stuff on it. It's a fantastic
1996 U295-36, Cummins 300hp, 8.3. Build number 4864. Vin number 1F97D536XTNO54271. Purchased October 31, 2019.

Re: Oil pan plug leaking

Reply #9 –
The threads on drain plugs don't seal, it's the gasket between the lip of the plug and the oil pan
that does the sealing.
Peter and Frieda Morin
1999 36ft. U320 Foretravel
Build # 5436
1998 Suzuki Sidekick Sport

Re: Oil pan plug leaking

Reply #10 –
Quote from: oldguy –
The threads on drain plugs don't seal, it's the gasket between the lip of the plug and the oil pan
that does the sealing.
And since there is a new gasket, there must be some scratches on pan plugs surface
2014 ih45  (4th Foretravel owned)
 1997 36' U295 Sold in 2020, owned for 19 years
  U240 36' Sold to insurance company after melting in garage fire
    33' Foretravel on Dodge Chassis  Sold very long time ago

Re: Oil pan plug leaking

Reply #11 –
The point is if you can get the threads clean and use sealer it will help with the leak,yes we know the gasket does the sealing.
96 U270 BUILD 4810
85 380SL
Drummonds TN.

Re: Oil pan plug leaking

Reply #12 –
Quote from: turbojack –
And since there is a new gasket, there must be some scratches on pan plugs surface

Ya, a couple of possibilities:

Pan sealing surface not smooth.
Pan plug sealing surface not smooth.
New gasket surfaces not smooth.
Improper plug torque-- either too little or torque affected by issue with plug or pan threads.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Oil pan plug leaking

Reply #13 –
Permatex Right Stuff on the threads and gasket sealed it up! No drips now.
1996 U295-36, Cummins 300hp, 8.3. Build number 4864. Vin number 1F97D536XTNO54271. Purchased October 31, 2019.

Re: Oil pan plug leaking

Reply #14 –
Yes. And I used the permatex stuff on my 8.3 timing case seal ( outside ) and so far so good.  Inverted a 5,000.00 repair bill from Cummins NW , at least for now.
Robert and Susan
 1995 36' 280 WTBI 8.3 3060r
 1200 watts on the roof, 720 Ah of lithium's
 Build # 4637. Motorcade # 17599
        FMCA  # 451505
        18  Wrangler JLUR

Re: Oil pan plug leaking

Reply #15 –
Cummins oil pans are aluminum and don't have that much depth so easy to develop a leak or strip. Aluminum pans are fine but need to be designed like Mercedes does on their pans. Ours has at least an inch of thread so stripping is next to impossible.

But that's not much help is it? I would make sure the mating surface is flat so a washer will seal. But you will either need to drain the oil or use a vacuum cleaner if you don't want to or just changed the oil.

Our U300 has a Detroit 2 cycle and a steel pan but while I knew it would never leak, there is too much of a chance of a spill and a big black mess to clean up in the garage and on you. So, I ordered a quick drain plug for our Detroit. If the drain is on the side of the pan, you can use the kind that has a valve on it but If your pan's drain is on the bottom where it can be hit by road debris, etc, you need the kind that does not stick down much. With a quick drain/no spill drain, you can start and stop the flow without spilling a drop.

So, I took my shop vac and used duct tape to attach the hose to the engine's oil fill tube so there would be no vacuum leak when I turned on the vacuum cleaner and the hose could not fall off while I was in the middle of installing the new quick drain. With the vacuum cleaner on, I slowly removed the plug, checking to see if there were leaks, especially when the plug reached the last of the threads. There was none so I totally removed the plug and sure enough, it was sucking air into the pan and not a drop was lost. Naturally, it's much harder to file the pan's oil drain boss flat this way but I didn't need to do it on my steel pan.

So, make sure to order the correct no spill drain for your exact engine. Members here should be able to give you the part number.  Here are several Cummins quick drains: CUMMINS - EZ OIL DRAIN VALVES- THE EASIEST OIL CHANGE!. As you can see, you just use a fitting to attach a hose to and thread in into the quick drain. With the little valve handle, you can fill a gallon container, shut off the flow, use a different container and repeat as many times as necessary to empty the pan. No spill,  just pretty light (7 pounds) one gallon containers to put in a car to take to your auto parts recycle tank (if they have one) Many NAPA locations do.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Oil pan plug leaking

Reply #16 –
It appears that 8.3 Cummins have a steel pan. What Cummins have aluminum pans? Sorry about the misinformation.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Oil pan plug leaking

Reply #17 –
Quote from: Pierce & Gaylie Stewart –
It appears that 8.3 Cummins have a steel pan. What Cummins have aluminum pans? Sorry about the misinformation.

Pierce
ISM is a magnesium pan. Mine was at least triple the recommended torque, or it was glued in? Quick drain plug lives there  now proactively.