Oil pan gasket

[Dan Hiebert]

I had been keeping the oil pan bolts torqued to what a table I use lists for 5/16-18, that being 17 ft. lbs.  Neither of my Dodge or Plymouth manuals list a torque setting for the oil pan bolts.  I've found I have to re-torque them every year without fail, or the gasket will leak, meaning 17 ft. lbs. in that oily and high-vibration environment won't keep them tight.  This year I torqued them all to 20 ft. lbs. and felt they cinched up better without mashing anything that's not supposed to be.  We'll see how that plays out.  In checking my manuals to ensure I didn't stick my foot in my mouth, they also iterate installing the oil pan gaskets a la Rick D's post, although there's no mention of pins or studs - those are lesson learned / common sense things. 

[Sniper]

9 hours ago, Matt Wilson said:

Talking about not over-tightening the pan bolts, I've always had the tendency to do just that, for fear that the bolts will come out if I don't tighten them enough.  Manuals that provide a torque value for these types of bolts state a really low value, like 10 ft-lbs or so, and that just seems like it will allow the bolts to fall out and oil leakage to begin or worse.  So if we follow the proper recommended torque, what keeps the bolts from coming loose?  Should some type of low-strength thread locker be used?

 

Excellent question.  Not so long ago I was under my 51 working on the steering.  For some reason, probably boredom, I decided to put a wrench on the oil pan bolts, they were all loose.  Might be a good idea to add retorquing to the oil change procedure.  Loctite wouldn't hurt either.

[Bob Riding]

On 6/3/2023 at 2:58 PM, 46BulldogDodge said:

Two suggestions...first, the straight pins should be snipped off to a half inch length and pushed into the side gasket and into the end gasket.  Just like a nail would hold a board.  When the oil pan bolts are torqued, that longer end gasket gets compressed in its track making a tighter seal.  Second, regarding sealing compound on the gaskets, others use grease on the block side  for easy removal of the pan at a later time and Permatex Red on the pan side.  Guide studs, as 9 Foot Box shows, make installation easier by lining things up while you're on your back under the car/truck.  I get by with using two studs at the diagonals while I finger tight a couple bolts.  Remove the studs as necessary and DON'T over tighten the bolts.

 

Final thought...before reassembly, check the pan surface is really flat.  Someone previously may have overtightened the bolts distorting the pan.  I use a round drift larger than the bolt's washer and tap the distorted hole perimeters back to flat.  I put the pan upside down on my tablesaw for a reliable flat surface.  

 

 

Dick Hultman

I just got this used oil pan from DCM Classics. It's in good shape except I can't tell if the surface is distorted at each bolt hole or that's the way it was stamped. What do you think?

[Bob Riding]

5 hours ago, Dan Hiebert said:

I had been keeping the oil pan bolts torqued to what a table I use lists for 5/16-18, that being 17 ft. lbs.  Neither of my Dodge or Plymouth manuals list a torque setting for the oil pan bolts.  I've found I have to re-torque them every year without fail, or the gasket will leak, meaning 17 ft. lbs. in that oily and high-vibration environment won't keep them tight.  This year I torqued them all to 20 ft. lbs. and felt they cinched up better without mashing anything that's not supposed to be.  We'll see how that plays out.  In checking my manuals to ensure I didn't stick my foot in my mouth, they also iterate installing the oil pan gaskets a la Rick D's post, although there's no mention of pins or studs - those are lesson learned / common sense things. 

here is the torque specs page from my '55-'56 Plymouth manual. 15 ft lbs for the oil pan bolts.

[Sniper]

10 minutes ago, Bob Riding said:

I just got this used oil pan from DCM Classics. It's in good shape except I can't tell if the surface is distorted at each bolt hole or that's the way it was stamped. What do you think?

 

 

I'd say it's distorted.  The pan rail needs to be flat.

[Plymouthy Adams]

that pan is in need of some tweaks to bring the sealing surface level and smooth...this is classic signs of over tightening trying to extend the uefullness of a gasket

[motoMark]

10 minutes ago, Bob Riding said:

I just got this used oil pan from DCM Classics. It's in good shape except I can't tell if the surface is distorted at each bolt hole or that's the way it was stamped. What do you think?

 

Looks to me like the pan bolts were over-tightened and deformed the pan. The gasket surface should be flat. I would flatten those bumps.

 

[kencombs]

Just lay a straight edge on the pan, front to back centered on the bolt holes.  It should touch the entire length.  If not, 'adjust' the pan'.  I use a piece of steel on the bottom and gentle hits with a small hammer on the top until each one is even with the pan's seating surface. that ,

 

I've used different things for the backup steel over the years, it just needs to fit into the pan seating surface from the bottom, not riding on the rolled edge.   Best fit is a piece of strap whose width is a good fit, maybe a couple of inches long.  Tack weld that to a heavier piece to provide mass if you don't  have a thick piec.

[Bob Riding]

The jury has spoken! thanks guys- I have some body hammers and dollies that should work.

[Dan Hiebert]

19 hours ago, Bob Riding said:

here is the torque specs page from my '55-'56 Plymouth manual. 15 ft lbs for the oil pan bolts.

Good info, thanks for posting this.  My Plymouth manual is 1946 - 1954.  It lists only 11 torque specs for the engine, which I've always thought was insufficient.   

[Doug&Deb]

Here is another question. My new Fel-Pro gasket includes 2 o-rings to fabricate a front main cap seal. I’ve not seen this in other brands. I’ll try to post a picture to show it. I have no idea how to use it.

[Wild Jimmy]

https://p15-d24.com/topic/55364-o-ring-for-oil-pan-gasket/#comment-593626

 

Read this post by dodgeb4ya

[Doug&Deb]

I remember now. They go under the diecast piece that the front seals on. 

[Matt Wilson]

On 6/7/2023 at 8:05 AM, Sniper said:

 

Excellent question.  Not so long ago I was under my 51 working on the steering.  For some reason, probably boredom, I decided to put a wrench on the oil pan bolts, they were all loose.  Might be a good idea to add retorquing to the oil change procedure.  Loctite wouldn't hurt either.

I'm thinking I'll add the use of some light-duty thread locker to my engine assembly checklist, for the oil pan bolts.  Maybe the timing cover bolts too.

[Bob Riding]

Update on my oil pan flattening efforts: I was successful in flattening the oil pan flanges (didn't take much force), then I used Gasgacinch on the pan side and bearing grease on the engine side. I "borrowed" some push pins from my wife's stash, and cut them in half, then pushed them through the gasket ends. I did trim the 2 end gaskets to 1/8" above the surface, as the Gaskets were over 1/2" proud on each side, which seemed too much.  Easy-peasy. I then dipped the pan bolts in Locktite Red (the weakest of the brand, apparently), then torqued the to 15 ft lbs. We'll see if I get any leaks.

[FarmerJon]

Glad you got your new pan on, hopefully it will be the end to your leak!

I wouldn't stress about it, but not sure who told you that Loctite Red is the weakest. 

If you did not degrease the holes they will come out without heat.

Blue 243 is the industry go-to for fasteners that will need to be removed down the road.

[Bob Riding]

11 minutes ago, FarmerJon said:

Glad you got your new pan on, hopefully it will be the end to your leak!

I wouldn't stress about it, but not sure who told you that Loctite Red is the weakest. 

If you did not degrease the holes they will come out without heat.

Blue 243 is the industry go-to for fasteners that will need to be removed down the road.

My mistake- they are all red on the outside! Actually I used the 222 (Low Strength) which is purple. Thanks for the clarification.

[FarmerJon]

Glad to hear! Loctite is good stuff, but red can be a hassle to remove.