When I was looking under my truck today I saw something on the ground under the engine, I tasted it and sure enough, it was oil.

And it is leaking pretty badly, I noticed for the last few days I would see a small puddle under the rear of the engine.

I got under there tonight and tried to find out where it was coming from but I really cannot see.

I thought it might be from the breather tube but it is clear and it is not coming from the side cover or the valve covers as well as I can see.

It looks like it might be coming from the rear of the engine. If you lie on the ground and look up it looks like it is from between the front of the trans and the rear of the engine, and it is defiantly engine oil.

Other then the rear main is there and other place it could leak from? I was hoping it was the #6 valve cover but they are all dry.

What kind of seal is this, a one piece or is it in the main bearing?

If it is the rear main, what is involved in replacing it?
Can I replace it by pulling out the transmission?
Can I replace it without dropping the pan?

Why would cause this to start leaking? The breather is clear.

I know I am looking at a lot of if’s at this point until I get under there with the engine running and a good light but here is where I need some help.

Does anyone have a breakdown for this engine or at least the rear of the engine with some decent pictures of what is back there and some part numbers.

Is someone could scan a few pages from the FSM it would be very much appreciated, My local Dodge Dealer just got new computers and they haven’t figured out how to make them print yet.

Of course it couldn't happen in the summer when I could work on it at 3:00 A.M. without this dang cold 60* weather we are having.

Let me know if you have any other ideas.
Thanks for the help.

Jim

 

Jim, all I can tell you is that the rear main can be replaced without droping the pan, but you do have to pull the tranny. I beleive it is a one piece but am not 100% on that.

 

The rear main is one piece and can be replaced without dropping the oil pan but the transmission does have to be removed. The adapter plate between the block and the bell housing also has to be removed. Not too big of a deal though.

Another place it could be leaking from is the rear cam plug. Its basically a steel freeze plug that caps the end of the cam bore in the block. Its easy to replace except for the fact that to replace this you have to remove the transmission and the adapter plate also.

So once you've got everything taken apart this far you might as well replace this plug and the rear main seal.

 

I have a set of manuals for the B series engine, it came with a CD too. Does anyone know how the get pics out of a .PDF file. I cannot do it on my computer, do you have to buy the full version of acrobat? I would be glad to share any or all of the info. It says its like 138MB for both books.

I don't want to argue, but I don't see why you would have to remove the bellhousing adapter to change the rear-main.

 

I guess you probably don't have to remove the adapter to change the rear main, but to check the cam plug you do. And I personally know of 2 trucks that were leaking from the plug and not the rear main.

 

You don't HAVE to remove adapter but it's lots easier to get the old seal out, the crank cleaned, and the new seal set to the correct depth w/o the adapter in the way. W/ the adapter still on, you're constantly working in a hole.

 

Jim, as long as you have things apart, you might look at the condition of your flexplate and upgrade it and/or the torque converter if you haven't already.

On the slim chance that you have a groove worn in your crank (mine didn't have a groove and I had 245K last time I had it apart), you can buy a sleeve for the crank BUT, the rear main seal with the sleeve is different than the rear main w/o the sleeve due to sleeve thickness. Make sure that you put the new seal in bone dry or it will leak in the future.

Lots of good reading out here on replacing the rear main if you do a search on it.

 

It was nice and hot yesterday and now it decides to rain so I won't be able to check it out right now, I will try it later.

If I pull the trans is everything accessible from the rear of the engine and about how much does the A727 transmission weigh?

I had the transmission rebuilt about a year ago and I got a new torque converter then so I am hoping that part is fine.

What is the story on the upgraded flex plate?

How much of a grove would be acceptable? Couldn’t you set the seal at a different depth?

Are there any special tools need for this repair?

When it Leaks, it Rains

Thanks
Jim

 

Have you actually seen it DRIP ??

You got this real nice shiny new truck.

It has got to make those that are less fortunate envious and jealous.


It is possible that some prankster has been making an oil puddle to mess with your mind.


For your sake, I sure hope so.

 

If you can catch your fingernail in it, it's too big a groove. There's a special tool for installing the seal/sleeve combo if you need to go that route.

If the cam plug is not leaking, don't mess with it.

 

Dave,
Where would the best place be to get the seal, Dealer, Cummins or the Auto Parts?
Also does the special tool come with the sleeve kit?
Jim

 

Unfortunately did see the drips,

I am gong to repair the leak before I take it into the body shop; they still need to install the side molding and buff out all of the paint yet.

It is possible that some prankster has been making an oil puddle to mess with your mind.

I actually did do that to a guy I worked with back in the early 70’s.
This guy was completely **** his name was “Julius” and had a perfect 1966 Buick Rivera and kept messing with me so every day before lunch I would sneak out into the parking lot and pour a small puddle of oil under his car, a different place under the frame each day. I must have driven him nuts; he kept taking it to the mechanic. But they could not find out where it was coming from.

Man I hope it is not Karma getting me back.

There should be a statute of limitations on Karma isn’t there?

Jim

 

Try to make sure its the rear main before you go in there. Could be the pan gasket.

It is amazing how many leaks I have. I have fixed my front gear box cover leak, front main seal, and oil pan leaks, but i still have to fix the vacuum pump and rear main seal leaks.

 

When I was looking up from the bottom I saw there is a bit of a gap in the bottom, do you think I could get a borescope in there to see the seal?

If I pull the starter is there anything to see looking through the hole?

I am going to clean it off and get under there when the engine is running and see if I can find where it is coming from, the rain should be gone by this afternoon.

Thanks Jim

 

I chose to go to Cummins.

On my '92, the part # as per my Cummins receipt was 4089342 and it cost me $41.14 plus tax. That is the seal if you DON'T need the sleeve and it did come with the seal installation tool. No other special tools were needed.

Part #3926126 is the seal and sleeve kit and it does require an installation tool to press the sleeve onto the crank and that tool is not included. The cost on that seal/sleeve kit was $79.46 at Cummins.

There also is a rear cover gasket that you will need if you choose to remove the rear cover (not recommended unless it's the cause of the leak). It it part # 3938159 and cost $6.42 at Cummins. Be aware that if you remove the rear cover, you will have to reseal the oil pan in that area, thus the recommendation not to remove it.

Hope that this helps.