Characteristics of RMS leak?
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Characteristics of RMS leak?
1st post here - I'm working on a friend's '95 Laredo w/5.2 engine, 155,000 miles.
I've got oil leaking at the interface between oil pan and sheet metal flywheel cover. If it were the rear main seal, would crank rotation cause oil to spray onto the side of the flywheel facing the seal? I've removed the bolts holding the cover, peeked inside, and don't see any oil, either on the flywheel or the flange that the flywheel connects to on the crankshaft, or on the crankshaft OD, just forward of the flange. Mind you, I'm having to peer into the narrow space created by tilting the flywheel cover, since the oil pan is still attached.
I checked up above, running my hands around the back edges of the valve covers, also around the oil sender (as much as I could get my hand in there). I also tried probing around the base of the oil sender with a thin wooden stick, didn't come up oily.
What's the likelihood of the oil pan gasket failing in the area where it "wraps" around the crankshaft? And I'm assuming the exhaust has to be unbolted at the two manifolds to remove the pan? Someone had been in there before me, as one of the flywheel cover bolts was loose, one missing, and the bolt that secures the starter was missing, the starter being held by the one stud and nut. Wondering if anyone has the dimensions of that starter bolt handy?
Paul
I've got oil leaking at the interface between oil pan and sheet metal flywheel cover. If it were the rear main seal, would crank rotation cause oil to spray onto the side of the flywheel facing the seal? I've removed the bolts holding the cover, peeked inside, and don't see any oil, either on the flywheel or the flange that the flywheel connects to on the crankshaft, or on the crankshaft OD, just forward of the flange. Mind you, I'm having to peer into the narrow space created by tilting the flywheel cover, since the oil pan is still attached.
I checked up above, running my hands around the back edges of the valve covers, also around the oil sender (as much as I could get my hand in there). I also tried probing around the base of the oil sender with a thin wooden stick, didn't come up oily.
What's the likelihood of the oil pan gasket failing in the area where it "wraps" around the crankshaft? And I'm assuming the exhaust has to be unbolted at the two manifolds to remove the pan? Someone had been in there before me, as one of the flywheel cover bolts was loose, one missing, and the bolt that secures the starter was missing, the starter being held by the one stud and nut. Wondering if anyone has the dimensions of that starter bolt handy?
Paul
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Year: 1995
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Engine: 4.0 with all of the noise and clatter
It will pool inside the bell housing and look like it's the RMS. Plus every time the oil filter is removed it will make a mess and mimic a RMS leak. How much oil do you see back there?
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Every two days or so, there's a puddle about 4 inches wide on the ground. It's collecting at the exterior of the bottom of the oil pan "scallop", where it goes around the crankshaft, and running down the outside of the flywheel cover.
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I finally returned the car to it's owner two days ago after replacing the rms and pan gasket. After a 60 mile drive, the leak persists. But now, there's no evidence of oil where the pan wraps around the rear of the crankshaft, just at the bottom of the bell housing, definitely biased towards the starter (passenger) side. Before pulling the pan, I spent a lot of time up top feeling around for leaks and used a UV dye as well. The corners of the valve covers, while not exactly dry, weren't wet enough to justify the magnitude of the leak. And I got my hand down on the oil sender, the body of which was dry. I did feel some oil on the block near where the oil sender screws in, but it just didn't seem like enough to cause the leak I was seeing. The UV didn't show anything on the sides of the bell housing.
I'm thinking that there may be two leaks, one of which I fixed, the other still up top. When the oil sender leaks, does it run straight down the back, or around the sides of the bell housing? Also, is the correct socket for the sender 1 1/16"?
I'm thinking that there may be two leaks, one of which I fixed, the other still up top. When the oil sender leaks, does it run straight down the back, or around the sides of the bell housing? Also, is the correct socket for the sender 1 1/16"?
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#12
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It seems to me if the cam plugs were leaking, you'd see oil inside the bellhousing. I'd suspect the tappet chamber cover under the intake manifold. On the older 383, this was just sheet metal and they did rust thru in extreme cases. It was part of the intake manifold gasket and not a separate piece. Now I'm going back to 1965.
Last edited by dave1123; 07-26-2014 at 11:39 AM.
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Year: 1995
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Engine: 4.0 with all of the noise and clatter
Not very common. I read the first post again and noticed you're working on a 5.2. You could have a leaking gasket at the bottom if the intake manifold, that is very common on a Mopar small block. It's probably time to replace the plenum plate gasket anyway. If you do remove the intake make sure to torque the intake bolts properly and don't exceed 12ftlbs.
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Thank you all for replying. I'm currently in waiting mode, as the Jeep and it's owner are about 60 miles from here. We may get to work on it this coming weekend. I've read about the plenum gasket - will a gasket set from the auto store do, or is the one from Hughes Engines pretty much necessary?