Replacing rear main - what else while in the 'insanity ward'? (1 Viewer)

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Question for you all - possibly have a common rear main seal leak (some pics below), and if this is the case - what else should I be considering to replace while there for replacement?

Some pics of what I am looking at:

I know I also have a front leak where timing cover is as well as oil pan leak, but the rear main is a mystery for me - any yet it may be just the oil pan leak that looks like the rear main (will remove shields later). With the oil pan gasket replacement, replacing the oil pump may be a good option while there....most of this rig is 100% original - almost like a time capsule.

Thanks for any advice.
 
Pull the inspection cover and see what the back of the block looks like. You're looking for radial oil spray if you have a RMS leak. That's a pretty mild film, relatively, so it could be coming from lots of places.
 
Pull the inspection cover and see what the back of the block looks like. You're looking for radial oil spray if you have a RMS leak. That's a pretty mild film, relatively, so it could be coming from lots of places.
Will do just that. Meaning Radial spray within the main bell-housing/shroud (not sure that is the technical name), correct?
 
Correct. RMS failure makes a mess behind the flywheel.
 
While doing the oil pan seal and if the trans is off, I replace the rear main seal, pilot bearing, trans input shaft cover gasket and seal. Then inspect the expansion/core plugs on the rear of the block once you have the bellhousing off.

Also look at the flywheel and resurface if hot spots or cracks - then I'd usually do a new clutch if its old or oily or unknown condition.
 
I went down this path over the winter. Mine was leaking oil from a lot of places so I did the timing cover seal and gasket, the pushrod gallery cover gasket, replaced both the oil pan and gasket, RMS, had my flywheel resurfaced, and installed an Aisin clutch kit. While the transmission and transfer case were out, I resealed both cases (they were leaking too) and replaced the o-rings in the speedo housing (included in the reseal kit for the t-case).

For reference, a photo of my flywheel with obvious RMS leak. The seal was so loose it came out with the flywheel.
1D329EC0-BE78-45B8-85A1-F3722429A64C.jpeg
 
Nice of the RMS to save you the removal step!
 
I would clean everything on the motor, trans, and xfer case to bone dry before deciding what to tackle.

I had a drip from the front rounded oil pan gasket and dreaded a replacement. I cleaned it all up and determined two or three side cover screws were a little loose. Tightened them up, no more leaks!
 
While I never experienced it hear the plug at the back of the cam shaft can leak as well. Since that not a seal you expect to wear would take the approach if it isn't broke to fix it. Replace the plug as preventive risk the new plug didn't get seated properly and created a leak.
 
I would clean everything on the motor, trans, and xfer case to bone dry before deciding what to tackle.

I had a drip from the front rounded oil pan gasket and dreaded a replacement. I cleaned it all up and determined two or three side cover screws were a little loose. Tightened them up, no more leaks!
That is what I am going to do. @73FJ40 have you ever used any UV dye to spot where a leak may be originating from?
 
Well found some interesting results here after removing the access hatch as well as the OEM rock guard. @Zjohnsonua thoughts?


It appears that the main is fine, but not 100% sure. Take a look at bell housing pics and transfer case:

Bell Housing Pics/Flywheel

IMG_4975.JPG


IMG_4978.JPG



IMG_4977.JPG


(the orange silicone is a mess and looks sloppy/bad seal at back of oil pan)

Transfer Case Leak - bad transfer case F&R seal?

IMG_4983.JPG


IMG_4986.JPG


All pics from this morning can be found here (at bottom of G Photos page):
 
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That is what I am going to do. @73FJ40 have you ever used any UV dye to spot where a leak may be originating from?




I agree with your plan to clean everything up first. I'd check all of the fasteners for tightness (don't overdo it).

While I never experienced it hear the plug at the back of the cam shaft can leak as well. Since that not a seal you expect to wear would take the approach if it isn't broke to fix it. Replace the plug as preventive risk the new plug didn't get seated properly and created a leak.

@Living in the Past identified another potential leaker, but I believe it's difficult to replace with the engine in place. I think that the flywheel and bell housing need to be removed in order to find leaks on the back of the engine.
 
There may be a seal leak back there, but it isn't worth tearing the driveline apart at this time IMO. You appear to have a pan seal beginning to fail which you may be able to address by tightening the pan bolts a bit.

However, these cork gaskets aren't the greatest for longevity or consistency, which is why very few OEMs use them anymore. It's also why whoever was in it last time used RTV (a little heavy handed perhaps, but far from the worst I've seen). The pan, side cover and timing cover gaskets are bad about taking a set and weeping - exactly what you have here. Pan and side cover can reasonably be done with the engine in the truck. Timing cover can be more than some want to take on as the balancer has to come off.
 
There may be a seal leak back there, but it isn't worth tearing the driveline apart at this time IMO. You appear to have a pan seal beginning to fail which you may be able to address by tightening the pan bolts a bit.

However, these cork gaskets aren't the greatest for longevity or consistency, which is why very few OEMs use them anymore. It's also why whoever was in it last time used RTV (a little heavy handed perhaps, but far from the worst I've seen). The pan, side cover and timing cover gaskets are bad about taking a set and weeping - exactly what you have here. Pan and side cover can reasonably be done with the engine in the truck. Timing cover can be more than some want to take on as the balancer has to come off.
@Zjohnsonua thank you for this.....with that front timing cover (aka nightmare)....you take the rad off and anything in front of engine....then what else do you remove to get that main timing seal (not the top one, but the main one that is the important one) replaced? Does the fuel pump come out, distributor, water pump, etc....trying to get a sense of what else I can replace if I am taking coolant lines off (replace ALL of those) and other engine items - as I am not going to remove the engine.
 
Clean it up and have a look after a few miles, may be more than 1 on the t-case, that said it doesn't look bad, just dirty and probably the outputshaft seal behind the rear output yoke/flange. Not sure if you can just remove flange & d-line and replace that seal on a split case, that'd be a call to Georg/ Valley Hybrids - Cruiser Brothers, and he can sell you the new seal as well. The split cases are not typically leakers.
 
X2 on cleaning everything first
I would do the easy stuff first before a large project
valve cover and pushrod cover can both be leaky and appear to be coming from elsewhere.
looks like the oil pan was done in the past
 
….well go figure, entire left side of oil pan, bolts were loose. I torqued them all to 7 ft lbs (really low) and spiral pattern. Maybe we will see less leaking from this but still will replace the oil pan gasket as the orange stuff looks bad and someone with no skills.
 
Well @peesalot and @Zjohnsonua I found one small leak that I was looking for....and here it is. Can you tell if this is a bad worm shaft seal on the steering box (is this common)? It is completely dry above the box itself, meaning no ATF from the lines into the box or anything else leaking down on to the box itself that I can find. Very small drips.

The liquid is like thin brown solution - almost rusty liquid....not like the red ATF (distinctive smell) I am using for the PS hydraulics. Not sure if this is some kind of other oil from the box? BTW - This box was rebuilt by JT Outfitters (read between the lines here), so safe to assume the rebuild was a fail from them. I know its hard to find a good steering box rebuilder.

I am over my PS woes at this point....just want this dry and correct.



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Just an observation, a rebuilt box should not have rusted dirty splines, I would replace the entire box, call Kurt ,cruiseroutfitters. Or, try switching to the Royal Purple synthetic power steering fluid.
 

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