Rear Main Seal - Upper "dimple" ?

Any pics? I'd love to see what you're talking about since I desperately need to repair a rear main seal leak I also have.

Josh

Josh.........I'm gonna wait for another reply, but, looking at one of my older (very old) manual. It looks like they say to remove the pin if you are installing a split seal (which is what the newer ones are). And yes, on the bearing cap you can see a small drift pin dead center which should just punch back out....... I'm thinking the original style was a single "rope" style, and that small pressed in pin would stop any rotation. They say (da book) to loosen all the caps to 1/32", then just use a drift to get out the upper rear section. On new installation (as with the split types) make sure to offset each by 3/8"..........so basically put the new upper side in and "around" so it comes back down a bit. Also important to make sure the flexible lip faces inwards to the engine side. (I'll let you know).

Bob,

I am not aware of a "dimple" in the rear main seal groove anywhere, block or cap. There is a small pin in the rear main cap's seal groove that must be removed whenever a seal with a metal core is installed, or else the seal will "squash in the area of the pin.

There is no pin in the block's rear main seal groove, you can knock the old seal out partially with a punch & hammer, grab it with vise grips & pull it the rest of the way out. Clean everything really well & carefully push a new seal in, leave one end of the seal hanging out about 1/4". Do the same with the cap, leaving the seal hanging out 1/4" on the opposite side. This way the ends of the seals are not joined at the cap parting line, lessening the chance of a leak. RTV the ends of the seals & reinstall the cap. Rock & Roll!

Your friend on the PIBB, George

This is excellent info!!

After troubleshooting my cooling issues last weekend, I'm now motivated to tackle the next job. And this just became the candidate.

Hell, I also need to finally install that removable crossmember I bought two years ago! Looks like the time is now!

Josh

George.......... I just punched it out. It was at about the 1pm mark, if you had the rear main cap on its feet (so to speak). I also found (2) items mentioned in my older books that said to remove it if you replaced the seal with a 2-piece. (and yea like you said, off-set the seals so they are not even with the cap joint itself for a better overall seal). One nice thing to confirm is that these motors (at least this one) is all 4-bolt caps.

JK......... BTW..........if you do this, and do the X-Member at the same time (which actually you dont have a choice in because that has to be removed to get the pan down), remember to take weight off the rear to relieve the stress to your lower a-arms.

Im kinda looking forward to this last project (aka the 10qt pan), since I just finished the radiator/water pump upgrades.........

Bob

George........just read closer what you said...... you are correct its a pin. (I just said dimple).

quote:

Originally posted by kaamacat:

Im kinda looking forward to this last project (aka the 10qt pan), since I just finished the radiator/water pump upgrades.........

Bob

Bob, you're a least a weekend ahead of me! Finished the replacing all the hoses, radiator, and cooling pump last week.~

Now's the time for the rear main seal!!!

...Kaamacat! The 'Book' also says; that when that PIN is removed be sure to fill the remaining hole with RTV to prevent a possible rear seal leak. And when I installed My 10qt. Oil pan, It did NOT clear the Emergency Brake 'BellCrank' Mount; So I had to Saw it Off! In the near future I will have to 'ReEngineer' a New Mounting location. I have been driving without the E. Brake for awhile. Not a real inconvenience, just unsafe. Good-Luck with it!...

Marlin is right, rtv the hole where the pin was, I should have mentioned that.

Marlin, my Pantera didn't have an e-brake when I bought it, the previous owner had installed Wilwood brakes. Installing an e-brake was near the bottom on my mental list of projects. Now you've written you had to remove the e-brake crank to install your oil pan! Is that an Armando oil pan? I've got one of those too.

Bob & Josh, you guys impress me working under your cars like you are. I just can't do that any longer, the Arthritis is just too painful. So I plan to pull the engine & zf this winter to do some projects my self.

Well, I know at least 4 Pantera owners who stayed home this weekend! I spent Saturday with Dougo from the PIBB. We talked Pantera, and about life in general. He made some wonderful margaritas. We tried gettting his Pantera running, I think his Holley needs a power valve, it was spitting fuel in the air when he stopped cranking the motor. I met his lovely wife & children, they took me out for dinner, Snapper Jacks, the best fish tacos in Ventura county. I had a great time, thanks Doug.

take care you guys, George

This worked great for me

http://www.panteraplace.com/page137.htm

Mike

Thanks Mike, excellent info!

its probably been a while since I have expressed appreciation for your contribution to the Pantera community, for the enthusiasm & energy you put into your bodacious web site, just always know that I do appreciate it.

your friend on the PIBB, George

quote:

Originally posted by george pence:
Thanks Mike, excellent info!

its probably been a while since I have expressed appreciation for your contribution to the Pantera community, for the enthusiasm & energy you put into your bodacious web site, just always know that I do appreciate it.

your friend on the PIBB, George

Mike, include me in that company!

My black GT-5 conversion LOVES your technical section!!

Josh

good point on the pin to rtv. I had planned on that, being on the safe side. (George.......I have 3 words that make this easier for me). Four Post Lift.......

At least the upper came out super easy. I just loosened the mains 1/32" as suggested (using feeler guage on the 13/16" bolts first to make sure they were all equally lowered, then, loosened the 9/16" ones).

The upper looked fine, the previousl seal was also offset 3/8"-ish, which it should be, which is good.......... good news is the lower half was bad in the lower area.

BTW........for anyone doing this, it is VERY important to not only offset the seal halves to prevent leakage, but, face he "lip" inwards to the engine area. This is normal for any hydraulic type seal, as any pressure will feed into the open area of the "lip", what actually looks like a cut section in the seal itself.... and expand it to seal better.

George, My 10 Qt. Pan (actually holds 9 Quarts by the dipstick), is a MOROSO pan. I didn't just have to remove the E. Brake 'Crank', I had to saw-off the entire mounting plate from the chassis (used a 'Sawsall'). The clearance between the pan sump (cubic in shape) and the chassis, on the drivers' side, was barely 1/2"; it was a very tight fit but we got it in. Last, be advised that on this particular pan, the sump and 'drain plug', hang down Below the belly line of the chassis, by aprox. 1/2". NOT good for piece of mind when going over 'speed bumps' or avoiding debris in the middle of the roadway! Thank-You Mike! For the great info on the E. Brake! I will study it in depth!

Marlin, I had a friend with a lowered 3 series Bimmer once who scraped his oil pan all the time until one day he split it (it was cast aluminum). We removed it & had it beefed up by welding reasonably thick aluminum plate onto it. Afterwards he could scrape the road with confidence, knowing the bottom of his pan was reinforced with 1/4" thick 6061 T6 aluminum!

Perhaps you could fabricate a small aluminum skid plate between the frame rails, angled, that would protect the front of the pan and help it slide over an obstacle, "when" (not if) the day comes that you hit something.

your friend on the PIBB, George

BTW........ That rear main seal replacment went great. (altough have not put the pan up yet, thats tomorrow).

I loosened the 9/16" outer cap bolts so that I could fit a set of feeler gauges 1/32" between the bold head and cap. (that way when I loosen the larger 13/16" bolts the crank will drop only as low as I had loosened the smaller bolt heads to. (the 9/16" ones, outers).

Then loosened full al the outside 13/16" main cap bolts.

Took off the rear main, and with a small drift the upper seal just came out-and-around.

Putting in the new one, i did sand/lap the outer edge of the seal, just a VERY small amount to get it started up and over the crank top, leaving 3/8" exposed. WORKED LIKE A CHAMP!

(Nice to see a full 4-bolt setup on this engine, and looks like the previous rebuild had some balancing done, as I can see the pistons had some work done to them)