Front Crankshaft Seal Leak

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dblift
Posts: 3
Joined: Tue Jun 23, 2015 3:54 pm

Front Crankshaft Seal Leak

Post by dblift »

Hi Everyone,

So I come out of the coffee shop, hop in the Pinz and start it up. I immediately notice a new and unfamiliar rattle from the engine, which speeds up and slows down with the engine RPM. I take the small engine cover off and notice an unanticipated liquid that has been sprayed around the front of the engine. Is the engine too hot for the undercoating I had applied a couple of weeks ago? Nope, that's motor oil, presumably being flung around by the pulley for the fan belt. Being clueless about where the leak could be, I nervously drive the one mile home. The following day, I remove the engine cover to take a look. It's so obvious even I can figure it out; the seal behind the pulley (part 01-05-04 in the diagram book) on the front of the crankshaft is bulging out and can be moved fairly easily with my hand. It might be the original one, it feels like bakelite and my thumbnail can take a chunk out of it.
Image
Image

Now the questions:
1. Is this a common failure, or one that should be considered not too unusual due to possible age of the part, or should I suspect that another interior mechanical failure pushed the seal out? I.e., should I be thinking about pulling/dismantling the engine, which I do not have equipment to do, or should I just order 4 or 5 of these things?
2. The manual describes pushing the replacement seal in with a 'pressing sleeve.' Seriously!? That doesn't seem real secure to me. Should I anticipate that some kind of ring-shaped potrusion on the inside of the hole will break off and fall in the engine, once again necessitating engine removal/disassembly?
3. The parts cross-reference that several sites display (here's an example: http://madscientisthut.com/sdp-pin/html ... rence.html) shows an equivalent Chicago Rawhide #19655 part that I could use. Does anyone have any experience with this part that would suggest it is any better than the one I could get from SAV?

Since it seems like a common question, I'm in Calgary, Alberta.

Have a good day, and thanks for the help.
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rmel
United States of America
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Location: Woodside, CA
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Re: Front Crankshaft Seal Leak

Post by rmel »

It's a $10 part, if that's all you need. http://www.pinzgauer.com/showdetails.ph ... o=9023834/
Looking at maintenance doc's you may be able to remove/replace this seal by removing the pulley. Looks well beyond
any "Stop leak" additives :(
Puller: 71' 710K 2.7L EFI aka Mozo
Follower: Sankey MK 3, 3/4 Tonne
Rescue Pinz: 73' 712MK

Driver: Ron // KO0Q
dblift
Posts: 3
Joined: Tue Jun 23, 2015 3:54 pm

Re: Front Crankshaft Seal Leak

Post by dblift »

So I finally get around to replacing that seal. Since I didn't want to wait for the proper pulling tool for the pulley, I improvised with a harmonic balancer pulling tool from Auto Value with some longer bolts and washers from the parts bins. I pulled out the pulley, and to my chagrin found that a large piece of metal was missing from the base of the pulley. Since I fished around in the hole to find the missing piece and managed to knock it further into the engine, I got myself an inspection camera and bendy magnet probe. The inspection camera proved to be no use (so don't spend the $$), but the bendy magnet probe got the fragment out in less than a minute. Check this out (the circular spring in the upper corner was around the shaft, since it does not appear in the diagram, I assume it was part of the seal):
https://s32.postimg.org/jw8ci1blx/IMG_2108.jpg
The fragment I got doesn't appear to fit very well, so I use the bendy magnet probe to fish for the fragments:
https://s32.postimg.org/p3kxo6v5x/IMG_2110.jpg
And oh-ho, what do I find? It would appear a previous owner had the same issue. Another fragment, obviously from an identical part:
https://s32.postimg.org/9rqjqubgl/IMG_2109.jpg
The second fragment I pulled out proved to be the one from the current pulley. It's just like in Cinderella:
https://s32.postimg.org/9rk0w23rp/IMG_2111.jpg
Bendy Magnet Probe, a fine addition to the team:
https://s32.postimg.org/pisktc9o5/IMG_2114.jpg
I don't really need links for parts to order, I know how to find parts.
Has anyone else had this problem, which seems to be recurring in my case?
Is there a potential source of this problem that I don't know about?
Am I maybe driving wrong? I drive around town, two or three times a year I go out of town. When I go out of town, I keep it a little over 50 mph, and stay on non-highway roads to avoid traffic when I can, although my destinations are usually one or two days drive away.
Any advice would be appreciated.
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Jimm391730
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Location: Idyllwild, CA

Re: Front Crankshaft Seal Leak

Post by Jimm391730 »

I've had the pulley off several times, both during engine rebuilding/EFI installation as well as to replace the seal - no problems like you show have occurred. Since it's apparently happened twice, I'd suggest that there is something with your engine that is causing the problem. First thing I'd check is to look for any burrs or any deformation on the crank shaft that could be stretching the cast pulley and causing the (repeated) fracture; also check for the correct key size - if it is too big the same thing could happen. The pulley should relatively gently slide on and off; the bolt just holds it in place. If the pulley is tight, you've probably found the problem.
Jim M.
712W and 710M
dblift
Posts: 3
Joined: Tue Jun 23, 2015 3:54 pm

Re: Front Crankshaft Seal Leak

Post by dblift »

Thanks Jim,

I will try to slip it on first and see how smooth it is.
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