How NOT to install crankshaft seals! - PeachParts Mercedes-Benz Forum

ROLLGUY · #1 08-26-2022, 10:36 PM

I am working on a friends car, removing the engine to paint the engine bay. We are also replacing the head gasket. Since the engine has been leaking profusely from the rear crankshaft seal since the purchase of the car (the engine was supposedly "rebuilt"), I decided to go all the way and replace the front and rear crankshaft seals. The front seal was installed improperly- not tight against the block. Just when I thought I'd seen it all, I was proved wrong! The "rebuilder" did not install the rope seal properly, but installed it in one piece with the gap on the bottom! There was a glob of silicone in the gap as well.

vstech · #2 08-29-2022, 11:47 PM

Wow…
I mean, it is such a simple job… needs a razor blade, and a rolling pin, or patience with he crank… but hard to imagine a shop would do that…

280EZRider · #3 08-30-2022, 12:47 AM

Unbelievable! You better go over the entire car, just in case this moron touched anything else. Thanks for sharing the buffoonery, it's really good for a giggle.

ROLLGUY · #4 08-30-2022, 01:01 AM

Quote:

Originally Posted by 280EZRider

Unbelievable! You better go over the entire car, just in case this moron touched anything else. Thanks for sharing the buffoonery, it's really good for a giggle.

Yes, the owner has found many other bad fixes before bringing the car to me. It was brought to me for a head gasket replacement and engine bay painting. We decided to pull the engine and completely reseal it. That is when I found the front and rear crankshaft seals installed wrong. The reason for the head gasket change is that the block had white streaks below the head gasket surface. All the head bolts were rusty, which suggests that the threads were NOT oiled (yet another rookie mistake). That could cause not enough clamping force from the bolts, and lead to premature head gasket failure.

ROLLGUY · #5 08-30-2022, 01:04 AM

Quote:

Originally Posted by vstech

Wow…
I mean, it is such a simple job… needs a razor blade, and a rolling pin, or patience with he crank… but hard to imagine a shop would do that…

I believe the previous owner did the work. He bragged about "rebuilding" the engine himself. The entire engine was painted Chevy Orange. It looked hideous, so it is getting painted satin black.

EDIT: Oh, and he used silicone for the pan to block sealant, and NOT the proper anaerobic sealant!

Shern · #6 08-30-2022, 02:53 PM

Quote:

Originally Posted by ROLLGUY

I am working on a friends car, removing the engine to paint the engine bay. We are also replacing the head gasket. Since the engine has been leaking profusely from the rear crankshaft seal since the purchase of the car (the engine was supposedly "rebuilt"), I decided to go all the way and replace the front and rear crankshaft seals. The front seal was installed improperly- not tight against the block. Just when I thought I'd seen it all, I was proved wrong! The "rebuilder" did not install the rope seal properly, but installed it in one piece with the gap on the bottom! There was a glob of silicone in the gap as well.

Woof... these photos are painful.

Reminds me of the number of w123s in the yard I find with a spool of wire bridging fuse terminals.

87tdwagen · #7 08-30-2022, 04:17 PM

Wow, I wonder if the four most commonly used tools in the PO's tool box are a sledge, duct tape, a silicone caulk gun, and a 2x4...

Thanks for saving that engine!

Junkman · #8 08-30-2022, 09:51 PM

Quote:

Originally Posted by vstech

Wow…
I mean, it is such a simple job… needs a razor blade, and a rolling pin, or patience with he crank… but hard to imagine a shop would do that…

I've seen some pretty poor work from shops. I had one replace a clutch, rear main and seal the transfer case on my 00 Cummins because I didn't want to do the job in the gravel. I supplied quality clutch (South Bend) and a Cummins rear main with the proper installer and FSM pages.

The rear main leaked horribly and the transfer case didn't go 500 miles before it started leaking again.

I've figured out how to correct the issue of poor shop service. I built a 30 x 40 shop and installed an Atlas 12 ton 2 post lift. Now I don't have an excuse and will put my best man on the jobs (me).

BillGrissom · #9 08-31-2022, 06:59 PM

The rear seal is challenging on the OM617.952 since you can't just push a new graphite rope seal thru the gap like on an old Chevy. Instead, it has protruding rods which secure the rope from spinning (good idea), but requires dropping the crankshaft a bit to replace it (pain). I recall an older post from OP Rollguy where he did that on another engine, dropping the crankshaft down just enough to work the old rope out.

If going thru the trouble of rebuilding an engine, best to research and get the proper materials. Using silicone to seal the upper oil pan isn't right. Not the only engine like that. The GM Northstar had a somewhat similar split-block, and the factory seal there proved problematic (better method today). Many people are like this owner. My departed dad (bless his heart), would spend a day taking something apart, then use some hokey method like duct tape to "fix it" rather than getting the correct parts and tools, would fail and he would decide "nobody can fix anything, so don't try". People who think owners in the 1960's knew about cars are mistaken. Most didn't even open the hood to check oil since service stations did that. Today we have the internet, so no excuses and no need to believe advice from crazy uncles.

vwnate1 · #10 08-31-2022, 09:18 PM

Well ;

At least he had the good sense to bring it to you for proper diagnosis and repair Rich .

I see quite a few oil / grease seals that are banged in with a ball peen hammer, denting them beyond any use .

My 240D's head gasket weeps as you describe, I can't lift that heavy cast iron head off..........

jake12tech · #11 08-31-2022, 10:49 PM

Wow what a schmuck. Who does that? I’ve never seen that before and I’ve seen some rig jobs. Glad you’re doing her right.

vwnate1 · #12 09-01-2022, 08:06 PM

Whom ? .

Plenty as it turns out .

Something like 90 + % of all the works I've done over the decades have included fixing others mistakes or deliberate damage .