Camshaft oil seal leak

[jaymanek]

Just to update, both cars eventually started passing small amounts of oil again in one or both caps... leaving me embarrassingly stranded in petrol stations and car parks. The worst is outside kids school in a busy car park and my car starts to pop and bang.....

Luckily i am now carrying around 5mm allen keys and brake cleaner cans!

So i bought the front covers, seals etc etc and did it "properly".

So what have i learnt?

I think the issue with replacing without removing front covers is, that no matter how good your tool, you cannot clean up the end of the camshaft properly.
I found that when the end of the camshaft is in front of you, the issue is obvious. A relatively thick layer of dry corrosion will make it difficult for any rotating rubber seal to effectively do its job.

I guess this may not be such a problem in some climates but condensation within an engine is going to be pretty normal so i would have thought it would be a universal issue.

When installing the seal with a new front cover (pre pressed into the cover), with the camshafts cleaned up, the seal glides on effortlessly.

Now i will need to test both cars but i feel much more confident that this issue is behind me now.

Also its a more satisfying job, new sealant on the cam magnets, new rocker cover seals etc.

Ps i have worked on M119 for years... i dont remember the back corner rocker cover bolts being such a PITA!!

I used new front covers just because I didnt want to do this job for the umpteenth time.

Thanks

 

[gsxr]

Jay, do you have new cam magnets as well? Or, re-sealed magnets as shown in this thread?

 

[jaymanek]

Hi, No i didnt take them apart to that extent. i only resealed them back onto the front cover using Mercedes sealant.
There was no leaks from them before.

 

[emerydc8]

Ps i have worked on M119 for years... i dont remember the back corner rocker cover bolts being such a PITA!!

I used new front covers just because I didnt want to do this job for the umpteenth time.

Thanks

The condition of the motor mounts affects accessibility to the rear valve cover bolts. I don’t remember which is more difficult—new mounts or worn mounts, but I do remember there was a difference.

 

[gsxr]

Hi, No i didnt take them apart to that extent. i only resealed them back onto the front cover using Mercedes sealant.
There was no leaks from them before.

OK... if they are original (104- part number prefix), keep an eye on them over time. These can leak oil from the seam between the metal sandwich as shown in that other thread. If you have the newer 119- prefix magnets, those may be fine.

 

[handyandy46]

I recently noticed that the front crankshaft seal comes from the factory partially set inward, by approx 1.5mm. I've found this on several different motors which appear to have original seals, so I'm assuming this was the factory installation position. The problem is, when installing a new seal, the tool will only set the seal either flush, or inset 3mm. That means the new seal will be ±1.5mm from the old seal, which I don't think is quite adequate to move the new seal to a completely fresh area on the hub. For the last seal I did, I installed it ~3mm out from factory, which is ~1.5mm out from flush. It's not easy to do this as the tools weren't designed for it. So far, this has worked well, it's 100% dry. I plan to do the same on the next one too.

How do you measure this depth? Might be a dumb question but I figure I'd ask, lol

 

[gsxr]

How do you measure this depth? Might be a dumb question but I figure I'd ask, lol

After removing the balancer & hub, you get creative with a straightedge and feeler gauges.

Also read this entire thread for the front crank seal:

M119 front main crank / hub seal replacement | M119 Engine

My front main crankshaft seal is leaking and needs replacement. I've looked through the service manual and Mercedes calls for installing a special locking tool to prevent the engine from rotating while undoing the main bolt and later retorquing it to the required 400Nm. I looked for info from...

www.500eboard.co

 

[Alphasud40]

Very good point Dave. It’s okay to shift the position of the installed depth whenever possible change the wear point on the pulley. Otherwise you might end up with the same leak as before or the new seal will not last as long as the original.

 

[400Benz]

Whoops, just installed this awhile back and didn’t see this thread i suppose this time i can do it the right way.

 

[nocfn]

that is a Jed Clampitt Gusher!