W123 300d Oil Leak...... - Page 4 - PeachParts Mercedes-Benz Forum

Alec300SD · #46 04-06-2017, 11:46 AM

Quote:

Originally Posted by MongooseGA

Any luck with this?

I went to do this job tonight but had a hell of a time getting the turbo mounted section free from under the turbo. Tried twisting and turning trying my best Tetris but no dice. It will not clear the lower pipe and come out the bottom. Any thoughts? I'm also not sure how to scrape the bottom flange of the old gasket without removing the turbo; this wasn't mentioned in the diys I've found.

This should be my last job of a long list to get this back back to daily status after a few week hiatus. I'm getting anxious!

You have to compress the lower tube further into the housing by pressing down on the upper tube (using a hard wood tapered dowel in place of a metal punch the the bolt hole of the upper tube will prevent marring the sealing surface).
See figure one...Drain punch down on this post: Turbo Drain and Blow-by Drain Seal Replacement; Mein Kampf
When the lower tube is further in the housing the upper tube will lift off when rotated to the right position.

Then you can scrape off the old gasket without removing the turbo.

Note: Trim the old leaking seal off the lower pipe before you compress it further into the housing.

I remember seeing the video years ago, IIRC installing the two tubes with the turbo in place should be according to the following procedure:
1) install the lower tube all the way into the housing with the two o-rings installed and the fat rubber seal in the middle of the tube
2) put the upper tube atop the lower tube and rotate the upper flange in place with it's gasket and tighten the bolts to the turbo oil feed flange
3) pull up the lower tube to seat it's upper o-ring into the bottom bell of the upper tube
4) pull the fat rubber seal down the lower tube to seat it on the lower housing.

I need to do this job on my 83 W126 300SD, but I'm planning on doing it when I changeover to non-EGR manifolds (the turbo has to come off the exhaust manifold for that job).

MongooseGA · #47 04-06-2017, 12:31 PM

Quote:

Originally Posted by ROLLGUY

The key is to completely remove the rubber grommet so the lower tube can move to the side. Sometimes a small piece will remain around the tube, and prevent it from moving enough to get the top tube out. Once the upper pipe is out, you can clearly see from below to clean (scrape) the gasket off the turbo.

Thanks! Will Try this out tonight. When you say remove the rubber grommet from the bottom of the lower tube, what's the trick to doing that? I do have a new tube, so I'm not terribly afraid of damaging the existing one during the process.

Quote:

Originally Posted by Alec300SD

You have to compress the lower tube further into the housing by pressing down on the upper tube (using a hard wood tapered dowel in place of a metal punch the the bolt hole of the upper tube will prevent marring the sealing surface).
See figure one...Drain punch down on this post: Turbo Drain and Blow-by Drain Seal Replacement; Mein Kampf
When the lower tube is further in the housing the upper tube will lift off when rotated to the right position.

Then you can scrape off the old gasket without removing the turbo.

Note: Trim the old leaking seal off the lower pipe before you compress it further into the housing.

I remember seeing the video years ago, IIRC installing the two tubes with the turbo in place should be according to the following procedure:
1) install the lower tube all the way into the housing with the two o-rings installed and the fat rubber seal in the middle of the tube
2) put the upper tube atop the lower tube and rotate the upper flange in place with it's gasket and tighten the bolts to the turbo oil feed flange
3) pull up the lower tube to seat it's upper o-ring into the bottom bell of the upper tube
4) pull the fat rubber seal down the lower tube to seat it on the lower housing.

I need to do this job on my 83 W126 300SD, but I'm planning on doing it when I changeover to non-EGR manifolds (the turbo has to come off the exhaust manifold for that job).

So use the upper tube to jam the lower tube down into the pan. Got it. Would this not represent a risk of bending the upper tube? Or should there be enough play that the lower tube drops in pretty easily?

I've been trying to get this done without removing the lower pan, but it's looking like that may be my best option for getting the lower tube back out of the lower pan.

Alec300SD · #48 04-06-2017, 02:14 PM

Quote:

Originally Posted by MongooseGA

Thanks! Will Try this out tonight. When you say remove the rubber grommet from the bottom of the lower tube, what's the trick to doing that? I do have a new tube, so I'm not terribly afraid of damaging the existing one during the process.

So use the upper tube to jam the lower tube down into the pan. Got it. Would this not represent a risk of bending the upper tube? Or should there be enough play that the lower tube drops in pretty easily?

I've been trying to get this done without removing the lower pan, but it's looking like that may be my best option for getting the lower tube back out of the lower pan.

First question: Score the hardened rubber grommet vertically in about four equally spaced locations.
Grab one of the rubber flaps you created with a good gripping pair of pliers (cross-hatched jaws) and firmly yank it upwards.

A piece will tear off, then go in with a sharp pen knife and score the newly exposed rubber under the lip of the housing.
Avoid cutting the housing itself with the blade.

Pull the flap opposite the one you've exposed and again score the exposed rubber under the lip of the housing.
You should now have a flap, a gap, a flap, and a gap on the old grommet.

Grasp one of the remaining flaps with your pliers and you should be able to yank out the old grommet.

Second and third questions: If you remove the large old rubber grommet first, there should be little risk of bending the upper tube.
The lower tube will be easier to move downwards with the old grommet removed and the upper tube is pretty stout.

With the fat grommet removed, you may not need to drop the oil pan, as only the lower o-ring will be keeping the lower tube in the housing.

MongooseGA · #49 04-06-2017, 02:29 PM

Thanks, Alec. I'm anxious to get home and get this job done. I love my 350SDL but miss the little 300D to scoot around in traffic with.

MongooseGA · #50 04-07-2017, 02:48 PM

I got the job done last night! It was a massive PITA and despite the helpful suggestions, the lower tube just would not cooperate with me.

Solution? Easy. I had a brand new lower tube on my work bench, and beat the snot out of the old one with a hammer and chisel to get it free from the upper. Cut the sonuva***** right in half. Not conventional, and I did need to be very cautious of the air cleaner return line, but it's done. Then to install I slipped the big grommet on to the lower tube, then both orings top and bottom. I stuck lower tube into upper pan and used a combo of socket extensions to beat it down as far as I could into the upper pan (lower removed at this point). Installed upper tube and hit the lower from beneath until it snugly clicked into the upper.

Ta-daaa! I don't want to ever deal with that again.

unkl300d · #51 06-29-2017, 10:49 PM

Quote:

Originally Posted by Shawnb

Against my own better judgement, I torqued the nuts down to 15ft lbs when hot this AM.....

No more valve cover leak as of this moment..

Drivers door wouldn't close on the way to work, luckily grease solved that. Going to pick up new strickers.

ShawnB did the torque down at 15 ft lbs continue to stop the leaky valve cover gasket?

Question for Other members: The spec is 15 Nm or 11.25 ft lbs. for the VC. 300D.
Wouldn't 15 ft lbs be excessive? I have read that torquing it down over the spec only causes more leaks and may mess the nuts/threads....

I am curious because my Victor Reinze VC gasket began to leak 7 months and 3K miles after the valves were adjusted by a mechanic (new Victor Reinz gasket back then and no leaks). I reset the nuts and torqued to 15Nm-cold engine- but it still has a bit of a leak. Next step is RTV unless it makes sense to tighten over the spec....thanks

ROLLGUY · #52 06-30-2017, 12:10 AM

Quote:

Originally Posted by unkl300d

ShawnB did the torque down at 15 ft lbs continue to stop the leaky valve cover gasket?

Question for Other members: The spec is 15 Nm or 11.25 ft lbs. for the VC. 300D.
Wouldn't 15 ft lbs be excessive? I have read that torquing it down over the spec only causes more leaks and may mess the nuts/threads....

I am curious because my Victor Reinze VC gasket began to leak 7 months and 3K miles after the valves were adjusted by a mechanic (new Victor Reinz gasket back then and no leaks). I reset the nuts and torqued to 15Nm-cold engine- but it still has a bit of a leak. Next step is RTV unless it makes sense to tighten over the spec....thanks

The shoulders on the studs keep the seal from crushing more than it should. A little bit more torque is not the worst thing. Too much torque will ruin the valve cover. Also, a washer against the aluminum helps save the cover. I have seen very few with washers.

BillGrissom · #53 06-30-2017, 01:18 AM

Agree w/ post 44 & 45. Removing and installing the turbo drain is a tetris puzzle, as is trying to access the 2 bolts up into the turbo, then orient the drain just right to slide it out. The old rubber bushing is usually hard, so you must pick it out in pieces until you can free the lower tube. Best to remove the lower oil pan, and that sometimes gives new surprises (found oil pump bolt unscrewed and plastic tensioner broken). With pan off, you can knock the remains of the old rubber bushing out the top and clean well, plus leave no broken bits in the pan. The new rubber will be soft and make reassembly possible.

Re valve cover gasket, it seems an incredibly bad design, trying to seal on a metal "knife edge", especially compared to most modern engines which use a silicone gasket trapped in groove and wide flat metal surfaces which bottom out to assuredly deflect the silicone, similar to a "face O-ring" design. I have a few leaks, but apparently not due to the valve cover. One appears to be from the turbo compressor side. The oil fill caps are prone to let oil by, but that is obvious since on top of the valve cover.

unkl300d · #54 06-30-2017, 01:32 AM

Quote:

Originally Posted by ROLLGUY

The shoulders on the studs keep the seal from crushing more than it should. A little bit more torque is not the worst thing. Too much torque will ruin the valve cover. Also, a washer against the aluminum helps save the cover. I have seen very few with washers.

Thanks for that RollGuy !

I will try a bit more torque first before doing the thing up with RTV.
I think I will set the T wrench to 17NM/12.5 ft lbs. and maybe go to 18nm/13.27 ft lbs another day if it does not work...I do have spring washers under the nuts.

(spec for the 300d non turbo VC nut is 15Nm)

ROLLGUY · #55 06-30-2017, 10:42 AM

Also, it is most important that the seal and both the head and cover be free of oil. I prefer Gaskacinch over Silicone for this. It is nearly impossible to re-use a seal (gasket) that has oil in the groove, and keep it from leaking.

unkl300d · #56 06-30-2017, 09:10 PM

Question, where does one buy the G Bruss w123 VC gasket? Doing research I discovered that Victor Reinz is very suspect. That is what is leaking now and what I have for a swap... so I am holding off.

I also read that Elring no longer makes them.

Its difficult to discern whether the dealer supply is Reinz or?? Peachparts sells MB but I have doubts since nowadays authenticity is out the door....

If no good quality is available anymore, then that makes the case for RTV or other such sealant !

unkl300d · #57 07-01-2017, 09:45 PM

OK so I called a local dealer and they were out but another dealer had three in stock across the bay. I was going there today anyway so I phoned to set aside one MBZ VC gasket (cylinder head cover gasket 6170160180)

They had three and I was intent on buying two.
I inspected the one he handed me and I saw a snail trail 'impression' about an inch long on the external sealing surface at the edge of the 'U' shaped section. And another oval shaped impression (3 mm) on the 'U' next to that one.
I rejected it and asked to see the other two.
One other had the exact same 'impressions' at the same spots and only one of the three was fine. (Although now that I have it home I opened it and noticed a very shallow 'impression' on the sealing surface of the rear most-end 'U' . Fortunately so faintly shallow my finger nail does not pick up the 'impression'.
The other ones were deeper and I was not about to have that 'flaw' seep oil on me !

So, heads up on the Mercedes G Bruss gaskets. One needs to inspect, inspect, inspect before taking it away.
Otherwise use sealer with any gasket.
The name G Bruss and Merecedes Benz and part number appears on the face of the front of the gasket. Label states "Made in Ireland" and the stock is from November 2016.

I measured the G Bruss gasket as 0.395 inch tall with a channel depth of 0.166 inch
The channel width was slightly narrower than the Victor Reinz. So this may aid sealing. The G Bruss 'appears to be 0.003 inch wider at the external sealing surface. Not significant.

The Victor Reinz measures 0.393 inch tall and channel depth of 0.180 inch

The Reinz has a series of 'proud' small installation direction arrows on the inside wall of gasket.

The rubber seems to feel the same to my touch and the rubber 'tension' seems the same (subjective).
And the Reinz external sealing surface has no flaws ('impressions'). 100% smooth.

The impressions I observed were like footprints left by a hot branding.

So there ya go. I am keen on installing the OEM Benz gasket naked with no subsequent oil leaks. I have never had valve cover leaks and never used sealers.
My present leaky gasket is a Vic Reinz.

funola · #58 07-01-2017, 10:49 PM

This is what to try if you've tried everything else and the VC gasket still leaks:

1. de-grease the VC gasket u-groove and valve cover

2. lay small bead of RTV all around on the VC

3. install gasket on VC and place on a perfectly flat surface and press down slightly to make full contact with the RTV

4. Let cure 24 hours before insall on engine

Make the bead of RTV wide enough to make the thickness of the VC gasket increase by about 1/16". Letting it cure on a flat surface insure VC + gasket is flat even though the VC may not be perfectly flat

I have not tried this since my VC gasket does not leak. If you try it, please LMK how it works.

unkl300d · #59 07-01-2017, 11:05 PM

Hi funola, yep, I did alot of research on other threads and read your same tips in those threads. You are correct ! Good info for the archives ! Other big sticks had the same method while those who used dealer OEM gaskets installed naked with good results.

I expect the OEM gasket to work.

I will try to update but it may take a while because the currently installed Victor reinz gasket lasted 7 months before it began to leak.

I hope this OEM one does it right the first time for a long time...until the next valve adjustment in about 4 years !

THANKS !

unkl300d · #60 08-17-2017, 01:59 PM

OK here is the update Funola.

I got around to installing the new dealer gasket about 2 weeks ago. Monitoring it, so far it is very clean and no oil seepage.
I basically followed your instructions but used Diesel Giant's pictorial for the non turbo engine. I just turned the cover on its back with minimal throttle linkage disassembly and one end of an overflow line to disconnect. I previously allowed car to sit in garage overnight so that it is cold and oil runs off the cover internally. With cover flipped on its back I cleaned the sealing edges liberally with brake cleaner on rags. Used a piece of plywood to give far edge support while cover sat inside of fender/engine bay.

I decided to go ahead and enhance the dealer gasket with RTV because I have little time to go back and repeat in case of leaks.
RTV assures the seal. PERMATEX Ultra Black gasket maker.
I opened the nozzle to the smallest opening (about 1/16")
Ran a small bead inside the gasket channel. (the small nozzle opening creates a challenge squeezing the RTV tube after a while as tube gets thinner.-requires patience)
Installing the new gasket,I came across one final end that had to be carefully pulled up into place for a tight circumferential fit. Do it carefully so as not to cause the other edges to come undone.
With gasket on the cover, I used a wooden roller on a handle to carefully depress around the top of the sealing edge. (wall paper edge roller?)
I let it sit for about 15 minutes while I wiped (no brake cleaner) the engine head top flange of liquid oil, making sure to not completely remove light oil film. I cleaned around the sides of the engine block also to prevent possible grime slipping in. I used a large hemostat with a small pad of rag on the tip.
Then I used my finger to spread a light film of RTV onto the sealing surface of the gasket.

My car is a non-turbo.
The cover fit back over easily. If you raise it over the studs and aim right, it sets right down without tangling up on anything.
Do be careful to navigate the A/C hose that runs in front of the cover. I removed the old dry insulation from mine and it created more clearance (and prevented crud falling inside if accidentally bumped) and later insulated it with proper tape once cover was on. Turbos may be a bit more tricky..
Cross tightening, I literally finger tightened the nuts. Let sit 2 hours but periodically checked the finger tightness and tightened some nuts a bit cross tightening pattern. I also periodically tapped around the top edges of the cover with a rubber mallet to help set downward. As the gasket sets, it allows for more even finger tightness over time.
After about 2 hours I used the ratchet and went back to progressively tighten. First only a few turns each and built up to a final 2 finger tightness.
3 hours later I rechecked the 2 finger tightness and found some nuts gave for a bit more tightening to get to the 2 finger stage. Did this in 2 phases. Cross patterns always.
The final phase at that point was the 2 finger tight and snug stopping point.
(3 finger tight is just above 15Nm).
The next evening after over 12 hours, I rechecked the final snug tightness and they were all still in synch.
I let the car sit until the next day just to make sure all settles and cures.
So far its all good ! My retaining nuts used spring washers. Clean the nuts and washers of oil before reinstalling.

For those in a hurry, supposedly the dealer sells RTV that cures in 30 minutes.

Thanks to all.