I did a valve job today on my 1980 300TD. The job went perfectly until I put the valve cover back on with the new gasket. No matter how hard I tried to tighten it, the oil woud just seep around the gasket. I tightened it more and more till the bolt snapped. How do I get the bolt out and replace it? Why would the new gasket leak like that. I don't understand the HARD plastic gasket and why Mercedes uses ONLY 4 bolts????

Maybe all the tightening buckled the cover. There are threads about extracting broken bolts. Its not a nice job.

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Grumpy Old Diesel Owners Club group

I no longer question authority, I annoy authority. More effect, less effort....

1967 230-6 auto parts car. rust bucket.
1980 300D now parts car 800k miles
1984 300D 500k miles
1987 250td 160k miles English import
2001 jeep turbo diesel 130k miles
1998 jeep tdi ~ followed me home. Needs a turbo.
1968 Ford F750 truck. 6-354 diesel conversion.
Other toys ~J.D.,Cat & GM ~ mainly earth moving

If you take the cover off you just may find a little bit of the bolt sticking out. Then you can use a pair of pliers to remove it.
If not there's a good chance the part broken off is loose in the head. Maybe see if you can work on it with a small screwdriver?

If all else fails you need to drill out the center of the bolt and use a screw extractor to remove it.

Danny

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1984 300SD Turbo Diesel 150,000 miles

OBK member #23

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I might have a little luck going for me then. The bolt snapped right beneath the cover so there is about an inch of bolt sticking up still. I didn't know if it just unscrews from the head? Where can I get a replacement?

I thought those were studs? I have not had my hood open in a while. Cannot remember.

Either way, using a pair of Good clean vise grips should be able to remove the old stud/bolt. Then any "good" hardware store (not Ace or Home Depot) should have a replacement. Or you could get it from the dealer. If you were in FL, I would say give "Daytona Bolt and Nut" a try. They have stores all over the state and usually have hard to find hardware. It might be only a $1 part at the dealer? You never know.

It sounds like the gasket may have been pinched in the groove or not all the way in the groove part of the way around.

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AJ

1985 300D (SOLD)

I just removed the cover and it is a stud and it is SOLID. One of the screws on the exhaust side came out of the block completely and is now attached to the valve cover....what the hell did I do!!!

Two suggestions: Soak that broken-off stud with PB or some other loosening liquid and leave it overnight, or even 24hrs. Then tap the stud a bit around it to break it loose a bit--not enough to bend or break it, just to vibrate it well. Then do the vice-grip extraction. You might want to put an ice cube on the bolt for a while before you start--or spray it with something that turns cold (the stuff used to clean electronics comes to mind, which squirts liquid when it's applied with the can horizontal rather than vertical). When you get it out, take the stud with you to the screw store and ensure you get metric threads. In my part of the world, the clerk may not know the difference and SAE threads will really screw it up.

Good luck!

jb

Don't let me take the thread off topic, but I feel obliged to put in a personal-experience warning of my own. I assume you're referring here to those "Canned air" blasters that are used for blowing dust out of keyboards and things.

As a person who has found plenty of uses for spraying those things upside down over the years.... DO NOT DO THIS ANYMORE.

Seriously.

Under any circumstances.

Ask me how I know.

Apparently, a few years ago, idiotic young people somewhere decided that it would be fun to "inhale" the stuff. I never have and never would try it, but apparently there's some "high" effect that made people start doing it. Of course, some of them over-did it and found out just how dangerous it was the hard way. As a result, all the companies that sell this stuff are now adding something called a "bitterant". It makes the stuff taste bitter if it gets in your mouth or nose (noses don't taste but it still irritates you) so you won't be tempted to use it wrong.

Well, I was using it for something or another and got it upside down on my desk by accident. Or, more likely, I was just having fun flash-freezing things with nothing better to do. Trying to freeze coins together in the puddle of evaporating liquid or something. But anyway... THAT STUFF GETS EVERYWHERE.

The bitterant is like an oil of some kind. It is all but invisible -- but you can't get rid of it. Water won't clean it, 409 won't clean it... I was ready to BURN my desk. It gets on your fingers. Everything you *touch* gets that bitter stuff on it. Taking a bath with soap and water doesn't get it off the first time. You literally can't eat anything with your hands for about twelve hours after you've been exposed to the stuff. Everything tastes like the bitter stuff. And it's not just mildly bitter. It's revoltingly bitter. If you lick a finger after you've gotten the stuff on it, it just turns you absolutely inside out.

I guess spraying it as air is safe enough. To this day, I refuse to buy or use the stuff. That was such a horrible experience (admittedly, if I hadn't been playing with it, the stuff wouldn't have gotten all over everything, but... who doesn't spray the stuff at something just once to watch it evaporate, really?) that I haven't purchased any of it since. Partially in protest and partially just because I don't ever want to see the stuff again. I clean my computer out with the air blaster on the air compressor in the garage now.

Using it as canned air in the vertical position is probably still okay. But if you ever spray it sideways or upside down even once, and the bitter stuff comes out with the freezing liquid spray... you'll never use it again. It gets EVERYWHERE and everything you touch becomes repulsive for a day and a half.

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~Michael S.~
Past cars:

1986 300SDL
1987 300SDL
1982 240D
1982 300SD


Current:

1987 300SDL

It is a brand new gasket that I got from ********.com and is exactly the same as the previous one on there. It is rubber I suppose, but it is a very hard rubber..almost like plastic. Its flexible, but I've always been used to either using cork or a soft rubber in my past experiences.

That is weird. I remember the gasket I got from Phil being very pliable and soft to the point that it would just fall off the valve cover while I was trying to position it over the head. I remember a few obscenities sliding out of my mouth in the process too. I can't remember the manufacturer of the gasket.

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AJ

1985 300D (SOLD)

To, hold the Gasket onto the Bottom of the Valve Cover,whilst you position it
and torque it down.

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'84 300SD sold
124.128

Why is the gasket hard? It should be rubber also.

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'85 300D Cal 280,000 miles
'14 GLK 350 60000 miles

Those studs are available from your local dealer, or a pic-n-pull if you're lucky, you need two each of the short and long.
I used a stud/bolt remover to get the studs out I couldn't by double nutting them, that will destroy the stud tho. The one stuck on the cam cover should be able to be removed by the double nut procedure.
And yes, the gasket should not be hard, a new one is in order.

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83 SD

84 CD

EGAD! Try applying a little heat, with a propane torch, to the head area surrounding the stud. You don't want to get it hot, just warmed a little. Too much and you can damage the head.

Note: When you install a new cam cover seal, the torque recommendation is 14Nm/10Ft-lbs. Overtorquing can cause the seal not to work properly as well.

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Sam

84 300SD 350K+ miles ( Blue Belle )

Another place to check is Fastenal. They are nearly everywhere and have online website ordering as well.

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Sam

84 300SD 350K+ miles ( Blue Belle )