Mercedes-Benz Forum banner

1 - 8 of 8 Posts

·
Registered
'82 300GD TD (Sold), '02 G500, '09 B200
Joined
·
485 Posts
Discussion Starter #1
I have been trying madly for a while now to stop all of the oil leaking out of my G. I have nailed down several of the leaks but still have one persistant leak on the top of my oil pan (om617A) where it connects to the block. Is there anything to taking this thing off with the engine still in place and putting a new gasket in there and just putting it back on or is it holding anything else in (front or rear main seals, etc)? I realize this may not be the best forum for this question, you guys are just so much more civil to deal with[:)].

The unfortunate part is (and the reason for the leak) that there is a broken off bolt stuck in the block that has to be removed first[:(!].

Steve
 

·
Registered
300GD 500SL 300E
Joined
·
232 Posts
Do not feel bad mine leaks to.[:p]
 

·
Registered
85 300GD 83 300TD
Joined
·
978 Posts
Hi Steve, the job is not that easy to do. I pulled my pan off to get at the pressure relief valve on the pump in the stock 300 non turbo. It requires removing the skidplate, the drag link and the most difficult part; the dipstick tube. There is no gasket mating the pan with the block. It is a machined flat surface fit using a sealant like Hylomar which is what I used. The trickiest part of the project was getting the dipstick tube back in and seated. I created a little lever assembly to do it. It is no fun. Prepare to stare at the bottom of the motor on your back removing many allen head bolts, some of which cannot be reached with a rachet. In those areas I used an allen wrench 1/8 of a turn at a time. The front main seal stays where it is and the rear is a two piece, half of which sits in a recess area in the pan. Mine went together without a problem in the main seal areas. I used a bit of Hylomar where they contact the pan. Is the broken bolt in an accessable area so you can use a drill and an easy out?

-Dai
 

·
Registered
'82 300GD TD (Sold), '02 G500, '09 B200
Joined
·
485 Posts
Discussion Starter #4
Thanks guys,

Looking at it more, there a few sheared off bolts. Two are easy to get at, one might be tricky. Removing a few steering parts, skid plate, etc, shouldn't be too bad. Gasket making material is easy enough to use and I have lots of it. I think it really is time to just go out and buy an engine manual even a Haynes or something would be better than just going in blind.

I have never had to remove a sheared off bolt before. Any hints/suggestions[?][?][?].

My oil filter housing was leaking like crazy and I fixed it up. Then, after cleaning off the engine, I realized the bottom portion of my pan was leaking - fixed it up and thought all was good. This was a month or so ago. Then yesterday, a good 80 hwy kms from home, I started heating up and losing oil pressure. I pulled over and oil was spraying all over the place and smoking (and stinking) like mad. Luckily, I had a jug of oil in the G (always prepared) and topped it up and limped home, filling as necessary. Not fun!

Steve
 

·
Registered
111.010 121.942 202.033
Joined
·
1,850 Posts
sjtymko - 4/16/2005 1:15 PM

Thanks guys,

Looking at it more, there a few sheared off bolts. Two are easy to get at, one might be tricky. Removing a few steering parts, skid plate, etc, shouldn't be too bad. Gasket making material is easy enough to use and I have lots of it. I think it really is time to just go out and buy an engine manual even a Haynes or something would be better than just going in blind.

I have never had to remove a sheared off bolt before. Any hints/suggestions[?][?][?].

My oil filter housing was leaking like crazy and I fixed it up. Then, after cleaning off the engine, I realized the bottom portion of my pan was leaking - fixed it up and thought all was good. This was a month or so ago. Then yesterday, a good 80 hwy kms from home, I started heating up and losing oil pressure. I pulled over and oil was spraying all over the place and smoking (and stinking) like mad. Luckily, I had a jug of oil in the G (always prepared) and topped it up and limped home, filling as necessary. Not fun!

Steve
You may have to drill it out and re-tap it or possibly use a heli-coil. Sears Craftsman has a few gizmos to assist w/ broken bolts. I have never tried them.

When I rebuilt the entire suspension and subframe on my 1966 I was amazed how well everything came apart. I don't know what type/grade of bolts MB used or if they had applied a lubricant but it sure is a lot easier working on a 40 year old Mercedes than a 10 year old Chevy.
 

·
Registered
85 300GD 83 300TD
Joined
·
978 Posts
It sound like you are leaking oil under pressure. There is no pressure at the pan/block mating surface. Try using a can of Foamy engine degreaser on the engine and pressure washing the thing clean and then try to determine where exactly the oil is coming from. I would suspect oil cooler hoses or fittings. The pan mating joint should not leak a high volume of oil unless it is loose city.
To get a broken bolt out I use a small cobalt drill bit to bore up into the middle of the bolt. I use a center punch to get an accurate start. There are tools called easy-outs or bolt extractors that looks a bit like a tapered drill bit with reverse thread spiral flutes on it. You use a drill bit sized to the easy-out, drill the bolt part way in and then tap the easy out in there lightly with a small ball peen hammer. The tool is designed to grip the bolt so it can be unscrewed anti-clockwise. I grip the end of the tool with a small vice grip or tap handle. The broken off bolt is usually not under tension because it is missing its head. Small bolts like the pan allen heads are tricky because the small easy outs are fragile and brittle. Do not break the tool off in the bolt. This creates a larger problem. To get the tool out of the bolt grip the bolt in a vice or locking pliers and turn the tool clockwise. I have had success removing small broken bolts sometimes by drilling a hole in the end and reversing the drill motor with the bit in the bolt and slowly spinning it out. Only works sometimes. If you go for removal of your pan you may have a small amount of the bolt sticking out of the block that can be gripped with a locking plier and spun out of there.
There are a couple of different styles of screw extractors. Another type is a tapered square profile thing that you pound ito the hole in the bolt. I've had the best luck with the type I first described. On bolts that are really stuck I've had another bolt welded to the stuck one.

-Dai
 

·
Registered
2000 G500 NMLE
Joined
·
6,977 Posts
Fastener Quality

mb230s - 4/16/2005 3:23 PM

I don't know what type/grade of bolts MB used or if they had applied a lubricant but it sure is a lot easier working on a 40 year old Mercedes than a 10 year old Chevy.
It's the grade (quality) of the electroplated finish on the fasteners that makes the difference. No or little corrosion equals easy removal on down the line.
 

·
Registered
1980 LWB 280GE
Joined
·
3,504 Posts
How's your oil pressure switch? It's at the base of the filter housing on the 617A and would account for the area of the original leak as well as the spraying you see now. They're known to crap out eventually and fail in various ways. For my 617A I made an adapter to turn the 12mm x 1.5 thread to a 1/8" pipe and then bought a $5 pressure switch to go on a Tee along with the sender for the gauge I bought.

If you do need an oil pressure switch, the one that fits the 617A and will light the G's light is a BMW part available for about $10 from Checker/Kragen/Schucks. Ask to look through their oil pressure switch book until you find a BMW aplication that fits a 12mm x 1.5 thread and looks like a little mushroom with a threaded rod sticking out the top. I might be able to find the number somewhere.

The sender for the regular 617 and for the M110 is a little different. Also available at Checker though. Sadly, it's about $25. It's a 14mm x 1.5 thread and has a phillips screw in the top rather than the rod sticking out.

Finally got the turbo seal I needed today and got the turbo back together and bolted up to the exhaust manifold. I paid the price for the two week break between disassembly and reassembly though and had to repeat some steps after getting ready to put the turbine housing on and discovering I'd forgotten the clamping ring, which can't be assembled with the turbine in place...so I got to do that over. All fine in the end though and I should get everything bolted up to the block tomorrow and be able to send a pic of the assembled motor.

-Dave G.
 
1 - 8 of 8 Posts
Top