Stuck on oil cooler job because of mounts - PeachParts Mercedes-Benz Forum

JHZR2 · #1 02-15-2010, 08:47 PM

Hi,

Started the oil cooler line job on my 82 300CD. Had high hopes to be able to get them out without removing the mount, as some folks on benzworld were able to... And my mounts were more or less new.

Well, I cannot see any way that can happen. Between the AC compressor and the shock and arm for the engine mount... There really is no space.

OK, so, the good news, got my car lifted and on jackstands. Got all four oil cooler hose fittings off without any issues. That is a major plus. Wrested with the hoses, flipping them any which way - no dice.

Unbolted the bottom 8mm allens to start to get the mount out - no other solution I could see. Could get the outer 6mm bolts out, but there is ZERO space to do the inners. I can get a 6mm allen socket into the hole, but the motor mount arm that attaches to the block is in the way of getting an extension, U-joint, etc. on there. I can get an 'L' allen key in there, but even torquing on the long arm, I cannot get enough leverage, or get anything else on it to give me more.

The diesel giant instructions dont give any other steps. What else do I need to do to get the inner mounts? I am about to just unbolt the arm from the engine block, and see where that takes me.

Any recommendations? I started at 330 today, and 5 hours later, I only have the oil cooler hoses unbolted and the 8mm allens out.

Thanks!

Diesel911 · #2 02-15-2010, 09:11 PM

Sounds like you will find a way to do it. Going back to Diesel Giant he sells a cut off Allen Wrench that is used somewhere down there. Perhaps you could cut your own. Look at the pic on his site and see if cutting yours would help.

JHZR2 · #3 02-15-2010, 09:23 PM

He shows a ground wrench which is necessary to get the hose fittings loose. I got past that. Didnt see any specialy allen wrench tools.

Is it just me or must the shocks be removed prior to being able to access the inner bolt? I have a feeling that access to the inner hex bolt is under the shock mount on the engine mount arm...

beermc00 · #4 02-15-2010, 11:59 PM

I just ran into the same problem you are having. My Air Force diesel mechanic friend, my brother and I spent one and a half days trying to figure out how to get to that damn allen bolt on the engine mount. My friend gave up and I was left with disconnected oil cooler lines, jet black oil everywhere and lots of frustration.

My brother and I decided to take the shock mount arm off the block out of desperation thinking it would be a horrid job. We used a ratchet (17mm I think) and the end of my hydraulic jack for extra leverage on the ratchet handle. I had the arm off in 10 minutes...it was actually simple, plus it made installing the new lines that much easier. Definitely remove the arm.

It is a very fulfilling job once it is completed successfully. Good luck!

JB3 · #5 02-16-2010, 12:02 AM

I took a allen key head that fits in one of those selectable head wrenches, you know what im talking about, like 3/4 inches long. The ones you buy in packs and whatnot.

I used one of those and slid a box head wrench that fit around it to slowly unscrew the bolt. Tedious, but it worked like a charm, then I was able to jack the motor up just enough to get the oil cooler lines out and in.

tangofox007 · #6 02-16-2010, 12:08 AM

Quote:

Originally Posted by JHZR2

Unbolted the bottom 8mm allens to start to get the mount out - no other solution I could see. Could get the outer 6mm bolts out, but there is ZERO space to do the inners.

There is no need to remove the mount from the frame. Just remove the bolt from below, disconnect the engine shocks and lift the engine.

babyjames · #7 02-16-2010, 02:35 AM

Put a little lube on the end of the socket head bolt from underneath - you can just sorta' see it if you look close.

Remove the clips holding the fan shroud to the radiator so the fan doesn't break the shroud when you lift the engine.

Put a chunk of 2x6 between the saddle of your floor jack and the lower oil pan and jack the engine up a little. You can now remove the sheet-metal heat shield that sits on top of the mount - just pull it out of there.

Now you should be able to get to the inner socket head bolt. I use a LONG 1/4' extension, a short wobble extension and a ball-end hex driver. If all you have is an M6 ball-end (L-bend) you can put the ball in the bolt and then use a 6mm deep socket on the short leg of the "allen wrench" and an extension in the socket for leverage.

On reassembly, I use blue loctite and just snug the little bolts up. They're not going anywhere. Loctite on the big bolts, too, but I make them pretty tight.

You got the big bolts out without stripping them, so you're over the hump. You'll get it....

Jay.

JHZR2 · #8 02-16-2010, 08:28 AM

Thanks for the replies...

So the heat shields come out just by pulling? I guess they are just held in by friction/mass of the engine?

I jacked the engine up without disconnecting the shocks. I only did it enough that the fan nearly touched the shroud in its usual spot. Is this sufficiently high to bend the shock rod or damage them? My car has two shocks.

Also, when lifting the engine, I used two 2x10s cut a bit over a foot long. When jacking, I suppose especially since the car was only on jackstands in front, the board only contacted the oil pan in the rear half, where it appeared flatter. No apparent damage done, and I did use wide boards, but is something wrong there?

Is there a best practice to test the functionality of the engine shock and mount when it is out of the car? After 159k, they looked good/clean, but I'm not sure if a visual from the top is the right verification...

Thanks again!

charmalu · #9 02-16-2010, 08:00 PM

Before you lifted the engine, the nuts on the lower end of the engine shock should be removed. there is a flat on the shaft that a 7mm open end fits on to keep the shaft from turning when removing the 10mm nut on the end.

make sure the shafts line up with the mount hole when lowering the engine, or the shock will be pushed up through the upper mount. I learned that one the hard way.

think that upper mount is like $50 each. or just remove the 2 upper mount bolts.

the shield just sits in between the engine mount and the engine arm. then the 8mm bolt from underneith holds it together.

next time you do the oil lines, just cut them off with a pair of loppers. makes it easier to remove the pipes. be sure to place a pan under the oil cooler to catch the mess.

when I jacked up my engine, I used a piece of 3/4in plywood the size of the pan area with a 2x8 nailed to it on the under side to jack against. this way I used the whole pan area to push against.

Charlie

JHZR2 · #10 02-16-2010, 08:31 PM

Thanks. I plan to R&R the shocks after testing that they are still functional. This should prevent any issues.

So I guess the question still is, is the removal of the heat shield mandatory to remove the mount? Or more specifically, required to access and be able to apply suitable torque on the inner 6mm hex? I can get an L Allen on the bolt, but not enough torque to move it.

I did do the 2x10 boards on the oil pan, but I guess what I see is that there is a taper to the pan, so in reality it seems that only about half of the pan (rear half) actually contacts the board. This has todo I think with the taper of the pan (not totally flat-bottomed), and the fact that a car on jackstands in front has an angle compared to the flat board on a Jack with wide contact base parallel to the ground...

tangofox007 · #11 02-17-2010, 12:21 AM

Quote:

Originally Posted by JHZR2

So I guess the question still is, is the removal of the heat shield mandatory to remove the mount? Or more specifically, required to access and be able to apply suitable torque on the inner 6mm hex? I can get an L Allen on the bolt, but not enough torque to move it.

Unless you are replacing the mounts, there is absolutely no need to remove the mounts or the heat shields from the frame.

JHZR2 · #12 02-17-2010, 12:54 AM

Well, just removing the 8mm bolt, I didnt get clearance jacking the engine only high enough that the fan barely doesnt touch the shroud... Do I need to go higher? These are new mounts...

Or perhaps since I didnt unbolt the shocks, I restrained things a bit. Hope I didnt damage the shocks too bad...

tangofox007 · #13 02-17-2010, 12:58 AM

The fan shroud can be "unclipped" in about five seconds. Definitely unbolt the left engine shock and disconnect the throttle linkage at the firewall. (I leave the right engine mount and shock connected and just jack up the left side of the engine.)

JHZR2 · #14 02-17-2010, 01:22 AM

OK, one more dumb question... How do you just jack up the one side of the engine if using a huge board to spread the force?

cmbdiesel · #15 02-17-2010, 02:45 AM

Quote:

Originally Posted by JHZR2

OK, one more dumb question... How do you just jack up the one side of the engine if using a huge board to spread the force?

I used a pole jack and a roughly 10" square piece of 3/4 plywood. The jack was off center and it seemed to work pretty well, but my SD was on a lift...

You have already spent more time trying to get the lines out without unbolting the mount and shock than it would have taken to have just done it. But, don't feel bad, I did the same thing. Worse than the first attempt at Rubik's cube...Trying to get them out with everything in place is as close to impossible as anything I've tried....

Thread Tools
Show Printable Version Email this Page
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode