Finally fixing the subframe

[JimFreeh]

After five years of sitting around, I'm finally getting the subframe fixed on my 84 280SL. Got the parts a few years ago, but didn't get around to bracing the new subframe until a month or so ago.

Got the MB reinforcements welded onto a subframe from a W114 250.

The only glitch so far, is that I need to drill a couple of holes to provide access to the bolts for the motor mounts. (The bolt comes in from the bottom on the SL engine mount.)

Dropped the subframe tonight, and got the springs out.
Finish up the disassembly tomorrow...

Jim

[JimFreeh]

Old ball joints removed, got the new ones pressed or bolted into place.
New upper and lower bushings, new subframe mounts and anti roll bar bushings. Then install the new Bilsteins to match the new ones in back.

Time for reassembly.

After the subframe is in, it's on to the drag link, tie rod ends, idler arm and steering shock

If I'm lucky, I'll be able to let her down of the stands this week.

Jim

[JimFreeh]

Here's what I've learned:

Both W114 and R107 mounts bolt to the subframe using the same bolt pattern.

W114 motor mounts have a female thread in the center that accepts a bolt that is dropped down thru the motor mount arm.

The R107 mount, (at least for the euro 280SL) has a smooth bore, and you install the mounting bolt from the bottom, using a caged nut on top of the motor mount arm.

I imagine this is done for clearance, since there effectively isn't any at the top of the arm....

The subframes are the same with one difference:

The lower access hole in the R107 subframe is not present on the W114 subframe. Oddly, the upper one is present on both.

In my favor, the W114 subframe has a stamping that locates where the hole needs to be drilled. I used a 1" hole saw to make the holes.

The R107 also has these neat sleeves that install into the subframe before the motor mount, and these things consist of a cylinder that fits between the two access holes. Keeps the bolt from getting lost inside the subframe. Pretty cool, eh?

Now I'm ready for reassembly, Woo Hoo!

Oh, another trivia item: The upper ball joints have two possible bolt patterns. You have to grind off the rivets mounting the original ball joint and source some fasteners (3) to install the new ball joint. Make sure you use high strength fasteners! Anyway, there is a big and small pattern, make sure you measure which one you have before ordering! I didn't. Fortunately, I had another set of upper control arms with the correct pattern, only cost me a couple of hours worth of disassembly.

Jim

[nobby]

Originally Posted by JimFreeh

Here's what I've learned:

Both W114 and R107 mounts bolt to the subframe using the same bolt pattern.

W114 motor mounts have a female thread in the center that accepts a bolt that is dropped down thru the motor mount arm.

The R107 mount, (at least for the euro 280SL) has a smooth bore, and you install the mounting bolt from the bottom, using a caged nut on top of the motor mount arm.

I imagine this is done for clearance, since there effectively isn't any at the top of the arm....

The subframes are the same with one difference:

The lower access hole in the R107 subframe is not present on the W114 subframe. Oddly, the upper one is present on both.

In my favor, the W114 subframe has a stamping that locates where the hole needs to be drilled. I used a 1" hole saw to make the holes.

The R107 also has these neat sleeves that install into the subframe before the motor mount, and these things consist of a cylinder that fits between the two access holes. Keeps the bolt from getting lost inside the subframe. Pretty cool, eh?

Now I'm ready for reassembly, Woo Hoo!

Oh, another trivia item: The upper ball joints have two possible bolt patterns. You have to grind off the rivets mounting the original ball joint and source some fasteners (3) to install the new ball joint. Make sure you use high strength fasteners! Anyway, there is a big and small pattern, make sure you measure which one you have before ordering! I didn't. Fortunately, I had another set of upper control arms with the correct pattern, only cost me a couple of hours worth of disassembly.

Jim

Nice work. How did you get the springs out with the subframe removed?

And the upper ball joints I bought from mercedessour*e came with the hardware.

[rowdie]

Upper right of picture #5. Looks like spring compressor. Works from top but not from bottom.

[JimFreeh]

Originally Posted by rowdie

Upper right of picture #5. Looks like spring compressor. Works from top but not from bottom.

Correct, used the Klann spring compressor.

The lower control arm does not have a large enough hole in it to fit the compressor shaft inside the spring. Need to come in from the top, which means that the subframe has to be removed before installation because the inner fender is solid above the upper spring perch.

Been cleaning the parts, hope to get some painting done tonight. I think my wife has other plans this weekend, might slow me down....

Jim

[rowdie]

Jim

I found that out "AFTER" I bought the spring compressor.

Jim

[JimFreeh]

When I disassembled the car, I noted that the anti-sway bar mount on the right hand side was perilously close the the RF subframe mount.

What a PITA the sway bar turned out to be. I was concerned that if I installed it first, I'd block the RF portion of the subframe.

Installed the subframe first, then pretty much had to remove it again whilst fitting the anti-sway bar.

Tired, greasy and sore, that's it for tonight.

I'll continue tomorrow and tackle the engine mounts and reinstallation of caliper, antiskid lines and brake wear lines.

Then get some weight on the suspension and tighten up the fasteners.

The tie rods, drag link and idler arm may have to wait for a couple of weeks, as this is really dragging out much longer than I had thought.....

Jim

[JimFreeh]

Just about there....

Jim

[JimFreeh]

Now need to let the suspension settle, then tighten up all the rubber...

Jim