1991 300sl soft top rod is not connected,see pic please

[rp930]

new owner of 1991 300 sl, I think I have identified the part to be 129-770-21-14 on epc. I'm asking for help to determine why it came loose. when i lower the top it tries to fold towards front instead of back. please see pics. I only put the top up twice, so I don't know if this broke loose when I did it or if was already done. need to find out why this happened so I can repair. thanks good members

[97 SL320]

I can't offer SL specific advice as I have not yet removed my hard top / operated the soft, but can offer how this type of swivel joint works.

There are basically 2 types of this joint. One that is staked together and one that the joint can be removed from the ball. A riveted ball is generally a sign the joint comes apart. If bolted, it can go either way. Removable joints are similar to a throttle cable end.


Take a look at the ball, is it riveted to the top frame or is it a bolted connection? ( a hex makes a bolted connection likely )

If the joint is staked, it likely wore out or jammed. Was there any evidence that the leading edge of the top hit something? ( Like the top was operated in a low garage sometime in the past? ) The rod being very bent makes me think the top met resistance.

If the joint is of the removable type, there is usually a locking clip that must be removed first. This clip is a ~ 0.030" wire shaped like a bent " ? " mark that fits through two holes at the mouth of the joint. The other end clips over the body. If this locking clip is missing, the joint will eventually come apart.


There should also be a wire ring in the joint to give it snap action during assembly. ( Like a heavy snap for a bag or coat )

[tecqboy]

I had that happen to my 1991 300SL as well. I couldn't figure out why it happened, it just did. Perhaps the lubrication dried out, as there was no sign of grease in the fittings. In any case, I replaced the ball ended stud as well as the cap and it's been working fine for years. I do believe that it's a good idea to use some white grease on any of the joints which move or flex and I try to do that every other summer. This car ( 90 -93 ) has the notoriously awful soft top control computer. Much has been written on this forum on how to read out the trouble codes and reset the controller when it hangs up, which it eventually will. You can build a home built tester to read and reset the codes. It's not difficult, but it can be a PITA. Use the search function to find the info on the controller. The soft top controller interacts with the roll bar controller and the power windows. Fuses for these are located in the trunk, upper right side. Be sure to check the hydraulic fluid level of the system under the spare tire. BTW, later year models of the SL had an improved STC.