Door check strap - PeachParts Mercedes-Benz Forum

Bruce Bonds · #1 07-18-2004, 03:22 PM

I would like comments from the forum about an idea that I have. My d/s fnt. door has the common problem of hellacious poping and clacking noise. As most of you know, this noise is caused the piece that holds the check strap retaining pin. It has separated from the body and makes loud clacking noises each time you open and close the door.

Currently, I am running in the silent door mode. I just removed the check strap all together. Boy it's quiet.

The check strap has two functions. It gives you a mid swing stop point and it prevents the door from swinging open two far and thus putting stress on the hinges.

I can do without the mid-swing stop point but I don't want to screw up my hinges in a high wind.

Here is my idea. Rather than welding the piece back to the inside of the body (the correct fix but a major PITA), I want to alter an old check strap so that it will just keep the door from swinging open too far.

Picture this. Take an old check strap assembly. Put it on a piece of wood. Take a hammer and hit the strap at an angle hard enough to dislodge the ball bearings and springs. Throw away the springs and ball bearings but try to keep the rubber bumpers on the sliding barrel. Now you have a door check strap that it not spring loaded and shouldn't cause the the retaining pin holder to clack and pop against the body. I am about to install my "new" and hopefully quiet door check strap and see how it works.

Remember, my only goal is to have a quiet, easy, and cheap method of keeping my door from swinging open too far and fast, thus putting stress on my hinges. I'll keep you posted.

Palangi · #2 07-18-2004, 08:18 PM

Let us know if this works. I have the same problem. I had thought about filling in the middle detents with something, but I can't think of any filler material that take the beating.

Bruce Bonds · #3 07-18-2004, 09:11 PM

Palangi, look at the pin that holds the check strap to the car's body. The pin goes through a piece with two holes. This piece is welded to the body from the inside. You can't see the welds, but if they are broken, you can see the piece moving back and forth when you move the door. This is what makes the clacking popping noise that I needed to silence. If this piece is still firmly attached, your noise is probably a scraping noise from a worn out check strap assembly. I have replaced four out of my eight in the last two days. The issue that got me started was the SD door was stuck open and I had to do something. Glad it was in my driveway at the time and not in front of some fancy resturant in the rain. So check and see if it is the pin holder on the body or the check strap assembly inside the door that's making noise.

Palangi · #4 07-18-2004, 09:23 PM

Yeppers, same problem. The weld is broken inside the fender panel. I got a new strap and loaded the 4 detents with grease. That quieted the noise a little, but of course did not fix the root problem. As I said, I thought about filling in the middle detents with something, but I don't know of any material which could take the beating. Your idea is probably better, but I don't know how the strap that goes to the pin will stay in place well enough to limit the door. So, let us know how it works.

Bruce Bonds · #5 07-18-2004, 10:20 PM

Palangi, I want you to try wiring the pin first. I did it after I modified my check strap so I can't say if it works with a fully functional check strap or not. Take about six inches of steel wire like baling wire or a thin coat hanger. The wire has to be just the right thickness to squeeze between the body and the pin, at the top and bottom of the pin. Wrap the wire and get it as snug as you can. The idea is to keep that pesky pin holder from popping in and out. I have mine wrapped now and it does not move however, there's no force against the pin because I removed the springs and bearings from my check strap.

If this doesn't work: you said you put on a new check strap. Don't modify your new one. Check the other doors and take out an original and replace it with your new one. I modified an old check strap that was still intact. There is a springloaded cylinder w/a ball bearing and rubber bumper on each end. The cylinder has to be tilted within it's track to get the bearings and the spring out. It looks and feels impossible. I tried all sorts of ways before resorting to the hammer. Here's what you do. Seenext post.

Bruce Bonds · #6 07-18-2004, 10:37 PM

Place the check strap assembly on a flat hard surface on its side. Fold the strap and the track assembly into a V and it will balance on it's side. Now strike the strap on the top edge hard at an angle that will cause the cylinder to tilt enough for the bearings and spring to pop out. The cylinder is large enough to stay within the tracks and it stops the door swing at the same place as it did before. I am happy with the way mine works and it is silent. Oh, I discovered one more function of the check strap. It keeps the door open. My door will not sit open but swings closed when I let it go. I guess this is OK for the driver door since I won't be loading groceries there. Hope this helps.

thebern · #7 07-19-2004, 08:49 PM

A while back I had the same problem and posted a fix. Basicaly drill a 1/4" hole in the middle of the door piller. Hold the little mounting bracket in place with a coat hanger and 'pool weld' into the hole. Beware of the vacuum lines behind there, they melt.

thebern

ak300td · #8 07-19-2004, 09:13 PM

My check strap died and the door got stuck open but mine failed when the strap got bent. I was wondering if the strap somehow got wedged into the track and when I attempted to close the door it bent the strap. Sound plausable?

Palangi · #9 07-19-2004, 09:15 PM

Bruce

I beat on a little today, but can't really get a good angle on it with it just laying on a flat surface. I am going to try clamping it in a vise so I can strike some heavy but controlled blows on the cylinder, using a heavy hammer and a chisel. I think if I hit the cylinder just right, I can do it. It may be a couple days before I get a chance to try this.

By the way, when the spring and bearings get loose, is it gonna blow a hole through the garage wall? I think I will wrap the whole thing in a towel to slow down any flying parts.

Bruce Bonds · #10 07-19-2004, 09:55 PM

Don't worry. The cylinder never leaves the track so the bearing and spring never get airborne. But that is a funny thought.

Palangi · #11 07-25-2004, 11:07 PM

Well, I had to resort to the hammer / chisel / vise method, but I was able to knock the cylinder sideways so the spring and bearings fell out. It took more force than what I expected.

Door now opens and closes smoothly and quietly. Only problem is, like you said, the door won't stay open, but that's really not a problem unless it's windy.

Thanks for posting your idea. It motivated me to fix this, and I am quite pleased with the results.

Bruce Bonds · #12 07-26-2004, 11:15 AM

My pleasure, glad it helped. Coincidentally, I just had another check strap failure w/o any warning noises. Rear door would not close. When this happens, the only way you can close the door is to get the jammed check strap out of the way. I removed the check strap and "modified" it with my hammer as in previous posts and I am using it like this until I get a new one installed. I was lucky again that this happened in my driveway.

Palangi · #13 07-26-2004, 04:21 PM

Bruce

Just curious, what actually fails when that happens? I have had a few noisy ones, but a bit of grease has always quieted them down. Doesn't seem like there is anything in there to fail unless it was run dry for years.

Bruce Bonds · #14 07-26-2004, 09:19 PM

I wish I knew. I've had them fail with and without that noise. Of the three that I have had stuck open, only one appeared damaged and broken. The other two "looked" OK and were well lubricated, but I could not budge them out of the front detents and close the door. How and why these two jammed is still a mystery. I'm considering just "modifying" the other two on my daughter's car so I won't have to worry about her getting stuck with an unclosable door at college 4 hours away. It will be easier than teaching her how to remove the check strap if it jams. By the way, she is sure happy that the clacking and popping noise is gone from the fnt. d/s door.