New sunroof mechanism to replace early one
02-11-2018, 01:17 AM
#1
Rennlist Member
Thread Starter
New sunroof mechanism to replace early one
My apologies if this has been covered somewhere before, but I did a search and came up empty...
Is it possible to replace an early sunroof mechanism with a late version one?
I have a 1986 model car according to VIN, but the mechanism in the rear is the early mechanism and I think it needs to be replaced.
However, almost all of the available mechanisms on the usual auction site are later version ones.
Is it a one-for-one replacement? Or do I need to find an early version mechanism?
Is it possible to replace an early sunroof mechanism with a late version one?
I have a 1986 model car according to VIN, but the mechanism in the rear is the early mechanism and I think it needs to be replaced.
However, almost all of the available mechanisms on the usual auction site are later version ones.
Is it a one-for-one replacement? Or do I need to find an early version mechanism?
02-25-2018, 12:33 PM
#4
Rennlist Member
Thread Starter
I do. I guess what I'm wondering is if it's a one-for-one replacement, or if I need to modify the length of the screw drive cable or anything...
02-28-2018, 10:15 PM
#5
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Location: Scotch Village, Nova Scotia, Canada
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yep, one for one...sort of. lol. The later one is quite different, but everything lines right up. I have an early 85, with a 88 sunroof mechanism. I did the swap a few years ago, and don't remember it as being difficult.
Good luck!
Gord.
Good luck!
Gord.
04-28-2018, 01:56 PM
#6
Rennlist Member
Thread Starter
Ok... So for anyone in the future who wants to try this, my experience was absolutely not a straightforward swap. Or at least, it wasn't on my car.
Here is what you will need:
1) A working late model mechanism
2) A late model drive cable
3) A late model drive cable guide tube
4) Appropriate tools - I had a 21mm socket to manually move the late model mechanism, screwdrivers, needle nose pliers (switch adjustment), multi-meter (to test switch positions before I powered up) and probably some others I'm forgetting.
The reason you need a late model cable and tube is that the mount points for the end of the tube where it meets the mechanism are different on the early model vs. the late model. So, you'll either need to replace the entire guide tube or you'll have to MacGyver it. If you don't somehow mount the tube solidly in the mechanism, when you go to open the sunroof, there's a good chance that it will just push the tube right out of the mechanism and your sunroof will go nowhere.
You'll need a late model drive cable because the early one also has a different interface where it meets the mechanism than the late one. The early one is sort of cut in half to limit rotation, and the late one is a full square profile. I couldn't for the life of me get my early model drive cable to fit into the late model mechanism, so rather than risk breaking my new mechanism, I just opted to buy a late model drive cable new.
Here are the steps I went through.
1) Separate the drive cable from the early model mechanism and remove the old mechanism
2) Remove the early model drive cable - The easiest way I found to do this was to mount it in my cordless drill and spin it like a huge screw. Note that it is reverse threaded, so you need to spin CLOCKWISE to remove it and COUNTER-CLOCKWISE to put the new one in. Before you remove the cable, measure the length that extends past the end of the guide tube. This will give you a ballpark for how far to install the new one.
3) Remove the early model drive cable guide tube. This involves taking trim pieces off inside the car.
4) Install the late model drive tube - just the reverse of what you did before.
5) Cut the new drive cable to length - You may not have to do this, but my original cable was about 8 inches shorter than the new one, so to get it all to work I had to cut it.
6) Install the new drive cable using the cordless drill rotating COUNTER-CLOCKWISE until you have the same length of cable extending out of the new drive cable guide tube. You may have to adjust this for the new mechanism. In fact, there's a 90% chance you will as the new mechanism doesn't use the same length of cable as the old one. You will probably find that you need to attach your drill and counter-clockwise twist more of the cable into the roof to get it to fit. YMMV.
7) Install the new drive cable in the mechanism.
8) Mount the mechanism. Only one mounting point worked on my car. I went with that.
9) Spend the next hour our so making sure the limit switches click on at the right time.
10) Test, and test again making necessary adjustments to the limit switches.
It's worth noting, as I said in step 8, that the mounting holes on my car for the old mechanism didn't line up with the new mechanism at all. I mounted it with one mount rather than two instead of drilling a hole in my car for the second mounting post.
That's about it. It was a very, very fiddly job and took a lot of patience and slow going. I performed the open heart sunroof mechanism transplant over a period of about two weeks working slowly and deliberately. It can be done, but it's certainly not a "pull it out, drop another in" job, or at least it wasn't on my car.
However, the advantage is that there are many, many more late model mechanisms to be had if the one you have fails. I was unable to find a decent early model mechanism that I thought might work for the next ten years, which is why I went ahead and performed this job.
Good luck!
Here is what you will need:
1) A working late model mechanism
2) A late model drive cable
3) A late model drive cable guide tube
4) Appropriate tools - I had a 21mm socket to manually move the late model mechanism, screwdrivers, needle nose pliers (switch adjustment), multi-meter (to test switch positions before I powered up) and probably some others I'm forgetting.
The reason you need a late model cable and tube is that the mount points for the end of the tube where it meets the mechanism are different on the early model vs. the late model. So, you'll either need to replace the entire guide tube or you'll have to MacGyver it. If you don't somehow mount the tube solidly in the mechanism, when you go to open the sunroof, there's a good chance that it will just push the tube right out of the mechanism and your sunroof will go nowhere.
You'll need a late model drive cable because the early one also has a different interface where it meets the mechanism than the late one. The early one is sort of cut in half to limit rotation, and the late one is a full square profile. I couldn't for the life of me get my early model drive cable to fit into the late model mechanism, so rather than risk breaking my new mechanism, I just opted to buy a late model drive cable new.
Here are the steps I went through.
1) Separate the drive cable from the early model mechanism and remove the old mechanism
2) Remove the early model drive cable - The easiest way I found to do this was to mount it in my cordless drill and spin it like a huge screw. Note that it is reverse threaded, so you need to spin CLOCKWISE to remove it and COUNTER-CLOCKWISE to put the new one in. Before you remove the cable, measure the length that extends past the end of the guide tube. This will give you a ballpark for how far to install the new one.
3) Remove the early model drive cable guide tube. This involves taking trim pieces off inside the car.
4) Install the late model drive tube - just the reverse of what you did before.
5) Cut the new drive cable to length - You may not have to do this, but my original cable was about 8 inches shorter than the new one, so to get it all to work I had to cut it.
6) Install the new drive cable using the cordless drill rotating COUNTER-CLOCKWISE until you have the same length of cable extending out of the new drive cable guide tube. You may have to adjust this for the new mechanism. In fact, there's a 90% chance you will as the new mechanism doesn't use the same length of cable as the old one. You will probably find that you need to attach your drill and counter-clockwise twist more of the cable into the roof to get it to fit. YMMV.
7) Install the new drive cable in the mechanism.
8) Mount the mechanism. Only one mounting point worked on my car. I went with that.
9) Spend the next hour our so making sure the limit switches click on at the right time.
10) Test, and test again making necessary adjustments to the limit switches.
It's worth noting, as I said in step 8, that the mounting holes on my car for the old mechanism didn't line up with the new mechanism at all. I mounted it with one mount rather than two instead of drilling a hole in my car for the second mounting post.
That's about it. It was a very, very fiddly job and took a lot of patience and slow going. I performed the open heart sunroof mechanism transplant over a period of about two weeks working slowly and deliberately. It can be done, but it's certainly not a "pull it out, drop another in" job, or at least it wasn't on my car.
However, the advantage is that there are many, many more late model mechanisms to be had if the one you have fails. I was unable to find a decent early model mechanism that I thought might work for the next ten years, which is why I went ahead and performed this job.
Good luck!