EDJ

Don't know if there's any info out there but I'm rebuilding my base power seats (no memory or lumber). I'm replacing recline cable and bezel for power switch. I also did the mod to repair sliding of track. My issue is there seems to be some binding up of the worm gear on one side when trying to move forward and backward. I measured where the block was on both sides and believe I put them back in the same position they came out. With no load on seat it moves in all directions but when I'm sitting in the seat it seems to bind up. Is there any technical info out there that describes how to properly align the gears?

Evil-Twin

you should have put a witness line on each rail and the block.. ( a piece of masking tape with a line on it that you use to line up the block with the rail on each side.. Now that you have skewed it, you are going to have to try to make both sides even , you can be off by more than one thread. I'm asking questions because I don't know who you are..or how capable you are... did you remove and clean and lube the threaded rods, and did you repack the block so there is no movement? there use to be fiber washers which deteriorate over time.. you have to load the block with nylon fill spacers.. Did you just attempt this without directions.. or guidance from someone who has done this before? Not trying to thrash you... but some time you get bad advice...or you attempt something without fully understanding how it works.. I can try to help you, but you are going to have to clean and lube, fill the block with nylon spacer ( bought mine at home depot and made them fit. gearing has to be right on the money or it will bind when under load. the fact that it works when unloaded means you are only a few turns off on one side.

I just reread your post... apparently you did not seek any guidance and are now asking for some after the fact, there are several You Tube videos that also encompass the rocking chair fix.. that problem is caused by the deterioration of the felt washers.

here is all the information you will need.
https://www.bing.com/search?q=C5+cor...be&FORM=EDGNNC

EDJ

I wasn't asking how to fix the rocking seat repair. I did research and watched videos and I did clean, lube and replace the spacers. Maybe my markings weren't exactly perfect. My question refers to when the seats are originally built there must be some specifications to correctly align the worm gears. That's what I was asking for.

Evil-Twin

I know you didn't ask about the rocking seat fix, I only offered that as a visual aide in how to remove the gears from the rack and set the blocks.. those seats are built by Lear seating in Mexico and they use a fixture to align the rack. No one has access to that fixture.
Sorry I was of no help... this is a mechanical adjustment, if you know how to measure you can align the racks.. Apparently you don't. I don't know how else to advise you.. If I had your rack here, I could align the two in 20 minutes. If you had a set of 12 inch Vernier's, you could measure to the thousands and make the other side the same within a thousandth. Everyone has a set of Vernier's don't they? I'd lend you mine if you lived close by.

EDJ

Of course we all have a micrometer, unfortunately mine is only 6", but I'm sure it'll do. I thought this forum was to help and give advice. Not criticize and insult. But thank you for the info that a jig is used. That's all I was really asking for. Pardon my ignorance.

Evil-Twin

If you are accusing me of criticizing and insulting you, and disrespecting the time I've spent to try help you then, that's on you.. Your expectations are too high.. Did you want me to come to your house and fix it for you???

You said you viewed the You tube videos and even with that, you said that maybe you didn't measure correctly. Notice, no one has helped you, told you how and where these seats are manufactured, I pointed you in the right direct and yet you tell me I am insulting you. NICE.... Thanks for the kind words of appreciation.. OH BTW, since you can't read and I understand that English, in written word, may not be your first language.. There is a big difference between a Micrometer and a Vernier .. I never mentioned a micrometer... reading and comprehension is not your strong suit... <--------since you accused me of insulting you... I thought I might as well show you what insults look like.. I tried my best to help you and you slapped me in the face.
Good Luck
Bill aka ET

You can take a ruler and measure close enough to make a proper alignment.. You need a locating face on each side that are exactly the same on both rails. you need to scribe a center line in each block. measure from the locating face to the center line, and make both side the same... easy peasy.. if you need more help or don't understand what a locating face is, or how to measure a center line, I can help you.. I would not want to be accused of insulting you. WE give advice and information here, its unfortunate that some people just are incapable of digesting what we offer..

EDJ

My apologies

EDJ

Once again my apologies to Evil Twin on my misunderstanding of his advice. We conversed thru a PM and he was able to give me very detailed instructions on what I did wrong and how to correct the problem. I meant no disrespect to him and greatly offer thanks for his help.

Evil-Twin

It was my pleasure to help you in PM, I can be sarcastic at times when my advice has been taken for granted or I've been disrespected.. It take quite a man to admit fault in open forum, I told you I would help you in open forum or in PM, and that it was your choice,., I thank you for posting that all is well...and doing so in open forum.
Bill aka ET

bngoods

So I am the lucky owner of a 1998 Corvette Pace Car (replica). First ever Corvette, at 54 years old. It had the seat rocking issue, of course. So after watching some youtube videos, and looking into bushings, I ordered some bushings and started fixing the problem. (I am an engineer, and worked my way through school mostly working on cars, so I am a moderately competent shade tree mechanic.)
When I got everything back together, I have two seats that don't move forward or rearward anymore. They don't rock, but don't move either.
I have had both seats out three times, verified everything, and same result: The motor 'clicks' when installed, the lateral drive shafts (motor to transmission) barely start to move, then stop. I have used a tape and a jig to measure the distance for the carriage bolts, they are "the same" distance from the end of the worm gear.
The carriage bolts spin very easily on the worm gear. There is no problem with the carriage bolts.
I can only conjecture two problems:
1. The worm gear does not rotate very easily. It is difficult to turn the worm gear in the fixed bolt fitting. You can turn it by hand, but it is not free spinning by any means. My Dewalt drill will turn it on screw speed (1) with the clutch on setting 1, so it doesn't turn too hard, but it does not spin freely.
2. I did not mark the position where the carriage bolt was when I started. I planned on measuring them carefully so I didn't see any point in marking it. Error on my part, apparently.

Any suggestion? How difficult should it be to turn the worm gear? Any idea how to re-calibrate the whole thing from scratch?

I have checked the measurements, rotational directions of all components (motor, lateral drive shaft, transmission, shaft from transmission to worm gear, rotation of worm gear, direction of carriage bolt on rotating worm gear). Everything appears correct, but the seat just won't move.




yellow2007

I did my seat rock fix 2 months ago. First attempt the seat went back in and would move forward but not back very far. Put the seat on the bench, connected 12volts to it and learned the bushing, even with the new washers would bind up. Removed both rods and chose a middle spot to align them to. Then tried moving the seat again watching the bushings travel and it went all the way back and all the way forward. Bottom line was one of the carriage bolt bushings had become distorted during install.

hyperv6

Fixing these seats is very easy.

I have fixed a few now and once I did get the track off by one turn and it had a slight bind.

Just pull the tracks index them to each other again and you should be fine. 1 to 2 turns off is all it takes. You may think it is the same but it is easy to be off by one.

I have gotten to where I can replace these with out pulling the seat cover anymore and just do the tracks or bracke if needed.

The first seat is the hardest but the more you do the easier it gets.

Vetteman Jack

Moved to C5 Tech.

bngoods

Yellow2007 and hyperv6 thank you for the input. Apparently the shims I bought off eBay (good plastic and clearly Made in USA) are likely too thick. (Per an expert, Dino at CorvetteSalvage, who rebuilds seat tracks, and was very helpful.) I had to really press my shims in place, which "locks" the carriage bolt so tightly the mechanism jams.

So I ordered a set from corvettesalvage.com. He has a set for early (97-02) models and a different set for later models. I ordered the early set for my 98. I think I should be able to get one side of my earlier bushings out without damaging it. I will post an update on how the new set works, and compare the thicknesses of the two sets.

hyperv6

Dino is a great guy!

When I did mine they were tight and I had to tap them in place with a small hammer.

You also need to make sure they stay centered. Just make sure when done there is no play with the bushings and block.

bngoods

Final update ... Dino at Corvette Salvage hit the nail on the head. When I received the Dino's early shims, they were just slightly less thick (I didn't have a micrometer to measure them). But instead of being jammed tight, the carriage nut that rides on the worm gear had just enough slack to be flexible. The carriage nut did not rock back and forth, but it could "adjust" from side to side and up and down. Dino's shims were exactly the width of the carriage, so they did not move.

Apparently the incorrectly sized shims had the carriage nut locked into place without enough slack resulting in the seats being locked up.

So thanks so much to Dino and Corvette Salvage!