70 Seats & Seat Belts

[Juliet P.]

I removed the seats & seatbelts from the car today. I finally figured out why one seat was sorta cockeyed... the frame is cracked on the bottom where the rubber bumper thing is screwed into the (formerly) welded nut on the underside. Has anyone successfully welded one of these? They seem like relatively thin metal. Any tips / suggestions?

Only one side of the rear seat bolt downs was bolted in my car, even though both sides of the track had tabs with holes. I pulled up the carpet (which is not original) thinking there were bolt holes & bubba the carpet layer just was lazy.... but couldn't find any. Later I read in the JM that this is the way it's supposed to be. Oh well, I found a 1963 penny while I was under the carpet. This the JM didn't cover: Do original rear '70 seats have an oversized oval hole on the right rear tab and a smaller circular one on the left. Is this correct for 1970 seats?

What size bolt do I need to attach the shoulder belt in the rear? I'm putting camaro REAR belts (yes, incorrect, but it's GM and safer than my lousy imported incorrect lap belts). I felt & found the factory hole in the rear, but havent' cut the carpet yet... even if I do I'm awful at judging sizes without test fitting. My rear carpet is original so I'm kinda nervous about cutting it. I might just make a slit so I can stitch it later instead of nibbling out a hole. I noticed that the bolts I got with my camaro belts are smaller diameter than the front 2 lap belt bolts. Are the rear bolt holes the same size as the front? Anyone know of a source for these ala carte? I don't want to spend $50 on 2 complete seatbelt hardware kits with extra unneeded stuff. Since these aren't stock anyways, I'd rather just get whatever will fit at the hardware store and plate it with that black stuff. Anyone know what size I should buy?

There are 2 metal tags attached to the underside of the seat in the spring things, with numbers stamped into them. Anyone know how to decode / interpret these? I'm trying to figure out if the seat frames are original. I'm pretty sure the upholstery has been replaced, but I don't know about the seats themselves. They do look pretty old. ;) I took a bunch of pictures... hopefully I'll get them developed tomorrow and online in another day or so.

Thanks for any info you can offer. :D ~Juliet


Juliet's 1970 Corvette

[Terry M.]

Re: 70 Seats & Seat Belts

Juliet,

I'll try to get to the garage today and see about holes in the tracks. Never had the shoulder belt hold down bolts out, so don't know the size. My memory of the fronts is that they are not common hardware store shapes or sizes. Shoulder under the bolt head comes to mind. Might have to raid automotive recycling yard for bolts for shoulder harness. There is a chance (slim) that parts book might show shoulder belt bolt dimensions. Sometimes they do that for special bolts. I'll look later today too.

I have had success welding seat frames on other GM products, but never tried Corvette. Have had to use "patches" to reinforce some broken frames, depending on location and cause of crack. It does take some skill with a welder - I used MIG, but a skilled gas welder might work as well. MIG was at hand.

I remember metal tag, but since is where the sun don't shine, never spent time to try to decode it.

Upholstery, if original, will have date code on reverse side of material (at least on vinyl - not sure about this on dead cow upholstery.).

Later.

Terry

[Wayne M.]

Re: 70 Seats & Seat Belts

Juliet -- Re metal tags under seats (bent around springs): Since Terry M. is not certain about the decoding of these, let me submit what I have found in my '65s, and MAYBE it will be similar. What I thought was one tag was actually two (folded together); one with the part # of the seat (matches AIM for black vinyl), and the other was the day and month of assembly. Same on both seats.

[Joe L.]

Re: 70 Seats & Seat Belts

Juliet-----

A few comments regarding the seats:

1) Recently, an aluminum reinforcement "plate" has come onto the Corvette market of which the specific purpose is to reinforce the rear of early C3 seat bottom frames. This plate is available from Corvette Central and, probably, other vendors as well. I'd weld the frame as Terry suggested and add the plate. They're not very expensive and I doubt that anyone will ever notice it since Corvette seats are not configured in such a way that folks (or "judges")can get underneath and crawl around too much.

2) In a post elsewhere you asked about the corect finish of the seat tracks. 1968-71 Corvette seat tracks are finished in a dark gray or black phosphate type finish. This is the finish on my original 1969 seat tracks and also the finish on an NOS car set of these tracks that I recently added to my collection.

[Jon W.]

Re: 70 Shoulder belt bolts

Juliet, It's been a couple years since I cleaned up and made operational the shoulder belts /retractors in my '70 coupe. I don't know if convertibles used the same set-up, but suspect they do. (Don't have access to my references at the moment) My retactors were bolted intom the rear compartment area with bolts that I recall being identical/very similar to the bolts used to mount the inboard and outboard lap belts. They were domed hex-head bolts with shoulder on them. I'm sure the lap belt bolts would work.

[Jack H.]

Re: 70 Seats & Seat Belts

(1) Seats can be saved via weld repairs. Best to have 'skins'

and foam off....

(2) Problem with broken welds flows (my opinion) from owners

not having/reading/following owners manual. Here's the

'boogie':

(a) Dude decides he doesn't like the angle of the seat.

(b) Dude 'discovers' the factory conveniently provided

seat back cant adjusters (screw-in upper bumpers),

even though this 'feature' is not described anywhere.

(c) Dude 'adjusts' the screw-in bumpers to make seat back

cant be more upright (despite the fact each car shipped

with a chew-string bag of seat back shims designed for

this purpose that were 'lost'.....).

(d) After dude sits in seat and drives for a while with

it in its 'improved adjustment' position, the rubber

bumper shafts bend due to excessive moment arm stress.

(e) Now, all Hell starts to break loose as upper and lower

supports fail to mesh properly, excessive strain begins

to take a toll on seat back pivot bushing/screw and,

in the end, the captive weld nuts in the seat back

and seat cushion frame snap loose as well as the

spot welds holding the frame components together.

FLASH, there's a REAL PRETTY '70 (base, coupe, A/C, AT, D-month) being parted out down the road here in Denver. Red with tan interior. Many parts from steering wheel back available to he/she who makes contact with parter asking for them, including seats, rear compartment items, seat belts/shoulder harness, Etc. Car even has the original Cal smog system intact, including 502 carb with choke and heat shield....

[Terry M.]

Re: 70 Seats & Seat Belts

Juliet,

Sorry for the delay - work still pays the bills (well almost).

Seat tracks: Yes the right hand (passenger side) bolt hole on all 4 tracks is elongated. The right hand track on each seat is bolted through this hole. Left hand track on each seat is bolted through the round hole. Jack has the seat track finish correct.

Broken back: I was not aware of the reinforcement that Joe mentioned, but if it is aluminum and the seat is not then you will have to bolt/screw it in place, but any reinforcement is good - go fo it. Of course Jack is right you have to have ALL the combustibles off the seat frames when welding.

Jack's scenario may be correct, but I have welded seats by Cadillac and Chevrolet/GMC truck. Also participated in similar repairs of 94 Caprice 9C1 (police car) - I am sure the truck and Caprice were a case of dudes consuming too many doughnuts - never met the owner of the Cadillac. Short of that is it can happen to any seat - no big deal to weld and reinforce to make stronger than new. Hardest part is to strip foam and upholstery, but you were doing that anyway - right? BTW: The Cadillac was a early '90s aluminum tub kind of frame. It was a real challenge - had to brush up on TIG welding for that one. I would NEVER do that kind of thing again - favor for a friend deal.

Shoulder belt bolt - Can not see bolt due to plastic cover over harness reel. Parts book shows bolt 3956042, but gives no size - Parts book also shows different number bolt for lap belts, but they go through a different metal piece than the reel. My best guess it the bolts are 7/16-20 thread. Try the hardware store for one of those 3/4 or 1 inch long. Only get one to try. Try in the hole to establish diameter and threat pitch as correct. Since you are using Camaro parts the original length bolt Corvette bolt may/may not work anyway. Maybe someone here has their shoulder harness out and can give bolt size.

Once you have established diameter and thread pitch and needed length, go to really good bolt supplier - there are some around me that cater to air plane folks, or a mill supply shop that caters to industry. Get 2 bolts in the size you need in grade 8 - 6 radial lines on the bolt head. Use a little anti-seize so you can get them out if you ever want, and drive safely. NOTE: Use grade 8 for strength - this is no place to cut corners.

Terry

[Patrick H.]

How come?

Jack,

So if it is real nice, why is he parting the 70 out???

Patrick

[Jack H.]

Re: How come?

This is Rocky Mountain country where salt on the road rust buckets don't exist. Supply of 'recent' vintage Corvettes is relatively robust -- a relatively untouched '71 LS-5 roadster (green with tan leather interior) recently sold for a whooping $6K and new owner is merrily 'chopping' fenders to make big time flares, ripping out stock instrument panel, Etc. Kinda makes you cry when you realize the sweat others around the country generate to even find an 'untouched' car of this era to start their restorations with....

NOOWW, when you start talking straight axle or mid-year cars, the story changes big time out here. Few bargains to be had -- just like the rest of the world.

In the case of the '70 that's being parted, it was smacked in the rear end causing major fiberglass loss (one corner of gas tank is dented and punctured), the LH front fender is history around and into the nose (but hood and engine compartment is intact). Car had standard insurance and NO HISTORY of historical significance (another reason to have baby judged every so often, guys!), so the insurance company totaled 'er out.

Engine compartment is about as stock as you can get and interior that's there could almost Bowtie. Current owner is a Corvette shop that knows what NCRS/Bloomington is all about, but doesn't have a high opinion of restoration/preservation. Knows, he can divide and conquer for a healthy profit on a piece by piece arrangement. Heck, I grabbed the gas cap which is about as pretty and clean as they come for a whooping $5....

What was the Tony Curtis line from Operation Petticoat? The base is under air attack, guys are running every which way for cover, and Carrey Grant stops Tony Curtis who's leaving the ship dressed in black face to ask what's up.... Curtis turns, grins and says, "In confusion, there is profit!"

[Juliet P.]

Re: 70 Seats & Seat Belts

Thanks everyone for the info. The rear retractor bolts are 1/2" -13 with no shoulder. It is the same size bolt hole in the rear as in the front, however the bolt is one threaded all the way up to hold the retracter fixed. I was able to find a set of Grade 8 bolts at Pep Boys. :) The bolts on either side of the seats are the shoulder type because the belts need to pivot on the bolt. The rears do not.

We have a mig welder and I had my husband take a look at the seat. Tomorrow he is going to try to weld it. I don't trust myself with a welder yet. ;) I don't want to un-upholster the entire seat so I'm going to cover it completely with foil and put a damp rag on top of that. My husband has used this technique before when welding things where splattering might cause damage and it has worked well. I'll post our success / failure tomorrow.

For now I just wire brushed the rusted parts of the seat "feet" and painted them black. When I get to my full restoration the paint can be easily removed. I didn't want to do too much with the seats other than repair work right now. The list of higher priority items is way to long to start tearing the seats apart right now. I did want to address the rust & cracked frame however.

Hope I didn't miss anything... it's late! ~Juliet




Juliet's 1970 Corvette

[Juliet P.]

Just a thought...

I've had several suggestions to completely overhaul the seats and do it "right." I couldn't agree more! I will do that, however, the problem is all in the timing....

I just don't have time to get it done before I have the car judged in 15 days (YIKES!!) at the Glen Burnie regional meet. I'm entering it for my "pre restoration" benchmark, so I don't want to restore much at this point. I need to find out what I'm starting with first! After the meet I'll make a nice priority list of items to restore properly. The goal right now is to get it all back together! The spare assy is out (for glass repair), the bumpers are off (for glass repair (completed BTW) from our winter mishap with my husbands suburban), the interior is pulled to swap out the seatbelts & repair the seat, the driver window assy is back together but the panels are still of (hunting down bolts), the pass side is ripped apart for overhaul (broken weld on bracket).... And my correct & dated carb just arrived yesterd (got it for a mere $150 on eBay!)... so I have a rebuild to do on that (new kit with needles, jets ets should be here today), so I can address the incorrect choke rod (god awful cold performance on the beast) and the heavily hacked in vac adv lines, wired heat stove riser, wrong choke rod & some performance issues etc...

I'll agree, the seats need to be completely ripped apart and redone... it's just not going to hapeen until AFTER the March 18 meet though! Yikes, typing all this reminds me that I'd better put more penetrating oil on those heat stove crossover bolts if I'm ever going to get them out this weekend.... I've been oiling them for a week now. :)

Thanks for the input. I know that a complete overhaul is the right answer... I'll just have to wait a while to tackle that project. Plus I'm just dying to drive the car... between snow & mechanical stuff other than one afternoon it's been Jan since I've driven it! ...and driving is kinda tough to do without any seats! LOL! I just didn't want you to think that I wasn't concerned with doing a quality restoration here... I am, it's just how long (years!) it takes me to get to that point! :) ~Juliet


Juliet's 1970 Corvette

[Terry M.]

Re: Just a thought...

Juliet,

Glad to see you got the carb. Looks like you have a long list of projects to get to before the meet.

Good luck.