1981 Bumper Extension Adjustment (up/down)??
Thread Starter
Burning Brakes
Joined: Feb 2016
Posts: 874
Likes: 115
From: Round Hill Virginia
1981 Bumper Extension Adjustment (up/down)??
Question: Is there up or down adjustment of the bumper extension on the 81? The glass has become separated from the cross-bar making the front center of the hood look like it's diving down when in reality I think the nose is pushed up a bit. I can push the glass down, but it takes some force. It looks like the previous own may have hit a parking curb a little too hard - the bottom of the support plate was bent a bit. I straightened it out but I think the whole assembly (though looks straight and measures out) needs to come down. Another old thread someone said that you can just loosen up the four bolts and it will move up and down. Before I start digging I thought I'd ask the forum?! I've attached a picture of the part (picture from BigCity Corvettes). Also, the rod does not seem to do anything. I'd be curious if anyone has any pictures of that area - the rod as a slot and I'd like to know where that adjustment is on a nose that's straight. Thanks!!!
Race Director
Joined: Apr 2009
Posts: 19,294
Likes: 2,754
From: Charlotte NC
The fiberglass extensions that go through the inner skirts and bolt to the fiberglass impact bar and honeycomb do have some adjustment...but they work somewhat in conjunction with the main metal support you posted a photo of.
You are aware...if my memory serves me correctly...there is a rubber bushing that goes between the part you have shown and the metal retainer that is pop riveted and glued to the inside front edge of the top hood surround.
DUB
You are aware...if my memory serves me correctly...there is a rubber bushing that goes between the part you have shown and the metal retainer that is pop riveted and glued to the inside front edge of the top hood surround.
DUB
Thread Starter
Burning Brakes
Joined: Feb 2016
Posts: 874
Likes: 115
From: Round Hill Virginia
There is a bolt with a rubber bushing. The fiberglass (was) bonded to the steel cross bar and thats bolted to the bumper extension (pictured) - the bolt you mention. I'm wondering if that whole assembly moves? Its like the nose is pushed up a bit. When i push the fiberglass down to meet the hood it doesn't 'want' to be there. It just seems like the nose needs to come down and out a smidge. I need to re-glue the fiberglass back to the brace but i don't want to do it until it doesn't feel like I'm 'fighting' it. Hopefully this makes sense?
Race Director
Joined: Apr 2009
Posts: 19,294
Likes: 2,754
From: Charlotte NC
There is a bolt with a rubber bushing.
Good so far.
The fiberglass (was) bonded to the steel cross bar and thats bolted to the bumper extension (pictured) - the bolt you mention.
And it was also pop riveted as well....CORRECT???
I'm wondering if that whole assembly moves?
What do you mean by 'whole assembly'????
Its like the nose is pushed up a bit. When i push the fiberglass down to meet the hood it doesn't 'want' to be there. It just seems like the nose needs to come down and out a smidge.
THEN..the part you posted a photo of can be moved...but not knowing if you have moved it already it is hard to say. You did not say.
I do not know what you are doing and if you are using correct SMC panels or aftermarket hand laid fiberglass parts...which make a difference....and this is where you are loosing me.
I need to re-glue the fiberglass back to the brace but i don't want to do it until it doesn't feel like I'm 'fighting' it. Hopefully this makes sense?
Good so far.
The fiberglass (was) bonded to the steel cross bar and thats bolted to the bumper extension (pictured) - the bolt you mention.
And it was also pop riveted as well....CORRECT???
I'm wondering if that whole assembly moves?
What do you mean by 'whole assembly'????
Its like the nose is pushed up a bit. When i push the fiberglass down to meet the hood it doesn't 'want' to be there. It just seems like the nose needs to come down and out a smidge.
THEN..the part you posted a photo of can be moved...but not knowing if you have moved it already it is hard to say. You did not say.
I do not know what you are doing and if you are using correct SMC panels or aftermarket hand laid fiberglass parts...which make a difference....and this is where you are loosing me.
I need to re-glue the fiberglass back to the brace but i don't want to do it until it doesn't feel like I'm 'fighting' it. Hopefully this makes sense?
DUB
Last edited by DUB; Oct 20, 2016 at 06:56 PM.
Thread Starter
Burning Brakes
Joined: Feb 2016
Posts: 874
Likes: 115
From: Round Hill Virginia
Sorry for being such a noob! You're right, there are two braces. The one at the very front and in front of the headlights does have rivets and bolts for the poly bumper. Those are the only rivets I can see anyway. The second brace is as you said, behind the headlights. The epoxy is no longer holding down the hood surround - between the headlights and hood itself. The frame extension that is pictured is what I guess I'm referring to as the "assembly". It looks like there are 8 bolts holding that to the frame - two for the extension itself and two more that hold the two side extensions. The side extensions seems to be for nothing more than to support the front/side body. So, I'm thinking or wondering if anyone has loosened those 8 bolts (that fasten the extension to the frame) and was able to move the nose of the car up or down. I wouldn't expect a lot, but I think that might be what needs to happen.
I think the nose was pushed up from a previous owner hitting a parking curb. So, one of three things needs to happen...four I guess. 1. adjust if it can be, 2. epoxy and clamp the crap out of it and force it to stay in place, 3. replace the extension as the current one may be bent?, and 4. beat it ( the extension) with a bar and sledge to bend back down - of course NOT on the body but inside were that front plate is... It's the nose just under the emblem that seemingly needs to be pushed down a smidge. So it seems anyway...
There's no mention but for one post that for whatever reason I can't seem to find at the moment. Old post so I didn't bother. At any rate, I'll see if I can make a copy of the AIM page and hopefully do a better job of articulating what I'm asking. I do better with pictures any way.
I'll also try and loosen those 8 bolts up and see what happens.
Thanks for the replies on this. It helps!
I think the nose was pushed up from a previous owner hitting a parking curb. So, one of three things needs to happen...four I guess. 1. adjust if it can be, 2. epoxy and clamp the crap out of it and force it to stay in place, 3. replace the extension as the current one may be bent?, and 4. beat it ( the extension) with a bar and sledge to bend back down - of course NOT on the body but inside were that front plate is... It's the nose just under the emblem that seemingly needs to be pushed down a smidge. So it seems anyway...
There's no mention but for one post that for whatever reason I can't seem to find at the moment. Old post so I didn't bother. At any rate, I'll see if I can make a copy of the AIM page and hopefully do a better job of articulating what I'm asking. I do better with pictures any way.
I'll also try and loosen those 8 bolts up and see what happens.Thanks for the replies on this. It helps!
Race Director
Joined: Apr 2009
Posts: 19,294
Likes: 2,754
From: Charlotte NC
Sorry for being such a noob!
It is OK.
You're right, there are two braces. The one at the very front and in front of the headlights does have rivets and bolts for the poly bumper. Those are the only rivets I can see anyway. The second brace is as you said, behind the headlights. The epoxy is no longer holding down the hood surround - between the headlights and hood itself.
Correct.
The frame extension that is pictured is what I guess I'm referring to as the "assembly". It looks like there are 8 bolts holding that to the frame - two for the extension itself and two more that hold the two side extensions.
Correct.
The side extensions seems to be for nothing more than to support the front/side body.
NO...the fiberglass side extensions that bolt to the frame ALSO bolt to the ends of your fiberglass impact bar with honeycomb plastic. These extensions have nothing to do with holding any part of the front clip. they are strictly for impact.
So, I'm thinking or wondering if anyone has loosened those 8 bolts (that fasten the extension to the frame) and was able to move the nose of the car up or down. I wouldn't expect a lot, but I think that might be what needs to happen.
YES you can do that BUT it all depends on variables. There is only so much given movement in the parts that attach to the ends of your frame rails.
I think the nose was pushed up from a previous owner hitting a parking curb. So, one of three things needs to happen...four I guess. 1. adjust if it can be, 2. epoxy and clamp the crap out of it and force it to stay in place, 3. replace the extension as the current one may be bent?, and 4. beat it ( the extension) with a bar and sledge to bend back down - of course NOT on the body but inside were that front plate is... It's the nose just under the emblem that seemingly needs to be pushed down a smidge. So it seems anyway...
There's no mention but for one post that for whatever reason I can't seem to find at the moment. Old post so I didn't bother. At any rate, I'll see if I can make a copy of the AIM page and hopefully do a better job of articulating what I'm asking. I do better with pictures any way. I'll also try and loosen those 8 bolts up and see what happens.
Thanks for the replies on this. It helps!
It is OK.
You're right, there are two braces. The one at the very front and in front of the headlights does have rivets and bolts for the poly bumper. Those are the only rivets I can see anyway. The second brace is as you said, behind the headlights. The epoxy is no longer holding down the hood surround - between the headlights and hood itself.
Correct.
The frame extension that is pictured is what I guess I'm referring to as the "assembly". It looks like there are 8 bolts holding that to the frame - two for the extension itself and two more that hold the two side extensions.
Correct.
The side extensions seems to be for nothing more than to support the front/side body.
NO...the fiberglass side extensions that bolt to the frame ALSO bolt to the ends of your fiberglass impact bar with honeycomb plastic. These extensions have nothing to do with holding any part of the front clip. they are strictly for impact.
So, I'm thinking or wondering if anyone has loosened those 8 bolts (that fasten the extension to the frame) and was able to move the nose of the car up or down. I wouldn't expect a lot, but I think that might be what needs to happen.
YES you can do that BUT it all depends on variables. There is only so much given movement in the parts that attach to the ends of your frame rails.
I think the nose was pushed up from a previous owner hitting a parking curb. So, one of three things needs to happen...four I guess. 1. adjust if it can be, 2. epoxy and clamp the crap out of it and force it to stay in place, 3. replace the extension as the current one may be bent?, and 4. beat it ( the extension) with a bar and sledge to bend back down - of course NOT on the body but inside were that front plate is... It's the nose just under the emblem that seemingly needs to be pushed down a smidge. So it seems anyway...
There's no mention but for one post that for whatever reason I can't seem to find at the moment. Old post so I didn't bother. At any rate, I'll see if I can make a copy of the AIM page and hopefully do a better job of articulating what I'm asking. I do better with pictures any way.
I'll also try and loosen those 8 bolts up and see what happens.Thanks for the replies on this. It helps!
I can say you need to make sure the car is ON the ground and NOT on jack stands....but I am still lost in what you are doing.
Good clear photos help out in scenarios like this.
DUB
Race Director
Joined: Apr 2009
Posts: 19,294
Likes: 2,754
From: Charlotte NC
SO...I have to guess here.
I am guessing that you are trying to bond the top hood surround panel back to the metal support BEHIND the headlights so the top hood surround is flush with the hood.
Post a photo WITHOUT your son pressing on the top hood surround. I need to see what you are trying to fix. Take that photo from the same angle as the one you did with your son holding it down.
I will wait for your reply...because I see something that is not good...but can be fixed.
DUB
I am guessing that you are trying to bond the top hood surround panel back to the metal support BEHIND the headlights so the top hood surround is flush with the hood.
Post a photo WITHOUT your son pressing on the top hood surround. I need to see what you are trying to fix. Take that photo from the same angle as the one you did with your son holding it down.
I will wait for your reply...because I see something that is not good...but can be fixed.
DUB
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yes! That's exactly what I'm trying to do is bond that back down but it does not "want" to be there. Hopefully this picture helps?
Race Director
Joined: Apr 2009
Posts: 19,294
Likes: 2,754
From: Charlotte NC
YES...that photo is PERFECT!
Now knowing what you are wanting to do. I honestly feel it has nothing to do with the part you posted in a photo initially.
This delamination is common.
You do understand that the front bumper and headlight assemblies (completed) MUST come out in order to fix this????
I can see why it delaminated. The condition of the support brace that is behind the headlights is severely rusted. And I can see what also looks like a moldy type residue staining to the underside of the top hood surround in the second photo of POST #7. I ahve seen this effect when a car is covered outside or stored in an area with a lot of moisture and minimal air flow.
NO WORRIES. I have done many of these ...so if you want help...just let me know. If you do...you might want to PM me so I can get you my shop phone number and we can talk instead of me typing out the procedure. Unless you find a written procedure somewhere and use it...whatever works for you.
DUB
Now knowing what you are wanting to do. I honestly feel it has nothing to do with the part you posted in a photo initially.
This delamination is common.
You do understand that the front bumper and headlight assemblies (completed) MUST come out in order to fix this????
I can see why it delaminated. The condition of the support brace that is behind the headlights is severely rusted. And I can see what also looks like a moldy type residue staining to the underside of the top hood surround in the second photo of POST #7. I ahve seen this effect when a car is covered outside or stored in an area with a lot of moisture and minimal air flow.
NO WORRIES. I have done many of these ...so if you want help...just let me know. If you do...you might want to PM me so I can get you my shop phone number and we can talk instead of me typing out the procedure. Unless you find a written procedure somewhere and use it...whatever works for you.
DUB
Race Director
Joined: Apr 2009
Posts: 19,294
Likes: 2,754
From: Charlotte NC
YEP...I have seen this. Nothing about any of these photos you posted here scare me in the least in POSTS # 9 & 11.. I would put my money on the FACT that the impact bar is causing this. This is common.
And YES...to confirm what you are experiencing...it will have some tension on it when you try to press down on the panel.
DUB
And YES...to confirm what you are experiencing...it will have some tension on it when you try to press down on the panel.
DUB
Thread Starter
Burning Brakes
Joined: Feb 2016
Posts: 874
Likes: 115
From: Round Hill Virginia
Perfect! It's in my garage now as I've been going through it and will stay that way for as long as I own it. I'm the third owner, and it was garaged and well maintained, then the second owner (from whom I bought it) left it sitting outside. Good catch!! #7 does look wet, but most of that is because it was dowsed with a good bit of PB blaster so I could loosen the center mount. the support braces are rust though. not pitted or anything like that. Hopefully salvageable. I'll send you a PM so we can get in touch! Again, thanks for talking through this. I wasn't really sure what to do. I really enjoy working on this car and don't want to take to any shop unless I have too - though taking it to you in NC sounds tempting! I lived in Denver on Norman for a bit. Beautiful there. As for the car...it's my therapy!
Race Director
Joined: Apr 2009
Posts: 19,294
Likes: 2,754
From: Charlotte NC
I can see the wet area where the PB Blaster got onto the panel. I am looking at the dark gray/ blackish staining of the panel....where PB blaster did not get onto it. That is what I was commenting on.
You have to be CAREFUL with that PB blaster or anything you spray that gets on the backside of a raw panel. If that product lingers on the panel...it can soak into the SMC.
The sun can suck that contaminant into the SMC and cause for bubbles in the paint.
It is not going to happen right away. And the amount that is on there may do nothing at all. But it is just WISE to NOT spray anything that can get on a the backside of a panel. If it does occur...it should be wiped or cleaned off. If this were metal bodied car...it would not matter...but your body panels are not like metal. SMC/fibergass CAN absorb stuff in them from the underside if it is allowed to stay on there. Kinda like oil form an A/C compressor spraying oil on the underside of your hood. it can cause the paint to bubble on the outside of the hood..
None of this has anything to do with your hood surround delamination..I thoguth I would mention it.
DUB
You have to be CAREFUL with that PB blaster or anything you spray that gets on the backside of a raw panel. If that product lingers on the panel...it can soak into the SMC.
The sun can suck that contaminant into the SMC and cause for bubbles in the paint.
It is not going to happen right away. And the amount that is on there may do nothing at all. But it is just WISE to NOT spray anything that can get on a the backside of a panel. If it does occur...it should be wiped or cleaned off. If this were metal bodied car...it would not matter...but your body panels are not like metal. SMC/fibergass CAN absorb stuff in them from the underside if it is allowed to stay on there. Kinda like oil form an A/C compressor spraying oil on the underside of your hood. it can cause the paint to bubble on the outside of the hood..
None of this has anything to do with your hood surround delamination..I thoguth I would mention it.
DUB