Lifting a C-4

[Mart]

OK, Correct me if I'm way off base here, but this whole frame flex deal has me :ugh


So here goes, The whole vehicle sits on four points (the wheels), If I move those four points towards the center a foot or so the should be less room for flex, if I move them out towards the front and rear then the frame will flex more.

So when cornering the car must go through more flex than when it sits static on a lift or jackstands due to the other forces applied, not just the down force applied from the weight of the vehicle which is distributed accross four points.

In conclusion just how is having the top up or unlatched on your vert going to be affected, do you not corner agressivly with the top up?

And where the jackstands are placed on the front end is right below the bottom of the winshield and the hood, therfore there is no flex from there forward that would cause the hood to bind.

I don't get it....
Somebody splain this to me.. :W

Mart

 

[rwpeders]

You have good questions and I don't have the answers. I am only reporting what they have done and said is necessary to avoid damage when lifting the car. The service manual doesn't say anything about undoing the top, releasing the hood latch or opening the doors or the many other things that people say are necessary. Perhaps it was necessary "once upon a time" with older models and has just carried forward. However, I had a '62 roadster and a '73 convertible and never saw any of this then.

So maybe this is just a corvette urban legend with no real basis in fact.

 

[Mart]

This sounds like a job for "MYTHBUSTERS".... Adam, Jamie....

Oh well, just rambling....blah blah blah.

 

[ZRXMAX]

This sounds like a job for "MYTHBUSTERS".... Adam, Jamie....

Oh well, just rambling....blah blah blah.

I understand your confusion and frustration... and mythbusters ? at least you still have a sense of humor !

Believe it or not... and to broaden the myth aspect... I have pictures on my old 35th Anniversary at Americas tire store sitting on a belly pan lift for a tire change... What lifting points were they using there? I assume it was sitting on the flange part of the frame.. otherwise it must have been sitting on the fiberglass belly...

One time I had a shop put a floor jack right through the footwell of my 84... They had a body shop fix it...

 

[Mart]

Trying to hold on tight to the sense of humour, especially with what I am going through right now with my rear hubs, and the previous ID10T welded the studs into the hub, replacing the hubs is going to cost me $600.00 bucks, or I try to grind off the head and see if they come out so I can put new studs in. He put in longer studs so he could use wheel spacers, but the 88 wheels are hub centric so they never go on quite right and it feels like they are out of balance.

whew, I'm out of breath after that one.

If this is'nt proof that once you own a corvette you will do anything to play with and enjoy it.

Don't mind my rant.
Mart

 

[WhalePirot]

Don't mind my rant.

We all get our turn 'in the barrel' and it does end, with patience and some expert help. Ken and I have been there, and rrubel has, too. Some is self induced.

 

[ZRXMAX]

Don't mind my rant.
Mart[/QUOTE]
We don't mind... its cathardic...

I just changed both of my rear wheel bearings last summer... I am trying to picture what the guy welded... I take it he welded the end of the bolt that hangs just outside the wheel bearng flange... Just going off your description and my memory... I would grind the end of the bolts flat and then some... That will get rid of a lot of the welded area, but some may still remain depending on how much penetration he got when he had that brain cramp... Since the wheel bearings are going in the trash anyway... I would just grind till the flange was very thin... I know that is a lot of grinding...

If that does not do it after considerable grinding... The do the most precision center punch job possible on each bolt... Then... starting with a small drill do your best to drill right down the middle of the bolt... but not all the way through... you will need to measure and mark your bits... as you size upward with bigger drill bits you need to measure how deep you can go without getting into anything that needs to stay untouched... At some point you should be able to separate the wheel bearing from the knuckle... Go slow and be patient... a good set of sharp cobalt bits will make it a little bit easier...

Perhaps their is a better way to do it... Hopefully somebody has a simpler answer for your dilema...

One time I had a Beretta V6 and somebody had JB welded the middle spark plug on the firewall side of the motor... One day with 50+ miles left to drive home it blew out... Yeah... I had a word for the idiot that did that...
I could only see the plug hole with a mirror... I fixed it without pulling the head and it was never a problem again... I was kind of lucky on that one...

Good luck with yours...
Ted

 

[G Winter]

We all get our turn 'in the barrel' and it does end, with patience and some expert help. Ken and I have been there, and rrubel has, too. Some is self induced.

Self induced.. boy do I hear you on that one.

 

[Mart]

First off, I feel horible for hijacking blu by U's thread, I will make it up to ya.

Here is a pic of the front hub. And ZRXMAX you are right about the welds.

Now to make it up to you.

Is the Red area where everybody is talking about putting the jackstand.

And no the car is not resting on that stand, it's on a jack.

 

[Mart]

And yeah I know the car is filthy, but it gets driven, over 215,000 km.

wait till I get this mess cleaned up I'll post before and after pics.

Thanks
Mart

 

[ZRXMAX]

First off, I feel horible for hijacking blu by U's thread, I will make it up to ya.

Here is a pic of the front hub. And ZRXMAX you are right about the welds.

Now to make it up to you.

Is the Red area where everybody is talking about putting the jackstand.

And no the car is not resting on that stand, it's on a jack.

I see it is a front wheel bearing, correct ? Did you remove that wheel bearing in your picture ?

In the jack picture you look just fine... I use a short 2x4 to span the area you have marked with the box... I also use a 2x4 on top of the floor jack cradle to lift on the frame rail at the rear area of the door... that leaves me plenty of room to get the jack stands in...

 

[Mart]

Yup, replaced both front last year now I am doing the rears, maybe. I just got the the rearend off the ground and can feel play when at 12-6 on the wheel, I was thinking about just removing the studs and putting them back, but with the wheel movement I'm not sure what to do.

Opinions?

Mart

 

[ZRXMAX]

Yup, replaced both front last year now I am doing the rears, maybe. I just got the the rearend off the ground and can feel play when at 12-6 on the wheel, I was thinking about just removing the studs and putting them back, but with the wheel movement I'm not sure what to do.

Opinions?

Mart

You need to determine if the bearing have worn out... A dial indicator on the rotor is the most accurate way to tell... Some play is there even when new... a dial indicator will give you a better idea... I don't know the spec... or the play tolerance... you need a book to tell you that... I find that just grabbing the wheel by hand will give you an idea of how loose it has become... compare it to other wheels... If you get the whole car up you will likely be able to feel the difference between the wheels... The one that feels the tightest , assuming it is a good one, will be the benchmark for the rest... If your not hearing a bearing going bad yet, you probably have some miles left before a change is needed...
If you change a few and find that is was premature... you have spares for any road trips where a bearing could spoil your day... Nothing worse than taking a long trip, having a part fail, and not being able to find another part...

 

[donjuan5858]

Lifting c-4's

I have been told by the original owner of my c-4 that the most common mistake made by shops when lifting, is the top is bolted down too tight on targa tops, and they will crack. Hence most glass tops become cracked for just that reason.
I suggest that when ever your going to put your vet on a jack or up on a rack yourself or in a shop, loosen all the screws on your targa, and inform the shop.