How long in primer...

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68-GTS

68-GTS

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Was wondering if there was any "rule of thumb" on how long a car might be left in a primer state .
I was looking at a new project thats in primer... and if i'm correct its been in primer for at least 2 years and out doors for some of it.
Now is that too long and is too late ....or can anything be done to repair any damage that might be done. IE: skim coat the whole car ? or should i just walk away.
 
If its a good primer I think it would be OK.BUT it sat outside a while that would scare me.I would think it would need to be taken down to bare metal and reprimed since its been outside.
 
Type of primer matters. Epoxy primer is the only one I know of that will withstand outdoor conditions.
 
If they laid epoxy over bare metal it would have provided a barrier against moisture. Anything other than that can allow moisture through and you can actually have surface rust form beneath the primer. Fillers will absorb moisture too. Doesn't necessarily mean you need to walk away but there is the potential for problems and you may need to strip it down and re-prime once you know what it or isn't underneath. If they had top coated it after sitting out you'd be none the wiser. You never know.
 
68383GTS said:
If its a good primer I think it would be OK.BUT it sat outside a while that would scare me.I would think it would need to be taken down to bare metal and reprimed since its been outside.
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Agree- if it is a 2k primer, the primer uses a hardener and chemically cures (like concrete does- no matter how much water you put in the concrete will dry). These primers have less chance of absorbing and holding on to water.

If it is rattle can or other super cheap primer, there is a chance there is a high moisture content and the primer will have to be redone. These 1k type primers "dry" when the volatile chemicals escape leaving the solids behind. These solids are vulnerable to changing with the introduction of a new volatile material (ever spilled gas on a lacquer paint job?) even some atmospherically modified H2O.

That all said, if it was crap primer, 2 years outside you would likely see some rust already. Take it down in the most suspect areas (bottom or qtrs etc) if the worst potential area looks ok, just scratch it up and give it a final coat before paint. If you see rust, start over.
 
CudaChris67 said:
That all said, if it was crap primer, 2 years outside you would likely see some rust already.
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this is what I was thinking- I'd probably be more worried if it sat out a month than I would be worried about two years.
I'd think that any problem areas where moisture in/under the primer are going to cause a problem would already be showing up.
 
CudaChris67 said:
Agree- if it is a 2k primer, the primer uses a hardener and chemically cures (like concrete does- no matter how much water you put in the concrete will dry). These primers have less chance of absorbing and holding on to water.

If it is rattle can or other super cheap primer, there is a chance there is a high moisture content and the primer will have to be redone. These 1k type primers "dry" when the volatile chemicals escape leaving the solids behind. These solids are vulnerable to changing with the introduction of a new volatile material (ever spilled gas on a lacquer paint job?) even some atmospherically modified H2O.

That all said, if it was crap primer, 2 years outside you would likely see some rust already. Take it down in the most suspect areas (bottom or qtrs etc) if the worst potential area looks ok, just scratch it up and give it a final coat before paint. If you see rust, start over.
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Just a clarification: 2K means there is a hardener/catalyst used, but does not mean it is an epoxy. Not all 2K primers are waterproof. Epoxy is a 2K (2 part) primer that is waterproof.
 
Yea... if i had to bet .. i'd say it was a rattle can by the looks of it.
It has that surface rust showing through in some of the primed areas.
It was outside under a carport area so no direct rain and as i said i'm unsure of how long it was subjected to the elements /humidity.But if a body shop ( being professionals ) were to do the paint as this would be the plan, what are the chances of rust pitting returning somewhere down the road.
 
They would strip it bare,then fix what's needed.They apply their own preferred primer,to work with their in house paint brand.Unless you do a Maaco,Eral Schieb,or something similar.They do this to ensure final product quality.
 
In your area I would be worried. What is that primer hiding? Be wise to strip it and reprime and check for areas that might be of problem. It could be hiding alot of work ahead. Maybe the sellers has photos of before it was primed?
 
It also depends on the price of the car.
You can reverse a lot of problems if it's just surface rust that's not hiding bad body work under that primer......
Hope for the best and expect the worst.
Maybe have your body man go look at it and see what he says, after all, he's the one that would be charging you to reverse whatever is wrong.
 
Good info thx.... Its not really hiding anything it still has the usual holes needing repairs IE rear quarters and such, but the primed areas are were some striping was sanded off and of course they carried on a little further just to make it look better haha .. Its quite plain to see no filler has been added anywhere yet they didn't get that far yet ( bonus ). BTW the car is completely apart pretty hard to hide anything i can see inside most every panel which at least to me is another bonus.
 
i would just take it all down and shoot it with a good epoxy primer and never look back or worry about it
 
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