How Long Can I Leave a Car in Primer? Primer/Filler vs. Weather

I fixed all the dents on a old CJ7 primed it with black lacguer prime and after wet sanding with 320 I thought it looked good and never painted and it was fine for the next 2 years I had it.

Well, sorry to say this but I'm getting rust bleed through after spraying 3 coats of Speedcoat Lacquer primer surfacer using the Harbor Freight purple gun. I sprayed it onto bare shiny metal and bondo 3 months ago and rust is coming through the bare metal areas. The metal and filler was block sanded with 120 grit and wiped with Eastwood Pre Paint Prep before priming. The vehicle is outside under a carport. Did I do something wrong? I'm in damp NW Washington state, so maybe that's a factor. What should I do before painting? Thanks.

My whole foxbody has had primer for 2 years now... starting to turn moldy color ...

Hi Jerry, i have been working on a classic car of mine for a few months now. I have taken the car back down to bare metal and have done the welding and filling repairs. The car has sat in bare metal now for around three months, can i just prime over this or do i need to treat/clean the metal first to make sure there is no surface rust? Thank you Sam.

Whats the point of spray bond black?

I have surface on roof of car whats a good spray can primer to use will be left out fir awhile till i save up for paint

That answers the question

Excellent info. Thanks!

Great video. Just curious what brand primer did you use? Thanks in advance.

the most realistic channel out there. thank you Sir

Forever if its inside the garage

Love your videos!!
My car has been epoxy primed with Eastwood 2K roll-on primer and their 2K aero-spray. I have a small section that I needed to address and now I have some bare metal. Can I shoot that small section with some Krylon primer (cheaper then Eastwood) to protect it until I get to shoot my urethane primer or do I need to stick with the Eastwood 2K?

Do you have any videos of repairing rust on the bottom of doors with fiberglass or rocker panels?

That is a really cool test, but I question the claim about body filler being non porous.
In this example I feel the primer was protecting the body filler from absorbing moisture.
Years ago I block sanded and exposed a penny sized spot of filler, but mistakenly painted the panel anyway.
The filler soaked up the paint and it looked terrible, had to sand it down, spot prime and respray it.
I know there's a few on the market that claim to be non porous, meaning the others are not?
Either way, dig the videos - so thanks 👍

Hands-down, you give the most honest and practical body work advice on FB. Thanks and keep up the great work!

can i use lacquer high build primer with urethane single stage without problems?

Thank you so much sir, Invaluable information, nothing beats the experimental evidence, this is real science being done right here !

Hello good sir. I just used a paint gun for the first time on a couple practice pieces with primer...and wouldn't ya know it, I've got questions. If you want to answer, here they are!
- how the heck do you pour a brand new gallon of paint into a small mixing cup? That was a rough start.
- how much time, generally, do you have before the paint starts drying in the gun? I mean, for primer the flash time is 15 minutes and I was worried. With paint I'll be especially worried between coats.
Anyhow, that's all. It went smoothly enough to where I can't wait to do it again, so that's good. Thanks man for everything.
-DIO

Thank you Brother ! Great information ...i primed the roof n hood of my old Toyota Landcruiser three weeks ago ,hope to paint it soon.

I replaced the fender panels on the bed of my 2012 Ram 2500. I sprayed multiple coats of primer on it with a rattle can. I am looking forward to seeing if any rust came through after a winter of snow plowing in Maine. I didn't have time to finish it before Winter showed up.

As usual Jerry great job at spreading Your vast knowledge with those of us who probably know less than You have forgotten....lol.

It didn't rust because it wasnt drove on actual roads

Thanks for the video, I've always wondered about how long to leave primer in the elements and now I know!

Awesome

Good video. I’m not a fan of Lacquer primer in never stops shrinking. You think you got coverage after bodywork. Looks great all the sand scratches are filled ready for paint. Paint job turns out great give it some time in some cases months and you’ll see all them sand scratches. Being that it never stops shrinking it will show. The primer shrinks right into the scratches it once filled. I get it Lacquer dries fast easy to sand and it’s price is right. But it’s not 1970 anymore much better products. Not knocking Jerry he does good work. I have friends that still use Lacquer primer themselves. My personal opinion I don’t need customer coming back for the wrong reasons. So UPOL rapid cure is my go to 45 ready to block. Once again not knocking Jerry just the primer Lol

I've never had that problem either, but I've always kind of made sure it wasn't thin if I was gonna leave it out.
Great video 👍

Jerry is on it again. Thanks Jerry for making me fast .

Beautiful illustration on how to properly use lacquer primer and putting it to the test. Thanks Jerry 👍

I wish my hands moved as fast as yours. Ha Ha.

Thanks for this information and busting the myth

Awhile is fine, years is not. Primer mobiles rust eventually. It depends upon the environment you live in. Arizona you might be able to wait forever
In Michigan you might make it till Christmas. I work in the south now and rarely deal with rust. In Michigan 95% of my work was rust. I can leave metal bare for days here. Up North it would rust looking at it, it seemed like.

When I was a poor kid my car was in primer for years! lol

It happends on our ride too. I cant finish it since we got to use it for delievery on everyday basis. The only time I get to work on it is when days off. I applied body filler directly on bare metal too and applied epoxy primer atleast. ( And never got to finish it untill now hahaha ) After 2 years of daily driver beater rain or shine it didnt delaminate or didnt rot the filler beneath it. But the gray color on the epoxy primer dulled out. EP are vulnerable to UV rays but it keeps your metal and filler water tight. I conclude this test is 100% LEGIT. as long as you dont apply filler in already rusted metal it will be ok. Or atleast you dont scratch your primer down to metal it will not rust. This vid is helpful.

Great video sir. How about a follow up video of how long you can leave base coat before top coating?

jerry you are faster then a da lol love it .god bless jerry.

Nice little video. That's a good thing to know I was always told that it would rust if left outside in the weather. Keep up the good work and have a great weekend

Nice myth busting vid.😎

sseen this to be correct, but now you have me wanting to ask a guy around here, he built a 1950's Dodge truck, he has drove it all the time since I was a young man, over 30 years, he is an old hot rodder, but its gray primer and flames on front end, with custom checkerboard paint inside cab, but i dont think he resprayed it as flames looked same all my life, so a primered truck for over 30 years, saw it in last 2 weeks at store. but i figure his is lacquer, but who knows, i did a few vehicles with epoxy in early 1990's so it was around.

Another great 👍🏻 one to inspire us do it your selfers

great video as always,have a good weekend

Great video Jerry, I definitely was told lacquer primer would rust out over time when I first started painting cars!

100%,enjoy your tool time. I'm really for more

I like this video shows a lot in a little time and the 11 months is Michigan months

Wow. I would have expected more rust than that after 11 months outside. They myth is busted !!
Gotta love a real life experiment.

Interesting stuff Jerry!! Back in the 70's I would drive multiple vehicles around in lacquer primer for years without any problems!! I do remember seeing other vehicles in primer with some rust starting to bleed through!! It always seemed to be the grey, never seen it happen with red oxide, I wonder why!!☻

You waited 11 months for parts???

Bless LOVE videos like this. Thanks 😊

I've never understood the guide coat application. I do know you put it on to find highs and lows but it's put on so sparingly. Meaning there's a botch of black then inches of nothing. Another botch of black etc. The areas where there isn't any makes it tougher to see the high and low spots I would think. Why not make it all one uniform color?