hello everyone. this an awesome forum here. i have been working on my 1999 gmc jimmy. my floor was wet i traced the water to up under the dash where the hood release cable goes into the engine compartment. it seems it is orginating from inside the windshied wiper cowling area and i cannot get to it to fix it properly from the outside. so,, i have disassembled my entire interior down to the fire wall. a huge project for me. any way. i see that the factory seam sealer is flaking off of the seams , so i sanded down to the bare metal as best as i could. my local car quest sold me some omni ppg 171/175 primer. he said to apply directly to metal surface after using a wax , grease remover . he sold me the duplicolor w g remover . so,, my air compressor is in storage, he told me i could brush it on as well. so i did. i mixed it 2 to 1. but it brushed on kinda thick i thought and it was really streaky. anyway, can anyone tell me if i am going about this correctly. im already getting surface rust on my floor boards and ive taked down the spots i have found so i need to get on this asap .

You should sand the metal with 180 grit to provide scratch for the epoxy primer to grab on to.
If you are using a really cheap paint brush it will be hard to get the primer on smooth. I am not saying to buy a top dollar brush but get one with soft bristles and paint the primer on.
Put two coats on and let it cure. I like the Urethane seam sealers like Lord Fusor 800ez that fit into a regular caulking gun.

If the PPG epoxy sits more than 72 hours you will need to scuff and re-apply before top coating.

Did you get the tech sheet for your primer? If not here: http://www.google.com/url?sa=t&rct=j&q= ... GU&cad=rja

Ooops sorry, I loaded wrong photo, that could've been bad, lol is there any way to thin that omni or just go with the specs I got the sheet with it. Thanks. Do I need to top coat that being its on the interior ? I didn't know if I could just put another coat of that omni and then use the seam sealer on it. Ive done and seen allot of painting on fiberglass boats but not much practice with auto, metal, etc

You can thin the PPG by adding Acetone (its on the tech sheet) but only up to 10%.

Yes, you apply the seam seal over the cured epoxy primer.

Epoxy should be top coated unless it will be covered by carpet, etc. I haven't used PPG in quite awhile and when I did it was the DPLF Epoxy so I am not familiar with MP series and its limitations.

Sounds like you got debris built up in your cowl. Not allowing water to flow out. Water is like eletricity flows path of least resistance.
Sealing from inside only. Still lets water sit in weld seams.

it is difficult with this weather but i managed to sand and prime the wiper cowl area i ordered some sealer and it should be here wednesday. im gonna try to re seal as much as possible inside and outside. i also plan on pulling the fenders again and scraping the factor sealer off from those seams as well. i also seem to have a slow drip leak from around the hood release cable that goes into the engingecompartment. i also saw a small rust line coming from behind the cruise control module thats mounted in the enginge compartment on the firewall. but it has been like 20 degrees here for two or more weeks.

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