Rust proofing/underside sealing


jesse888

Ek9+Turbo+Nurburgring= Heaven
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been looking into going over the rust proofing my ek9 has as its started to show surface rust underneath.
I've seen afew threads where you guys have done an epic job of the arches etc and wondering what products/methods you used to achieve these results?
I was planning on wire wheeling the whole underside and then using the POR15 treatment stuff.
This then needs painting over so what would you guys use then?
Also I'm going to rebush the car so I was thinking of getting all the arms powdercoated but would the POR15 do a decent enough job instead?

Feel free to upload some pictures of your work(before and after if pos) to this thread or link to your build threads so I can see what you've done.
 
Firstly do you have a compressor?

Which areas are needing attention? From my experience the floor pans and main arch areas are usually not affected by rust due to the heavy factory spray sealer so not worth trying to strip the whole underbody as to do this thoroughly takes an absolute age!
Perhaps post some pictures of your problem areas
 
The main areas are around the jacking points, both seals and the box section where it's caught the floor from being too low before.
The tank could do with a lick of paint and I've not had a decent look up around the spare wheel well because of the diffuser.
The arches aren't too bad but I'd like to cover them again, mainly to make them fresh.
I've had a gearbox oil leak that took me awhile to find and that's out oil all down the underside of the car aswell, so I'd like to clean that atleast.
 
Here's some pics of what I done with mine










Once it was back to bare metal I used etch primer, followed by a couple of coats of stone chip

Once this was dry I keyed it up with course scotch brite and then used a 2 pack top coat

For further protection against stone chips and general road crap the underbody has been over coated with dinatrol 4941 underbody wax and then had a further sacrificial coat of cheap black wax oil

Arches will be given a coat of bilthamber clear underbody wax.
 
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That's the kind of thing I'd like to do to mine, did you strip the whole underside down or just sort of clean and cover the existing areas that where fine?

Wire wheel on a grinder/drill job I take it?
 
@b16mini really good job that.

I would do it for you Jesse if I had a ramp. Probably take a week to do a good job.
 
The whole area around the tank and and jacking points etc was stripped with wire wheels and scraping/sanding by hand.

Rear arch inner lips were stripped and primed, coated with dinitrol 447 rubberised overpaint able stone chip and then painted the whole arch in white for the fresh look.

My floor pans were all good but I had to strip the corners back when I welded the cage foot plates in, so these were given the same treatment as the arches,

Front arches/inner wings and front panel received similar attention.

I've used this same method on loads of cars in the past and it's really lasted well.

For a track guy like your self a coat of underbody wax over it all is well worth while to help soften the impact of stones flicking up in the arches. The wax will not peel and flake like standard underseal either and it's easy to top it up with another light coat every once in a while
 
@b16mini really good job that.

I would do it for you Jesse if I had a ramp. Probably take a week to do a good job.
Cheers irf
This took me ages to do as I had little spare time, but I done similar to my siR and it took about a week
 
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