Underseal..

[Dwighet]

Lads after just recently changing out my rear bushes for poly bushes I noticed a good bit of surface rust on the underbody especially around the axle brackets...

What would ye recommend product wise to treat the problem.
Id preferably like to tackle from the fuel tank back for now then up front at a later date..

I have access to an air compressor so I don't need aerosol cans and would rather spray than use use a brush...

Any advice would be greatly apreciated

 

[gingerdave]

Dinitrol products.Check their website.I've used them for years.

 

[Dwighet]

Dinitrol products.Check their website.I've used them for years.

so this should do the trick????
http://www.rejel.com/rejel-store/txtsearch/din01l/list/1.aspx" onclick="window.open(this.href);return false;

 

[gingerdave]

Yep I normally do cavities with clear or brown wax .Then all underbody with brown cavity wax Then a coat of black finnigans or Dinitrol equivalent. The wand they supply is quite cheap and is not robust..

 

[Frank]

Dinitrol products.Check their website.I've used them for years.

so this should do the trick????
http://www.rejel.com/rejel-store/txtsearch/din01l/list/1.aspx" onclick="window.open(this.href);return false;

Yep, apart from the RC900 Rust Converter spray that they include in some of their kits. The volatiles in that are bordering on the criminal, both on application and on residual fume effect. It has no business being used anywhere near 'Joe Public' and any scientist will tell you the same.

All products like this have a 'Safety Data Sheet', so find it and if you don't understand it then find someone who does.

If any of you ever wondered why your kids developed headaches and needed to urinate very frequently after you'd done your freshly undersealed motor with that...well, now you know. Dinitrol is good, but it's not the new Messiah and all their products need to be individually checked.

For rust conversion use, just use a water-based converter/primer like Vactan and all will be well.

 

[Dwighet]

Ok so..
Vactan sounds a lot safer than the dinitrol rust converter...Thanks for the heads up Frank..

Now preparation..... Do I blast the underside down with my Karcher then wire brush all I can...
Then spray the vactan...
Spray cavity wax in cavities and all surface areas..
Then underbody wax over the cavity wax on the surface areas and not in the cavities/box sections????

I have never done this before so bear withme please..

 

[Frank]

Now preparation..... Do I blast the underside down with my Karcher then wire brush all I can....

No. Iron and iron products are crystalline materials that are microporous to both liquids and gases that enter the inter-crystalline spaces. In other words, even when they look dry, they might well not be. The commercial sector uses water pressure sprays, but also has floor heater fans and scientists who have tested and told them exactly how long those fans have to be on for.

It's July, it's dry, it's a great time for this. Just go straight in with the wire brush.

Incidentally, rust itself is very hygroscopic (attracts water) so that's why rust makes more rust - like leaving a plate of table salt out in the garage overnight, in the morning it will be very damp, same thing.

Spray cavity wax in cavities and all surface areas...

I did just the cavity areas with the cavity wax and the surfaces all got brush painted with 4921 Underbody wax. Brush or spray, always do 2 coats of anything (allowing each to dry) to ensure you've covered properly and 4 coats on sharp corners - see, for example, how all the plates underneath the car have rust starting on their edges on this car? - http://www.pumapeople.com/stuff/1254334447/gallery_15801_274_73544.jpg" onclick="window.open(this.href);return false;

You could use the Vactan everywhere, but I did just existing/suspect corroding areas and obvious vulnerable areas, like brake lines, fuel tank,edges, seam folds, etc. Not all those areas are truly vulnerable, but they are damn tiresome if they were to rust through!

Inside the rear arches? - remove any excess rust. 2 coats of Vactan via spray or just squirt using a 5ml pipette to runoff point (access is tight in there) allowing both coats to dry. Follow with 2 coats of 3125 Cavity wax and you're done. With the cavity wax, it's even more important to allow each coat to dry as the volatiles (bit like white spirit) in the second coat will interact with the first and you could get runoff (coating too thin higher up)

Incidentally, here's what a Safety Data Sheet looks like. This is the one for RC 900 - https://www.google.com/url?q=http://www.dks.at/fileadmin/userdaten/datenblaetter/service_und_werkstattprodukte/en/Dinitrol_RC_900_1100810.pdf&sa=U&ved=0CBgQFjABahUKEwi-1NHekufGAhUF7BQKHZBWASM&usg=AFQjCNFPJx-Y2v4FYXvgq6-OvhH44H2RLw" onclick="window.open(this.href);return false;

Hope that all helps a bit.

 

[Dwighet]

Frank that's perfect..
I appreciate your time and effort..