Underseal - what to do?
Discussion
Hi All
Have a Californian 67 Mustang that I have finally got through the MOT.
So next step would appear to be to underseal her now I am comfortable all the work on the underside is completed.
What should I do then?
I seem to be able to find different advice from all over the internet.
I assume I need to clean her down well underneath, do I need a pressure washer, a scouring pad, to mark the metal?
Do I need to get underseal just on the srface I can see, or into the rails, maybe make some holes for this?
Should I be painting it on, or getting a spray setup for it?
and waxoil or something else?
Have a Californian 67 Mustang that I have finally got through the MOT.
So next step would appear to be to underseal her now I am comfortable all the work on the underside is completed.
What should I do then?
I seem to be able to find different advice from all over the internet.
I assume I need to clean her down well underneath, do I need a pressure washer, a scouring pad, to mark the metal?
Do I need to get underseal just on the srface I can see, or into the rails, maybe make some holes for this?
Should I be painting it on, or getting a spray setup for it?
and waxoil or something else?
I'd recommend the Bilt Hamber range of protection rather than waxoyl.
For external areas I use the underseal product they make (both the spray cans and the stuff you 'paint' on) and for internal box sections etc. you can apply the Dynax S50 cavity wax - comes in bloody great 750ml cans with a long lance so you can be sure the wax gets everywhere.
With the underseal: put a coat on, leave it for 24 hours to cure and then re-apply. Make sure the cans are nice and warm (especially at this time of year) or the stuff won't flow properly.
You may well find that there are little access holes on your chassis outriggers or similar - you can use these to give the void a good coating of wax. If not, you can always drill a hole, carry out the procedure and then re-seal with a small rubber bung or similar. It's best practice to leave box sections open to air for a few hours to let the fumes escape and to give the wax time to cure/dry.
It's a dirty job to apply any form of underbody protection to a car but it's well worth doing, and doing well. Which is why I like to do it myself rather than relying on one of those companies who offer underbody protection services.
My Volvo Amazon (daily driver in all weathers) is very well slathered in BH products and the chassis is totally rot free. I make a habit of getting the car up on ramps/axle stands at least once a year to keep an eye on any issues with the underseal… it's a bit of faffing around, true, but a lot cheaper than welding.
For external areas I use the underseal product they make (both the spray cans and the stuff you 'paint' on) and for internal box sections etc. you can apply the Dynax S50 cavity wax - comes in bloody great 750ml cans with a long lance so you can be sure the wax gets everywhere.
With the underseal: put a coat on, leave it for 24 hours to cure and then re-apply. Make sure the cans are nice and warm (especially at this time of year) or the stuff won't flow properly.
You may well find that there are little access holes on your chassis outriggers or similar - you can use these to give the void a good coating of wax. If not, you can always drill a hole, carry out the procedure and then re-seal with a small rubber bung or similar. It's best practice to leave box sections open to air for a few hours to let the fumes escape and to give the wax time to cure/dry.
It's a dirty job to apply any form of underbody protection to a car but it's well worth doing, and doing well. Which is why I like to do it myself rather than relying on one of those companies who offer underbody protection services.
My Volvo Amazon (daily driver in all weathers) is very well slathered in BH products and the chassis is totally rot free. I make a habit of getting the car up on ramps/axle stands at least once a year to keep an eye on any issues with the underseal… it's a bit of faffing around, true, but a lot cheaper than welding.
If you are anywhere near Bradford, I have a pal with a garage who thoroughly enjoys squirting wax underneath interesting cars. 
He was trialling some new wax the last time I was there which he seemed impressed with. He has a profile on here. Paul is his real name:
http://www.pistonheads.com/gassing/profile.asp?mem...
He was trialling some new wax the last time I was there which he seemed impressed with. He has a profile on here. Paul is his real name:
http://www.pistonheads.com/gassing/profile.asp?mem...
RicksAlfas said:
If you are anywhere near Bradford, I have a pal with a garage who thoroughly enjoys squirting wax underneath interesting cars.
He was trialling some new wax the last time I was there which he seemed impressed with. He has a profile on here. Paul is his real name:
http://www.pistonheads.com/gassing/profile.asp?mem...
I know paul as wellHe was trialling some new wax the last time I was there which he seemed impressed with. He has a profile on here. Paul is his real name:
http://www.pistonheads.com/gassing/profile.asp?mem...
another recommendation for his 'hotwax' skills
he is a proper waxoil perv, loves getting filthy and covered in the stuff
If you mean "underseal" in the sense of the good ol' fashioned rubbery black tarry much, then... don't.
What you want to do is get everything on the underneath clean, and everything that's even remotely loose off - including old seam sealer from panel joints. You might want a hot-air gun and a scraper. Then get anything that's brown and crusty back to clean and shiny. Re-seal any joints.
You will probably want to start taking bits off to make life and access easier - figure out where you're going to stop, because that's a slippery slope...
THEN start painting. A good metal primer, and a similarly good top-coat. Doesn't have to be shiny. Brush is fine. Or use one of the many body-schutz type products if you've got access to a compressor and a schutz gun - you don't need a "proper" spray gun.
Then wax. Over everything, into everything. EVERYTHING. Most structural rot starts from the inside of box sections, because moisture gets in and can't get out. The schutz gun'll be invaluable again.
What you want to do is get everything on the underneath clean, and everything that's even remotely loose off - including old seam sealer from panel joints. You might want a hot-air gun and a scraper. Then get anything that's brown and crusty back to clean and shiny. Re-seal any joints.
You will probably want to start taking bits off to make life and access easier - figure out where you're going to stop, because that's a slippery slope...
THEN start painting. A good metal primer, and a similarly good top-coat. Doesn't have to be shiny. Brush is fine. Or use one of the many body-schutz type products if you've got access to a compressor and a schutz gun - you don't need a "proper" spray gun.
Then wax. Over everything, into everything. EVERYTHING. Most structural rot starts from the inside of box sections, because moisture gets in and can't get out. The schutz gun'll be invaluable again.
guru_1071 said:
RicksAlfas said:
If you are anywhere near Bradford, I have a pal with a garage who thoroughly enjoys squirting wax underneath interesting cars.
He was trialling some new wax the last time I was there which he seemed impressed with. He has a profile on here. Paul is his real name:
http://www.pistonheads.com/gassing/profile.asp?mem...
I know paul as wellHe was trialling some new wax the last time I was there which he seemed impressed with. He has a profile on here. Paul is his real name:
http://www.pistonheads.com/gassing/profile.asp?mem...
another recommendation for his 'hotwax' skills
he is a proper waxoil perv, loves getting filthy and covered in the stuff
but what sort of money are we looking at to get it done by someone else?
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