Corrosion to sills by rear wheel arches - is this common?

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My Name: PVR

Posts: 5
Joined: Thu Mar 17, 2016 5:59 pm
Model: C3 2002-2005, Original shape model
Year: 2003 (03)
Engine Size: 1.4
Fuel Type: Diesel
Mileage: 110
Trim Level: VTR+
Gearbox: Manual 5 speed


Thanks for your replies folks and the encouragement - it makes a difference ;)

Also thanks for the suggestions for squirty rustproofers, I'll check them out but by all means keep the useful suggestions coming!


PS Here is a link to a very interesting 'Classics Monthly' test of cavity waxes - enjoy :D ... s-on-test/
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My Name: C3CAR

Posts: 2734
Joined: Wed May 04, 2011 10:01 am
Model: C3 2002-2005, Original shape model
Year: 2002 (02)
Engine Size: 1.4 (16v)
Fuel Type: Diesel
Mileage: 140000
Trim Level: Exclusive
Gearbox: Manual 5 speed
Engine name: DV4 16-valve diesel (90 PS)
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PVR wrote:PS Here is a link to a very interesting 'Classics Monthly' test of cavity waxes - enjoy :D ... s-on-test/
Thanks for the link. I am waiting for their update in 2016, that would be very interesting to see the results for. ... s-on-test/
web archive has a copy of the article :D and I have pasted a copy here:
Cavity Waxes on Test

The cavity waxes update from the third and final* year of the independent Classics Monthly long-term anti-rust test

First published in issue 190, this is the second of two updates for year three. Click here for the External Coatings update. *Our long-term test is now in its final year and we will announce the winners at the end of it. That isn’t the end of the test though – we will continue to monitor and report on the treatments, hopefully until they crumble. This will provide invaluable long-term feedback for both manufacturers and consumers.

First published in issue 190, on sale May 2012.

It’s been a winter of discontent for our test products. Rather than spend their days languishing in a dry garage, as your cherished classic hopefully has been, they’ve been thrown to the elements since last October. Perched four metres up, in full exposure to the West Country’s weather patterns, the test pieces have emerged, dirtier certainly but just how compromised? Our last update (Issue 183, November 2011 cover date) concluded that time was telling on some of the cavity wax treatments.

All the cavity waxes should have been re-applied by now by a diligent owner before the winter of year two. Ours had held up well, with none tested compromising the steel. Entering year three, product limitations and endurance is beginning to show. The external treatments have seen the test pieces shunted from show to show during 2011 and around our workshop without special handling. How have they stood up to the inevitable knocks and bangs they receive?
The UK’s longest running anti-rust test of its kind uses no gimmicks or accelerants to age the products. This is real-time testing, so expect the same of any of the products here.

February 2010 – Needs to be heated to 120 degrees C and applied using a bespoke gun. We applied it at a slightly lower temperature, but coverage was good.
January 2011 – Hardly dried at all. Still looks like goose fat!
September 2011 – No sign of this one drying out yet. Has picked up dust and dirt like the others but remains waxy to the touch. Heavily pawed at shows when on display.
April 2012 – Picked up airborne dust from a local stonemason’s but remains waxy and solid. Baking sunshine hasn’t caused it to move. Can it be bettered?
MIL-Spec 3215

February 2010 – A very thin coating that wept from the lower sill join readily, so it’ll easily populate areas between spot-welds.
January 2011 – Still looks good. Now tacky rather than waxy.
September 2011 – Has become drier to the touch since our January update. No signs of cracking or shrinking.
April 2012 – Now dry to the touch and hard where build-up is present. No signs of cracking though and the steel remains protected.

February 2010 – Applied with a spray gun applicator – kit-supplied applicator failed. Good overall coverage and joint seepage.
January 2011 – Looks good. Sat at bottom okay. Starting to dry out a bit – tacky rather than waxy.
September 2011 – Has remained as tacky as it was in January without signs of cracking or contraction. Also heavily pawed when displayed at shows.
April 2012 – Dry to tacky to touch and quite hard. Some tracking cracks from shrinkage. Very minor surface rust near cracks.
Noxudol 700

February 2010 – Aerosol with probe made application easy. Requires a number of access holes to apply due to probe length. Coverage and seepage good.
January 2011 – Still a nice, even coating, and retains its waxy quality.
September 2011 – Still has its supple waxiness and is as good as we reported in January. The thin coating shows no signs of shrinkage or breaches.
April 2012 – Hasn’t changed at all since our last report. The metal beneath the thin coating looks like new steel. A very impressive start to year three.
Caprotech RX7

February 2010 – The most impressive so far in terms of ease of application. Gave excellent coverage with good seepage.
January 2011 – Still tacky inside. Hasn’t moved or settled at all. Just gone on and stuck. Looks impressive.
September 2011 – Has become considerably drier to the touch than in January, but has not split or shrunk. No signs of it thinning out.
April 2012 – Now completely dry to touch. Where adhesion has been lost, surface corrosion has taken hold and is spreading.
Bilt-Hamber Dynax S50

February 2010 – Easy to apply. The thinnest coating on test once applied, but seepage was better as a result.
January 2011 – With the exception of Noxudol and Korrosions-schutzfett, it’s not as dry as the others.
September 2011 – Tacky to touch, rather than waxy. No signs of degradation, however. Still looks like the most consistent thickness on test.
April 2012 – Almost dry to the touch now. Surface rusting in vertical lines suggesting the coating has been breached where moisture has been running over it.
Our verdict so far…

The good news to take away from this update is the standard of all the tested products is demonstrably high. All the exterior coatings bear witness to excellent adhesion where lesser treatments would have long since been breached.
When used last year on our Project MGB car, RustBuster 121 was applied to a couple of components in error. Having to remove it by hand, we discovered how tough it is, even in a sandblasting cabinet. Caprotech’s glossy finish cleaned up a treat and is worthy of its mention at this stage.
The cavity waxes have the tougher task in that they need both adhesion and the ability to reseal if necessary. Simply turning the test pieces has affected some as they run to gravity. The Korrosions-schutzfett’s goose fat-like consistency is showing no signs of shrinkage or drying out. It’s impressive stuff. The big surprise though belongs to the aerosol-applied Noxudol 700. It was simple to apply and is showing no let up in protection.
The test will then remain ongoing until ultimate winners can be declared. It could take years, but then you’d hope so if it was your classic car.

This entry was posted on Monday, November 5th, 2012 at 5:14 pm and is filed under Products, Tech. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a comment, or trackback from your own site.

Tags: anti rust update, Bilt Hamber, Caprotech RX10, Caprotech RX7, cavity wax, Dynax S50, Eastwood Rust Encapsulator, Electrox, Korrosions-schutzfett, long term, Mil-Spec 3215, Noxudol, Noxudol 700, POR-15, Rust Bullet, Rust Seal, Rustbuster Epoxy-Mastic 121, S50, Waxoyl, year 3

| Products, Tech | 05/11/2012 17:14pm
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