Transit coating on exhaust systems

pfillery Insano Dub Head

734 posts · joined Dec 2011 · 14 Dec 2012, 12:38 pm

#935573

Found out from a supplier today that a new muffler system is often supplied only with a transit coating of paint which is not heatproof. As such after 6 months the paint will come off and the system will rust.

Could this be the reson there are so many rusty VW mufflers if they have a tendancy to come this way? I wasn't aware of this and clearly many retailers don't mention this fact.

Is this the case?

matberry Moderator Go hard or go home

8,114 posts · joined Mar 2006 · 14 Dec 2012, 12:58 pm

#935575

Yes, but the paint burns off in the first 30 minutes, not 6 months.

Matt Berry Motorsports...air cooled advice, repairs and mods Ph 0408 704 662
OFF-ROAD,CIRCUIT,DRAG,STREET,ENDURANCE

vlad01 Compulsive Aussie Vee Dubber

4,270 posts · joined Jun 2010 · 14 Dec 2012, 1:02 pm

#935578

Yes that is the case.

pretty much all the major exhaust manufactures use cheap crap coating to make the product look nice for sale purposes only.

even higher end extractors for the v8 boys only use a crap paint.

I bought a set of pacemakers few years back (sells from $500-700 just for extractors) and that actually has heat proof paint but its still crap. I sandblasted it and gave several coats of VHT exhaust ceramic/silica paint. Has held up for the past 3 years very well. few speckles of rust on the extractors underneath the car is just showing up now with 100,000km+ on them.

I would imagine VW exhaust to be even worse as they are cheap and nasty most of the time.

only option is have good quality exhaust stripped and ceramic coated or use VHT similar on them. If its mild steel it will rust with time regardless of coating.

stainless generally doesn't rust much but often suffers fatigue fractures over many heat cycles.

71 notchback,
Past owner of, 70 NB, 73 SB and 72 FB TLE

68AutoBug Beetle Restorer - Experience over 138\% - YIKES --

11,654 posts · joined Aug 2002 · 14 Dec 2012, 9:21 pm

#935638

pfillery wrote:Found out from a supplier today that a new muffler system is often supplied only with a transit coating of paint which is not heatproof. As such after 6 months the paint will come off and the system will rust.

Could this be the reson there are so many rusty VW mufflers if they have a tendancy to come this way? I wasn't aware of this and clearly many retailers don't mention this fact.

Is this the case?

Yes, mufflers and extractors etc are all coated with a very cheap paint, just to stop it rusting until its sold... lol

I wire brushed mine off and painted it with High temp paint
and it usually needs another coat every 12 months, but I don't drive far in my beetle.
My VW muffler I painted stayed painted for a few years before needing a respray..
but keep at it and they will stay un-rusted on the outside for
a long time..
some High temp paints are better than others...
and even some colors last longer.. lol

when the paint peels off, just wire brush it, and make sure its oil free and re paint it...
most Hi temp paint don't need an undercoat.. [rattle can]
just a few thin coats... [drying in between]

LEE

- Helping keep Air Cooled VWs on the road - location: SCONE in the Upper Hunter Valley - Northern NSW 320 kms NNW of SYDNEY---

vlad01 Compulsive Aussie Vee Dubber

4,270 posts · joined Jun 2010 · 14 Dec 2012, 10:08 pm

#935645

I never had my exhaust paint peel off with the brutal prep I do. its more that the stone blasted areas get speckles of rust, kinda like when your paint work gets chips on the front of your car and the chips themselves just rust and nowhere else.

I used VHT velvet black with about 5-6 coat straight onto prep washed bare sandblasted metal.

next time I'll chemically strip the cheap paint, molasses bath it for a day or 2 to etch the metal, sodium hydroxide bath to neutralize and temporally rust proof the metal, VHT exhaust primer (something I wasn't even aware of last time) then the final exhaust paint. I would expect rust proof finish for 5 years with continual use I recon from what I have experienced using VHT.

I found most VHT range far superior than what you buy at a auto paint store for the specialty applications, even against the big brands.

I used the engine enamel on plastic rocker covers, 3 years latter. still perfect and its not even designed for plastic lol. But its not the greatest on metal I have found. The caliper paint done the same sort of prep mentioned above has amazing results. Same with the vinyl dye, amazing!

71 notchback,
Past owner of, 70 NB, 73 SB and 72 FB TLE

pfillery Insano Dub Head

734 posts · joined Dec 2011 · 16 Dec 2012, 7:30 pm

#935882

I actually saw a VHT ceramic exhaust and header paint today, bit more pricey than normal heat proof paint but rated higher temp than normal ones. That may be the go when I get a new system.

Surprising that the system I was looking at was an empi, which I would have thought was ready to go and not transit coated.

shaihulud Custom Title Time!

1,448 posts · joined Nov 2005 · 19 Dec 2012, 4:39 pm

#936261

I used Caterpillar exhaust paint on the exhaust of the Manx SR.

Now that it is about 4 years old, it needs a new coat.

A single can will do it.

I bought it at a Caterpillar tractor parts store.

HappyDaze Superannuated

2,887 posts · joined Jun 2009 · 19 Dec 2012, 5:26 pm

#936265

shaihulud wrote:I used Caterpillar exhaust paint on the exhaust of the Manx SR.

Now that it is about 4 years old, it needs a new coat.

A single can will do it.

I bought it at a Caterpillar tractor parts store.

Sounds ideal for an 'ex-tractor' exhaust system.😂

I'd rather wear a Beetle out by racing it than by polishing it!