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