Blistering blue barnacles!

[belfastguzzi]

The paint on my fuel tank is blistering. A section of the black paint layer has come off and underneath looks like a polythene bag with an air bubble in it. It looks like other sections are going the same way.

 

I wonder if this is similar to the condition that Al reported? I tried searches but can't find his posts. Anybody else seeing this problem? I can put up with some bad paint on the engine, but a peeling tank is much worse.

 

Matt black Scura.

[Alex-Corsa]

The paint on my fuel tank is blistering. A section of the black paint layer has come off and underneath looks like a polythene bag with an air bubble in it. It looks like other sections are going the same way.

 

I wonder if this is similar to the condition that Al reported? I tried searches but can't find his posts. Anybody else seeing this problem? I can put up with some bad paint on the engine, but a peeling tank is much worse.

Matt black Scura.

 

Can you post a pic here to see it. From when did this "phenomenon" start?

Is it partially over the days? Is it ORIGINAL MG paint there????

[belfastguzzi]

Yes, original MG paint. It seems to have happened just today. The paint around it looks pretty thin and it is on the rear of the tank, where most wear happens. However this is a low mileage bike. It's 2002, but only bought and put on the road at the end of 2003. No 'wear and tear'.

[Alex-Corsa]

Yes, original MG paint. It seems to have happened just today. The paint around it looks pretty thin and it is on the rear of the tank, where most wear happens. However this is a low mileage bike. It's 2002, but only bought and put on the road at the end of 2003. No 'wear and tear'.

 

The only think I can say of right now is that somehow somewhere sometime

There was some quantity of strong paint thiner medium (or paint remover :!: -or Batery fluid :!: )on your bike at this spot.(Factory)Paint just doesn't crack without a reason , If your tank was a repaint than I could surelly tell you that the first coats where too badly done, and or that there was a raipaint over the original with incompatible materials and false preperation, i.e. Laquer over urethane=alligator skin.

Though as you say you don't have this situation right now and to tell you the truth

it sounds like (though I'd have to see first)a severe paint damage.It may as well need the whole tank to be repainted.

[txrider]

In my experience blister failures have as their source something under the paint prior to paint application or penetration of solvent, moisture, whatever which collects between paint layers and causes localized intercoat adhesion failure.

I don't know about the paint MG used but the description is of a matt black Scura. Some flat and semi-flat coatings use a lot of flatting compound (sometimes silicone flour) which adds some porosity to that coating increasing the possibility of absorbing some damaging material.

IMHO the blistering paint problem described sounds like combination of property of the finish used and poor surface prep or insufficient film thickness applied.

Sorry if I sound like a know-it-all but I worked with these problems on instrument panel coatings for years.

Stripping and recoating is the preferred fix.

[Alex-Corsa]

Yes that's also verry correct txrider, I just coudn't imagine a factory paint to have poor preperation (on some short of).I have messed around doing paint jobs in tanks and helmets for a while as an artist, though I wouldn't say I am an expert on this subject.

 

Vehile companies do apply less (thinner)protective coats on their paints and though after and of the nineties the coat companies increased the persentages of the solids in their coats(that may lead to not needing any morethick coating),truth is still that the coats are not really "enough" they are too thin (for me)for the right protection.One little(in depth) scratch can easily hit the paint as well

 

I have therefore added a few more clearcoats at my Sport's tank last year hhmm...err As many as to make the sign of MG with the eagle at the point of not looking embosed any more (surface level samenow)

 

[belfastguzzi]

I'll post a picture when I get a chance.

 

Advice on repainting these plastic tanks would be welcome.

[Baldini]

Belfast,

 

You out of warranty now?

 

KB

[al_roethlisberger]

The paint on my fuel tank is blistering. A section of the black paint layer has come off and underneath looks like a polythene bag with an air bubble in it. It looks like other sections are going the same way.

 

I wonder if this is similar to the condition that Al reported? I tried searches but can't find his posts. Anybody else seeing this problem? I can put up with some bad paint on the engine, but a peeling tank is much worse.

 

Matt black Scura.

46877[/snapback]

 

 

Here ya go:

 

Bubbling Tank Paint Thread

 

 

 

....this seems to not be an uncommon problem, especially with the 2002 and earlier bikes that suffer from tank suck. Although it is not uncommon, I don't mean to suggest it is a "common" problem either... if you get my drift... but it isn't unheard of.

 

I don't know if my failure was from tank suck, but I had seen photos and heard stories of the paint on the tank failing in the same area as mine eventually did... the rear of the knee cutout. Check the thread above for more details.

 

Sorry to hear about this, but if under warantee... they'll replace it. If not, think of it as an opportunity for that cool new paint job you've always wanted

 

....oooor like in my case, an opportunity to go for a 2003 salvage tank and upgrade to the new in-tank solution, then sell your old tank(or the warantee replacement one) and come out just a couple hundred in the hole

 

And of course, since it is a Scura with the matte finish, you could always just try to touch it up. It should be easier than trying to do so with any other finish, although matching the black might be a bear, and you'd have to prep the surface with a special primer to get paint to stick to the poly

 

 

Sorry to hear you fell victim to MG's 2002 paint woes as well

 

al

[al_roethlisberger]

I'll post a picture when I get a chance.

 

Advice on repainting these plastic tanks would be welcome.

46902[/snapback]

 

 

In case it isn't covered in the old thread I linked to above, you can find more info in my various "tank" threads by searching on "tank". Check out the "wasted fuel" and "2003 retrofit" threads for more info on painting these tanks.

 

 

Basically though, you can't do it well/easily yourself. The tanks are made from a plastic, the same stuff those white cutting boards are made from, that is basically inert and nothing sticks to.

 

So, one has to have special primer and paints to adhere, and if not prepped perfectly, the paint is just going to come off again.

 

If you choose to repaint your tank, take it to a professional. I spent $300 color matching and painting my 2003 tank I got from salvage, and although expensive, the shop did a top-notch job. And I feel confident the paint will last a long time, versus something I could try to do myself.

 

But I sold my warantee 2002 tank for about $300 also, so I got about half my money back

 

al

[Alex-Corsa]

I'll post a picture when I get a chance.

Advice on repainting these plastic tanks would be welcome.

 

Tell me something else, is this Scura paint just a matt look finish , whithout any glossy clear coat over it?(tank and other bike paint)

 

ED. The tank is plastic??

[callison]

I just coudn't imagine a factory paint to have poor preparation .

46897[/snapback]

 

There was a 97 Sport 1100i at Moto Italiano four years ago that had the worst paint job I've ever seen on ANY vehicle (I had a Fiat 2300S one time that the former owner had painted with a house paint brush, and it didn't look as bad as this Sporti). Paint blisters that made the Scura crankcase popcorn look about average. Right from the factory. I've heard that the Mandello plant had a lot of leaky roofs before the Aprilia monetary infusion that repaired a lot of the factory. Perhaps there was (and may still be) a bit more moisture in there at times than there ought to be.

[belfastguzzi]

thanks, I was looking for blistered, rather than bubbling – I kept finding posts from people whose boots didn't ft right.

 

This isn't related to tank suck. It is on the rear, rather than the sides.

Yours looks different, but it could all be due to the same underlying cause i.e. a deficient prep/paint process.

 

Alex: the tank is indeed plastic and the finish is matt, there is no clear or protective coat.

[Alex-Corsa]

thanks, I was looking for blistered, rather than bubbling – I kept finding posts from people whose boots didn't ft right.

This isn't related to tank suck. It is on the rear, rather than the sides.

Yours looks different, but it could all be due to the same underlying cause i.e. a deficient prep/paint process.

 

Alex: the tank is indeed plastic and the finish is matt, there is no clear or protective coat.

 

I had a system reboot here and I'm back,

Well I would like to suggest you to whatever you do get the best materials there is.

Here is a good example:

-PPG-

After that you'll have to find a good pro to do the job.If you have no personal experience,enviroment and equipment leave it to the pros.Find someone that you have already seen his work and fits your quality of result.

I have made myself some coating on my Guzzi tank but even if I use airbrushes for the last 9+years it allways take much attention to get the desired effect. And to me that had to be a perfect glass looking coat.All companies do not accomplish that, you see if you go close ,very close to any paint job of any car you'll see the surface making some kind of very little waves...that's OK but it wasn't for me the case.

I could (can) analyse you how-why this is that way but it would be out of topic.

 

Back to the topic,well I'll post you a couple of links so that you EXACTLY locate

your problem and estimate yourself the extent of it.

 

LOCATE Paint Defect

Is a "Special link from PPG with all paint problems (Bar selector) that will rovide you with accurate description and tratment.

This is for paint blistering

Paint Blister

 

At first I thought you had something like this

Paint Pickling

 

You see English isn't my main language and also there are different ways on explaining a problem.(It may as well be sth else than what you named as blistering)

That's a reason pics are always important.

 

Here's what the page suggest for blistering

" Rectification Establish the depth and cause of the blister by pricking out with a pin and examining under a low power magnifying glass.

Where the blisters occur between paint layers, the affected area may be sanded down to a sound surface and repainted.

In more severe cases, or where the blisters occur between the undercoat and the substrate, strip down to the substrate and repaint. "

 

If your case is not so severe after sanding down to a sound surface (don't do it yourself),without the all of the paint being removed, it is very possible if done carfully that you may not need any additional painting work for the tank at all(because you have a matt finish).And that's the good news.

 

The bad news could be, to have a more severe paint defect and paint the whole thing.

 

Keep us posted

[Guzzirider]

Belfast Guzzi,

 

A Scura fuel tank on EBAY

 

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?Vie...7962744110&rd=1

 

Regards

 

Guy