Red7fifty

My Feedback: (73)

HI RCU people,
A friend of mine has this engine, and I have one that I bought from someone that shows the same symptom....deteriorated plastic. I have no idea what is causing this damage. On mine, it was run once by the former owner, that is all the info I have at this time, don't know if my buddy's was ever run.
Can any oil that you know of cause this? How about chemicals in the plastic fuel line, perhaps a bad mix of fuel tubing? What about if someone put gasoline in it, would that tear up the plastic? Any fedback from you rocket scientist type guys would be helpful, also feedback from anyone who has a random idea or has experienced this them self.
Thanks a bunch!

Pilotsmoe

I dont know what could cause that but i know you can get a new one at tower for $4 http://www2.towerhobbies.com/cgi-bin...?&I=LXB492&P=0

Red7fifty

My Feedback: (73)

Hi Joe,
Thanks for the reply, but only the black ones are available now, with the early vintage red one's being really hard to find.

ChuckN

I've heard of it called "plastic cancer". I think that's why you can't get red ones anymore. Apparently the black plastic is an improvement.

ZAGNUT

My Feedback: (1)

i have a medallion .15 that developed a large hole where the venturi is supposed to be and my medallion .049 has chalky blotches that can be scraped away revealing good plastic underneath.

i see the exact same thing on some of the interior plastic parts of a friends old subaru, since his dashboard doesn't use glo fuel i'm inclined to think that UV is playing a part in this "cancer".

religious use of a good automotive plastic/rubber protector might solve this problem but i haven't tried it myself.

dave

Red7fifty

My Feedback: (73)

Thanks for your feedback, that sounds exactly like what is one one of my tanks, chalky white soft material, and you can scrape it and make it red again, but it is missing a chunck of plastic. I don't think it is UV from the sun, since that would cause the anodize to fade and the blister card to bleach as well, but perhaps it has something to do with hydro-cloror-flouro-carbons-clorine-azine bleaching the chemicals out of the plastic, and feeding the plastic fuel line?????
(1) Vinyl dashboards in cars release some of the vinyl chloride used in manufacturing and results in a film on the glass, that is where that fog comes from.
(2) The United States Statue Of Liberty used to have a steel framework covered in copper plates, and when the copper tarnished, the steel would give up some of it's electrons to renourish the copper, and the cycle would continue untill the steel got so depleted that the Statue started to fall apart from lack of support. That is why they rebuilt the framework in stainless steel, and isolated the two metals with a nylon pad to insulate the metals from having one sacrifice itself.
(3) I have a jetski drysuit, which is waterproof, and has rubber seals for your neck, your wrists, and rubber socks. I used to store this on a plastic coat hanger in the garage, but after 1 1/2 years, I noticed that the neck rubber was dry and started cracking, right around the areas that was touching the plastic hanger, the wrists and socks were fine how ever, almost looks new, I left it stored that way, and as time went on, the condition of the neck seals got worse, but the rest of the suit is still in like new condition.

I am starting to believe that something is happening here that is similar to the above examples. Although why it happens to some and not others mystifies me. I have also noticed on one of my spring starters which is on an engine still sealed in the factory package has some white corrosion on it....maybe some chemical from the cardboard packaging? I think I will pull all the plastic fuel hoses off my display engines from now on.

Anyone else have this problem? Anyone have any damage to plastic parts from any types of storage oil?
Thanks for reading, and your time for all the replys!!!!!

Red7fifty

My Feedback: (73)

I just remembered that when I worked around pictures, they made a special sleeving for the negatives that was made from a special acid-free or sulfur-free compound. Maybe this is the key?

ChuckN

Very interesting!! And I thought UV was the unly thing we should watch out for