lexan = trouble down the road
Joliet;5565 said:
That is what I was thinking about using. But it would depend on what the temp of the oil is. The Lexan would be good for 240 degrees extended use, but I would be more comfortable at 220 degrees for extended use. If the temp of the oil will be compatable with the Lexan, I can get a sheet and cut a bunch of these up for thread members. Does anyone know what the oil temp runs?
The Lexan would probably work for a while, however, with materials all conditions must be considered. Lexan is a brand name for polycarbonate. It's great stuff until it is subjected to organic carbon-based compounds such as motor oil. Motoroil is chocked full of of fossilized organic carbon-based copounds, even most synthetic versions. These compunds attack the material even at room temperature. Add in the extreme heat generation of a modern 4-stroke engine and it just speeds up the process. What we have discovered is that PC under normal temps will take this ind of exposure for only a few months. Submersing it in such a compund and heating it for about 4 hours puts about 4 months worth of "normal" exposure on the material's molecular structure. When the PC parts are subjected to such conditions, the material actuall turns white and brittle and then fails catastrophically.
I am not a materials expert, but have dealt with this in depth through my engineering work. We had a customer that had a partiular vaccine that was reacting with the PC in our vaccinator barrels, turning it white and brittle and causing the barrels to literally crumble. I was even able to duplicate the process using cotton seed and linseed oils. The chemicals that build up oil is being subjected to heat, metals, friction and shearing in a motorcycle engine only speeds up the process. In this case, I wold say that Lexan would work for a while, but whill ultimately fail, or at least turn wite enough that you couldn't read your oil level.
I employed the knowledge of an expert materials engineer who had been working at GE materials for 25 years before enturing out and starting his own business and engineering his own materials. I have recieved most of my materials education from this guy (Dave Saldo, CRC Polymers in Rochester, NY who is also an avid dirt-biker, though he rides a KDX, but I don't hold it against him) and dicovered that almost everything wll break down PC or "Lexan". It's chemical resistance is essentially nil, and subjecting it to these types of conditions will put you in a situation where you will most likely have to replace it every so often.
I think the best scenario would be to replace it with a factory set p and put it back as it was. Then, put that neat little guard over it made out of PC. The PC or Lexan guard will add mondo impact resistance, and keeping it away from direct contact with hot motor oil will definitely keep it from reacting and braking down. The PC will handle ud and dirt just fine, but hot motor oil not so much. The other option you might have is if you can find a sheet of a material called "Xylex" in the corect thickness. You could definitely use that for a sight glass. Xylex is a PC blend. It would have all the impact resistance and toughness of PC, but is chemically impervious to almost everything. The down side is a sheet of it would probably cost as much as a payment on you cool new Husky. CRC polymers has a competitve material to Xylex that costs less than half, but i is only available in its base resin form for injction molding, which is how we use it. It is not available in sheets. Therefore, I think the best bet here, again, would be to put the stock glass back in and put that cool guard over it, making it from PC. It will stay clear and keep your factory glass from breaking and becuase it's not coming into contact with that scorching hot oil, will not be expoed to something that will attack it. Unless you spill gas on it...
Hope this was informational. I don't like to get too technical, but I thought some might be interested in the technical pointsof PC or "Lexan". It's cool stuff as long as the only thing that ever hits it is water and air.
p.s.-my typping suckz...I now.
