WTK How to fix discoloured engine plastics?

[damieG82]

Will like to get some advice on rejuvenating (and protecting thereafter) plastics found under the hood, namely the various fluid reservoirs (brakes/power steering/coolant). They become discoloured over time, sometimes to the point where you have to shake it to see the fluid level inside.

Here's an example of what I'm talking about... seen here on an Audi A4, but its a problem with just about every car I know of

New


Discoloured


Can anything be done, or is the only fix new reservoirs?

[rollingstock]

Not much you can do, regular deterioration of the plastic from heat of the engine and fluid building up deposits causing a change in colour, regular cleaning and the use of a protectant ( like amorall) should slow the process and keep the plastic from getting brittle with age which is inevitable.

[damieG82]

well the only 'fix' I found online is to clearcoat the outside of the reservoirs... I guess when they're in new condition. The article spoke about using a Rustoleum heat resistant clear coat product. Guess I'll try in due course

[sigma-turbo]

ok heres a little trick if its a coolant reservoir thats gone brown from block mud

remove it drain and dry it then 1/4 fill it with fine gravel (2-3mm size) and start shaking
once you feel you have done as much as you can drain the gravel and 1/4 fill with sand and start shaking again

make sure you flush all the sand

[dreadman]

^^^^ i usually do dat with mines

[~Vēġó~]

that gravel/sand trick sounds interesting!!!!

[damieG82]

^^ it does... will try it, but that still leaves the other 2 reservoirs

[3stagevtec]

If it's your brakes reservoir, maybe a fluid change can help improve the look of things.. I did a brake flush last 2 months ago and now the fluid is so clean that you can hardly notice the level in the reservoir and the plastic itself shows nice and clear..

Previously, my brake fluid was kinda on the brown side and that made it an eyesore..