ATV Parts and Accessories

The cooling fan went out w/ no warning and temp guage went up in the red... Immediately shut it down and bought a new fan (havent had it put in yet, but havent been driving either) There is no white foamy residue on oil cap, but what I would describe as a rusty-ish brown residue. I know these cars have alum heads - Based on the oil-cap residue alone, is this now a bad motor for sure? I'm trying to decide whether to take it to a local shop (trustworthy, had work there before) or just put it in the garage until i decide what to do w/ it.
FYI, the car has 144k on it.

2) Explain why rain samples collected on thunderstorm days are more acidic than rain samples collected on non-thunderstorm days. Write an equation to support your answer. [4]

3) What would be observed fro ma reaction between aqueous chlorine and aqueous potassium iodide? [1]

4) Write an ionic equation with state symbols for reaction in Q3. [2]

5) Explain if there is effervescence when a magnesium ribbon is added to hydrogen chloride dissolved in methylbenzene. [2]

6) In the purification of water for drinking, what substance is used to remove unpleasant odours in water?
A) alum B) activated charcoal C) chlorine D) lime

7) When solid X is heated strongly, a gas is produced which turns damp red litmus blue. Which element must be present in X?
A) carbon B) chlorine C) nitrogen D) sulphur