Dude, your a motor killer, try changing the thermostat
to a 170 or 160 degree, and use a good small engine oil
Castrol or Mobil 1, I go to Costco and get the Chevron
5-30 Winter, 10-30 Mild Weather and 20-50 Hot Weather.
The #1 thing I have found for long engine life, other than
keeping the oil clean and full is let it warm up, don't drive
an ice cold engine, give it 2 or 3 min to warm, it's not hot
yet but the oil is warming and flowing to all the parts, if
you can stand to give it 5 Min all the better, if you must
drive it cold, go real easy no full throttle, just barly press
to get going.
I knew a girl in high school, many moons ago, who got
a new car for her 16th birthday. We had an open campus
so at breaks or lunch we would go to buy somthing, well
she would rev the S*i+ out of that poor car from a cold
start and drive the P*55 out of it, by the end of the
school year it was blowing oil smoke all over the place,
I learned my lesson at her expence, and saved many $$
in longlived engines.
Change oil every 5000 Miles !!, it is easy to keep track of
so you don't have to remember your mileage, change the
filter every time. Remember Motor oil is the most tested
fluid on the earth, and oil of 10 Years ago is nothing like
the new stuff, it is so much better just in 10 years.
I drive a Semi, standard oil change is at 10,000 Mi, some
companies have gone to 30,000 Mi, testing every 10K mi
and have found the oil is good for more miles than they
were getting out of it. In the case of a big truck, service
costs $500 so you can see the savings right away, I don't
reccomend going that long in your little cars, as $20 per
change is not too hard to afford.
Hope This Helps,
Darrin