Recently my son and a friend of his borrowed my 1985 quadracer without my permission and now it smokes horribly.They only rode it in my flat dry field and only put my pre mix gas in it.
I changed the gearcase oil and found fuel mixed in with the oil,can anyone help me figure out exactly what the problem is and how expensive it may be to fix?

P.S. son is paying for damages even if I have to sell his dirtbike!


Also would like to know if anyone knows where I could find a new engine for a 1987 LT250 quadracer,and if an engine from an 87 quadracer will work in a 85 quadracer?

 

Sounds like a bad crank seal. not hard to change. Just pull the clutch cover and clutch, then replace the seal.
For replacement motors, check with www.eastcoastatv.com

 

I have the same problem with my atv.
Exactly how hard of fix is this for a beginner to atv repairs?

 

Well, flipping through Dirt Wheels Magazine, I see that a company called Midwest Action Cycle sell the main bearings and seals in a kit for $58
If you have worked on bikes or quads at all, or have some mechanical experience and aptitude, it shouldn't be a problem. I would check the clutches while you are in there...since the gas in the trans oil will thin it out considerably.
Might just go pick up a Clymer's manual just in case you get into trouble

 

Sounds like your rings are bad and the gas runs and fills up the crank then eats throught the bearings. You may also want to check the compression on your bike. While you have it apart you should re ring the pistion. Also check for hairline cracks in the pistion. Most peolpe do not do proper upkeep on 2 strokes like re ring at least once a year.

 

sounds like your crank seals are shot.grab the magneto and move it up and down. any movement at all means the crank bearings are bad. you might as well split the cases and replace the crank bearings and seals and freshen up the top end.since it's an "86", it probably needs it!. then you'll be set for awhile.