want to change piston on predator, do you have to pull whole motor or can you do it in place? plus do you have to pull the clutch basket out? or can you get the head and cylinder off with the timing chain guide in place? please advise. thanks.

 

you can pull the top end off without taking the motor out of the frame. be carfull and hang on to the cam chain so you dont have to remove the clutch cover. get it to TDC and take notice of where the timing marks are so you know how to put it together!

 

Why do you want to change the piston?

 

want to go with 12.5 piston.

 

Ok, I just did this..........make sure you have all of the info you need before you get to doing this, or it will cost you big time!!!! Trust me.......You can do it in frame.

Take off the valve cover, and look at what you are getting into(becareful with the valve cover gasket, you don't need to replace it).......Then, drain your coolant, and oil if ya want. Next, remove the cam chain tensioner(on back side of motor)........don't remove it by the 2 flange bolts, but by the one single middle bolt.....you need a key for this from your dealer!!!!! Otherwise you will not take the tension off of the chain........make sure you get the gasket off of that too, it is junk...........now you can start to tear the head down......remove the thing that holds the cams down, and the cams. Don't worry about the chain, i'd just drop it if I was you.......and worry about it later. I'll tell you how to get it into time later if ya ask. You don't have to use the gold links. If ya drop it, make sure you have a magnet......so when you need it, you can get it. then take off the head bolts........they are extremely tight!!!! Depending on year, remove your motor mount too........but remember you'll have to use heat, the bolts are thread locked in. Remove the head.....and gaskets(junk).......becareful on the head and cylinder both, not to loose the little cylinder things that hold it in place. then remove the cylinder. Take out the piston, and start putting it back together. Remember when you go back together, to oil the cylinder up really good, and the top of the head up really well too(lots of oil, just sitting in there).......You will not have to prime the oil pump, but will have to prime the fuel pump(will tell ya how later)..........Make sure you check end gap on your rings too........and oil the rings and wrist pin up good too. Torque everything to specs, and exactly how they tell ya too. Get a manual by the way. And make sure you banjo bolts are clean and clear when you go back together too(they have a oil line connected to them).......Get a new plug too.

 

crap, forgot to tell ya to remove the little alan "nut" thing on the left side of the quad in the cover. this allows you to see some timing marks. Align the marks(one behind the T I think).......and then check everything out when you look at the cams to see if the gold links are aligned and if the dots are aligned too. One dot on the cams should be about strait with the head, and the other should be about 7 degrees advanced. Then, before you remove them........count the number of links(so you can remember exactly how you did it).........between the dots.........this will help you in rebuild......so you don't have to use the crappy little gold links.


Also remember with your cam chain loose and in the motor(dropped).........you can't turn the motor over, or it will bind it.