I just picked up a 2003 Scrambler 90 that’s locked up. Previous owner has no idea what her ex husband did to it but says her kids rode it 5 years ago. I’ve done top end rebuilds and realize I’m probably going to go a lot farther into this one (honestly that’s why I bought it, as a learning thing). Wiring harness is all hacked up so I’m going to need to replace that after I rebuild or replace the motor. So my first question is where do I start to determine how much damage is done? I removed the body and gas and oil tanks tonight to make access easier. I guess my plan is to start on the top and and see what it looks like. Any pointers on where to get started and If it comes down to it, where to look for a used engine and wiring harness?

anyone know how i can get access to a service manual? I’ve got a lot of wires missing and even some photos If completed quads would be helpful

 

Well I can spin the fan with no problem and it moves the piston smoothly. The kick starter is locked up. I sprayed it with some pb blaster and will do that for a few days to see if anything loosens up. I’ve never been into the crank case so I don’t know what else that could be connected to if anything (I see the gears where it would engage the crank shaft )

 

Sorry. Cant help at all with this one

 

Posting back here for anyone else. This quad clearly spent a lot of time outside. The Kickstarter was locked up but piston was free. Sprayed the heck out of the kick starter and removed the nasty filter from the crankcase and coated everything in there with pb blaster multiple times. Eventually the Kickstarter broke free for hand use (didn’t want to force it with my foot) and after more spraying it moves down and rebounds up on its own.

This one Is still a ways away from starting. Wiring is cut and the carb is toast. I actually went ahead and removed the entire engine so I can paint the frame and probably do another top end rebuild. I’ll be back with more issues.

 

My first thoughts were also that it probably spent years outside. I dont have much input on this one yet, but will check back to see how it's going, and see if I can help.
How did the oil look when you drained it?

 

Got the motor up on a bench and ordered new rings and gaskets. Got a question about the starter. If I jump it with 12v direct from the battery to the positive and the ground, it should crank right? It moved the fan just a tad (not even a 10th of a rotation) but definitely didn’t turn over. Everything on the motor is free so I’m guessing something is wrong with the starter?

 

FYI for anyone with similar problems. Apparently when these things sit (Outside)they really do lock everything up with rust. Starter turned fine off motor, ended up hitting the starter gears with some wd40 and let it sit a few days. Was able to move the gear with a screw driver so put the starter back in and it turns over fine.