I may be getting older, but I refuse to grow up!
Join Date: Jun 2012
Location: PACIFIC N.W.
Hi im working on a friends 660 raptor kept blowing 3 head gaskets so he gave it to me to fix i usually work on 400 and 450s. starts up fine blows white smoke. So i took it apart the cam was messed up and head no oil to cam and head gasket blown. So i found a head head yamaha check it out and resurfaced head found out oil pump was bad so replaced oil pump and check outconecting rod no damage to rod. But cylinder bad too so new fresh cylinder and piston with rings install refresh head and timing chain installed. Adjust valves and she started up ran fine. Drove it on my trails no problem went to start it up the other day. she head hard time starting on compression stroke and i noticed bubbles coming threw radiator after doing leak down test. Now idk much on raptors so i hoping it just didnt do sumthing right but i follow a yamaha book. So if anyone has a idea let me know thanks
I'm more into Raptor 700's, but this may be true for the 660 too. ALWAYS use a factory head gasket. The 'Cometic' brand has a high failure rate.
On another note, the water pump seal could be leaking into the motor.
WELCOME TO THE FORUM.
'19 Can-Am X3, RS Turbo, 172 HP, 1300x15 STU #2 paddle, Tribute front, DynaTec controller, cat delete, GTP blow off valve, custom flame wrap, Bent Metal windshield, Blazer wiper, rear window, 48in LED light bar, 14in LED light bar, GTP LED side lights, S3 shock tower brace, aluminum rear pull plate, 5K Badlands winch, dual batteries, 5ft lighted whips, Rugged radio and intercom, interior lights, rock lights, chase lights, over $200 additional switches, YES, street legal with dirt tires.