Each month we receive an overwhelming flood
of technical questions from our readers. Everyone at ATVR including the night janitor carries an extremely heavy workload, so as a last resort we were forced to put Mike Newsom in charge of answering your questions. Mikey is one of the most talented mechanics we know, but it's his off-the-wall remarks and repulsive attitude that keep him locked away in the garage. If you dare to bear his response, send your questions to firstname.lastname@example.org
. We promise not to let Mikey use your name and embarrass you in front of your buddies.
Ask: I recently purchased a Crossrunner 250 ATV for a very low price because I just couldn't turn down the great deal. Now I am trying to find parts for the rear brakes and not having any luck. Whoever owned it had completely removed the rear brake system. It has no lever for brakes and has no brake drum or hardware. The wheel mounts to the hub and the ATV works fine but lacks brakes. Any help you can provide would be appreciated.
Mikey: Sounds great, I have an unbelievable deal on a timeshare that you may be interested in as well. Just kidding, that would be as bad as admitting that I had purchased this China-made Crossrunner with missing components. I've always recommended buying these units in pairs so you'll have at least one set of spare parts available to keep one machine operational. It sounds as if someone may have taken my advice and has laid the parts quad off on an unsuspecting buyer (this would be you). Fortunately for you, I have had some luck locating a few Crossrunner dealers. I'm not going to name the dealers and promote these machines, but I'll tell you that they can quickly be found by performing a Google search. It's possible that one of these dealers could point you to a parts distributor if there is one. Good luck, and if your search fails, you could always consider buying a second Crossrunner for a parts machine.
Ask: I have a 2002 Yamaha Breeze that smells like oil when it's hot. Not only that, it also leaks oil out of the hole on the bottom of the gas on/off switch when it's very hot. The oil will leak everywhere, causing smoke when the oil touches the hot engine. The gas tank has a hose that goes into the gas on/off switch, so I'm praying it's not gas that's leaking. What could be the cause of this issue?
Mikey: The questions that reach my inbox never cease to amaze me. From what I understand, you can't distinguish between gas and oil even though it's dripping from the petcock/gas on/off switch? That should certainly be a dead giveaway to even the untrained eye. Park that Breeze and visit your Yamaha dealer to purchase a new petcock before you blow yourself up! A petcock rebuild kit may also be available, but I would be afraid to recommend this procedure after reading your inquiry. After a well-supervised install you should thoroughly inspect your ATV for any other leaks before, during and after riding. I don't wish to see or hear about you on the evening news.
Ask: I let a friend ride my 2003 Suzuki Z400, and he went up a small hill but didn't quite make it and started coming down backward. Freaking out when he began to gain speed, he hit the rear brake and flipped the quad over backward. It wound up on its side, and he didn't immediately turn it upright. After letting it sit for a few minutes and turning the starter over several times, it started without any problem. It will take off fine and run through the gears with plenty of power, but when I come to a stop the quad wants to die. Then if you hammer the throttle, it will die instead of giving power. I can nurse the throttle and keep it going, but I didn't used to have to do that.
After playing with the idle screw, I can get it to idle but not very well. I was thinking the fuel-air mixture needs to be leaner and the quad is bogging because of too much gas. I'm not sure why that would change just by being flipped. If it was in the correct position before, why would it be wrong now? I was thinking it might be a clogged vent hose or air line. I don't know what else it could be. Please suggest any possible things to check before I tear completely into the quad. I have experience with two-stroke MX bikes but not with four-stroke ATVs. I can handle carburetor stuff, but I really won't try getting into the engine.
Mikey: First off, carburetor adjustments shouldn't be necessary due to a rollover. With your previous MX bike experience, you should know this. Now, thanks to your inexperience you'll have to contend with misguided alterations in the carburetion while troubleshooting your true problem. This always adds a little unwanted excitement to any project. Your issue does sound fuel related, and it could be due to debris restricting fuel flow in the carburetor. This trash could have been in the bottom of the fuel tank or carburetor bowl and made its way up into the pilot jet after the shake-up. The pilot jet controls idle to one-eighth throttle, and this seems to be where you're having issues. Get it clean and let me know if this solves your troubles.
Ask: I'm looking for the head torque and value adjustment for a 2003 660 Grizzly. I can't seem to find it anywhere. Any help would be greatly appreciated. Thanks in advance from West Virginia.
Mikey: Apparently, you haven't checked the obvious location that is sure to contain this information: your service manual! Without this factory manual, which contains all specifications and troubleshooting procedures, you'll be relying on hearsay to maintain your machine. This could lead to an additional tongue lashing from Mikey in the future. I'm going to give you the details you need this time, but in the future you'll have to do your own homework. Intake valve clearance 0.004 to 0.006 inch (0.10 to 0.15mm), exhaust valve clearance 0.006 to 0.008 inch (0.15 to 0.20mm), and if you're at a point where you need to torque the head bolts, then you'll require more than just head torque specs.
Ask: I'm having a problem with my 2001 Polaris Sportsman HO. It started out with the fan not working and getting hot, so I replaced both sensors. The fan still wouldn't work. I then wired the fan direct with a toggle switch to make it run, and now the battery runs down overnight. I have been unable to find a short in the wiring. Do you have any suggestions that I can try?
Mikey: Stop replacing parts and hacking into your wiring harness before you cause some serious damage. These sensors and switches are in place to operate the fan when necessary and to conserve power. If you know the fan works and you've already replaced the sensors, then you know there is a problem elsewhere. You could possibly have a faulty ECU that's not turning on the fan, and you may also want to test the voltage regulator to be certain your machine is charging properly.