Partzilla Live Q&A with John Talley – September 25, 2020
John Talley returns once more for another Friday edition of Partzilla live Q&A, taking on your motorcycle and ATV repair questions.
Yamaha ATV repair questions seem to be the most popular during these live sessions, and this was no exception. Check out excerpts from Partzilla’s latest live Q&A session below, and tune into our YouTube and Facebook channels every Friday at 3pm Eastern for the next edition.
Partzilla Live Q&A Highlights – Yamaha ATV Repair
Yamaha Grizzly Repair
My Grizzly 700 runs really hot. The overheat light never comes on, but you can hear what sounds like the coolant boiling when I turn it off after riding it for a while. Is this normal?
John Talley: I’ve noticed on the Grizzly 700s that they get hot back at the exhaust, because the exhaust is so close to the plastic, and good grief if you ever replace the plastic on yours, make sure you have that reflective tape or that heat-reflecting tape on the inside, otherwise it’ll melt the panels right off of it. … If you have access to a heat gun, take a couple of readings, especially if you’re hearing it boil. That almost leads me to believe that maybe it’s a little bit low on coolant … It may be running ok, but it’s not cooling adequately if you can hear something boiling in there. And actually your coolant shouldn’t really boil to begin with, so have you ever replaced it and flushed it out and if so, did you just do it with water or did you actually go back with the coolant that’s supposed to go in there? Because these machines are pretty finicky about what type of coolant you go back with. I wouldn’t recommend picking up the green stuff that you find at a local auto parts store … Typically they want that nice Yamaha cool blue coolant, so maybe it’s time to do a flush on that one and then refill it …
2007-08 Grizzlys have stator problems in the early models without the oil bypass pipe. Any solution besides an all new stator cover with a bypass oil pipe?
John Talley: I think I know what you’re talking about. I would say to update it. That would be the best way to go instead of having to replace what they had on there, which evidently is causing you a problem, so go ahead and update it.
Yamaha YFZ450 Repair
I have a 2007 YFZ450 that’s not cranking. I made sure the starter motor was getting power and I hear it but it’s not spinning. I took the damper gear out and the starter motor spins. Any thoughts?
John Talley: So you’re telling me that you actually removed the motor from the side of the engine and you can see the gear spinning on the end of it. That tells me that you probably have a problem with the reduction gear and a one-way gear in between your actual starter motor and where it’s actually turning the engine over. You may have to open up that side of the case and take a peek in there to see if you have a problem, because it sounds like something is bound up …
I have a brand new YFZ450 2020 and while I run the engine for warm-up, the exhaust header glows red after a few minutes. Is that normal?
John Talley: Actually it is because I believe on that particular model, the exhaust pipe is titanium, and those are extremely thin-walled because they’re trying to save weight. And when they get heated up, they glow red. It’s ok. Even going back to my son’s 2009 YFZ, it does the same thing. Interesting when we do night rides because I can look back and make sure he’s there. … but no, don’t be worried about that. It’s designed to glow a little bit red, but it’s ok.
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