Troubleshooting: Verify you've got a blown head gasket!

Much has been said about troubleshooting a blown head gasket. Some true, some not so true, and some are just impossible to come by for many people.

In the case of QLink scooters, it really doesn't behoove someone to go ahead and verify- even with 100% accuracy- a blown head gasket. Why? Qlink doesn't care. They will NOT send you a head gasket, despite a very clear indication that this is the problem. They are NOT in the business of getting people back on the road quickly. If you disagree, do a quick internet search for it and read the accounts yourself.

The way I looked at it was this: if I verified, hands-down and for sure that there was a head gasket leak, I'd still have a big headache arguing about all the stupid shit they forced me to wait for. I'd rather simply suspect the problem, give them the chance to straighten it out, wait forever to get parts, try them, and ask again... until it finally got fixed; than to know and end up waiting just as long. I know; I called them myself and spoke to them. Don't believe me? Try it yourself.


In the meantime, here are the checks you need to perform to have a reasonable indication that you've got a leak; at least in the same capacity I had mine.

1. Does your scooter run hotter than the screw on the temperature gauge? Even in cooler weather? Does it blow coolant when you accelerate suddenly? Is your radiator coolant level low? (Like down to 1/3 capacity.) Is your recovery tank level low, despite adding more? Is your tank level high all the time? If you answer yes to these, keep going.
2. Stop the scooter. Allow it to cool. Take off the front shroud using a phillips screwdriver. Remove four screws on the rear side of the front fairing, and two at the bottom by the fender. Take off the COOL radiator cap. Don't burn yourself. If the tank is low, add coolant to the top. Start the bike. Once warmed up, goose the throttle to 1/2 or 3/4 full, very quickly, and let off. Do it again. If coolant pushes out of the filler neck, consider yourself 90% sure that you've got the problem. Check it a couple of times. It'll throw a shotglass or more of coolant every time you do it.
   
3. Remove the lower head bolt that is at the lower left hand side of the head. (LEFT = LEFT WHEN FACING THE FRONT OF THE BIKE.) You can get to this bolt without removing the valve cover. If it has ANY grey, rubbery, RTV like sealant on it, this indicates a scooter that was suspected of having leak issues at the plant. Perhaps they used it through all years, perhaps even after the fix; I do not know. What I do know is that it was on this scooter. Can you see this grey sealant around the hole? Oozing from the head/cylinder joint? Just another way to check.
   
4. Did you drain the coolant? Did you see black flakes of paint in the coolant? If you get flakes from your coolant, can you bend them without them snapping in two? If the latter is the case, and they're stringy, rubbery, or do not break- this is the coating from the head gasket. It comes off as a result of exhaust gas and high pressure passing over it. Some of the coating is within the combustion chamber, before the seal point of the gasket. This will be expelled through the exhaust. But what you're seeing is the coating that was blown from the gasket and into the coolant, as hot, high-pressure exhaust gas cooked it off and blew it there. Seeing this should make you very suspicious that you've got a gasket leak.
   
5. If you've changed coolant and flushed the system, and have run the bike for two hours or more, does the coolant still look nice and green? Does it look kind of stained? Brownish? This could be exhaust gas staining your coolant.

There is more to come.