I’m looking at an 87 LT 500 that has had a recently blown head gasket that was repaired. The base gasket was not replace. Now there are bubbles coming from inside the radiator when the machine is running. Are the bubbles being formed from a cracked jug, the base gasket, or else where? Keep in mind the quad runs perfect.

Thanks for your thoughts.

 

Is there a lot of white smoke comming from the exhaust? or does the spark plug have white crud on it? If not its probably OK, I have a quadracer 250 and when you rev it with the cap off I see what looks like bubbles, but its cause from the hot fast moving coolent hiting the internal passages of th radiator. Last thing, if your coolent level doesnt go down after 1/2 hour of riding I'm sure your OK.

 

YOU MADE NO MENTION OF OVERHEATING, OR ANTIFREEZE BLOWING OUT THE OVERFLOW. IF THESE ARE HAPPENING THEN YOU WILL NEED TO CHECK THE WATER PUMP. I HAVE ALSO SEEN COMPRESSION FROM THE CYLINDER LEAKING INTO COOLING SYSTEM AND BUBBLING THE COOLANT. IF YOU JUST INSATALLED THE TOP END YOU MIGHT ALSO HAVE SOME AIR TRAPPED IN THE SYSTEM WHICH WILL DISSAPATE AFTER A WHILE OR YOU CAN REMOVE THE BLEEDER SCREW FROM THE TOP OF THE HEAD. ANYWAY YOU MIGHT HAVE NO PROBLEM AT ALL JUST KEEP AN EYE OUT FOR ANTIFREEZE IN THE OIL OR AS MENTION ABOVE ON THE PLUG. ALSO LOOK FOR GAS AND OIL MIX IN THE RAD. IF HAVE HAVE NONE OF THIS AND NO OVERHEATING THEN CHANCES ARE YOU ARE OK. I KNOW THIS WAS LENGTHY BUT JUST GIVING YOU A FEW PLACES TO LOOK.

 

Thanks guys for the info. It gave me some good insight.

 

IT ALSO POSSIBLE THAT YOU HAVE EXHAUST GASSES COMING OUT OF THE RADIATOR. It woulsd be my guess that either the jug is bad or the one or both of the head gaskets are bad.

 

THAT'S WHAT I SAID WHEN I SAID GETTING COMPRESSION FROM THE CYLINDER THIS IS THE SAME AS THE EXHAUST GASES BUT THEY WAY YOU WORD IT MIGHT BE MORE HELPFUL IN EXPLAINING THAT. JUST THOUGH I WOULD THROW THIS IN AS NOT TO CONFUSE ANYONE.