I would hazard a guess here based on the limited information you are giving. Sounds like a head gasket failure into the water jacket that is allowing compression loss into the cooling system.... bubbles. If bubbling increases with RPM... that is a dead give away. Sounds expensive if you aren't prepared to DIY.
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I would hazard a guess here based on the limited information you are giving. Sounds like a head gasket failure into the water jacket that is allowing compression loss into the cooling system.... bubbles. If bubbling increases with RPM... that is a dead give away. Sounds expensive if you aren't prepared to DIY. Oh and don't use a lighter to peer into the radiator the lighter than water fuel will rise to the top tank.
I would hazard a guess here based on the limited information you are giving. Sounds like a head gasket failure into the water jacket that is allowing compression loss into the cooling system.... bubbles. If bubbling increases with RPM... that is a dead give away. Sounds expensive if you aren't prepared to DIY.