Mercruiser 470 - 1987 Renken 1750.
Did a head job this summer for a faulty head gasket between 3 and 4, then found a crack in the head. Found a used head, machine shop worked it up, I installed it and it ran great! Ran great until on plane, and about 5 minutes it would begin to bog down with raw water being drawn into the carb via the crankcase vent. Riser and exhaust manifold are good. Could I have too long pushrods, not allowing the exhaust valve to close, thus drawing raw water in from the riser? Looking for other options if any has had this.
I know I may left things out that may be needed for this forum, but hoping I gave enough.
Thank you.
Did a head job this summer for a faulty head gasket between 3 and 4, then found a crack in the head. Found a used head, machine shop worked it up, I installed it and it ran great! Ran great until on plane, and about 5 minutes it would begin to bog down with raw water being drawn into the carb via the crankcase vent. Riser and exhaust manifold are good. Could I have too long pushrods, not allowing the exhaust valve to close, thus drawing raw water in from the riser? Looking for other options if any has had this.
I know I may left things out that may be needed for this forum, but hoping I gave enough.
Thank you.