78 x18 with 454 overheat prob

[VIC]

Just bought a 78 x18 with a factory 370 package. Runs cool on water hose but hot in the lake. Found the pickup pump impeller trashed and rebuilt the pump. No help still gets hot in the lake. I ran it at my shop at 1800 rpm for 20 min temp never went above 140. This boat picks up water on the transom not the outdrive. Any help would be great.
Thanks Vic
email vwormuth@bellsouth.net

[mrfixxall]

Just bought a 78 x18 with a factory 370 package. Runs cool on water hose but hot in the lake. Found the pickup pump impeller trashed and rebuilt the pump. No help still gets hot in the lake. I ran it at my shop at 1800 rpm for 20 min temp never went above 140. This boat picks up water on the transom not the outdrive. Any help would be great.
Thanks Vic
email vwormuth@bellsouth.net


check for leakge at the transom pick up,could be picking up air along with water.. also check the coolers for the rest of the parts from the inpeller..

[BUIZILLA]

also make sure the hose from the transom pickup to the pump isn't collapsing, it should be single wire inserted hose or triple wall lamination at minimum..