Okay guys.. I have a 1998 7.4 bravo 1 that I'm having some issues with. I purchased this past year and have been chasing a overheating issue since . I've replaced the manifolds.. elbows.. thermostat.. raw water impeller... and circulation pump on the block. I took it to the shop last month because I was having a fluctuation issue with the temp gauge. Mechanic installed a new impeller.. backflushed the system and replaced the thermostat with a 140*. Mechanic informed me that I had the wrong thermostat for the housing and that is what was causing the temp fluctuation because of a air pocket. He said it now says at 160 to 165 at idle on muffs. Fast forward to last weekend.. took it out.. once I got on plane over 2500 rpms it would start overheating . The overheating alarm went off. Backed off the throttle and shut it down. I tried it again with the same and results.. I ended up having to limp her back to shore at 2000 rpms . When I stopped in my slip I noticed a small wake hit the rear of the boat and saw steam coming off the back . The motor was already shut down.. went to the swim platform and touched the top of the outdrive.. it was hot.. hot enough where I couldn't keep my hand on it longer than a split second. When water would hit the top section of the outdrive it was causing the water to steam. The previous owner said he had the drive resealed before he sold it. My question is.. if the outdrive is bad.. could it put a bigger load on the motor .. enough to cause a overheating issue? Btw I did install a Hardin raw water pickup tube through the transom to rule out bravotitis along with a new hose from the transom to the raw water pump. At this point guys I'm stumped.. I'm tired of throwing money at it and the issue is not resolved. I'm getting to the point of just selling it out of frustration. Any help would be great.
