Sea Rider
Supreme Mariner
- Joined
- Sep 20, 2008
- Messages
- 12,345
During a full powerhead restoration done moons back, 3 bolts out of 10 broke inside case due to salt build up between bolt threads and case threads. Had to be removed heating with a propane torch the adjacent area of the seized bolts to fully cede and retrieve.
This operation has weakened one of lateral threads of the case, on a second restoration when removing this particular bolt some thread portion was pulled, the portion is visible on lower bolt pic. Although can still screw in the bolt won't be to 25 NM tech specs or will risk pulling the whole thread. which intend not doing so.
Don't know why new bolts when removed from cylinder head looks so rusted and in a bad shape, a light coat of waterproof marine grease is applied to bolt bodies and internal case threads cleaned to perfection to avoid that nasty issue, but seems is not working as it should. Have learned that all salt oceans don't have the same amount of salt contents. The South Pacific seems it's the worse of all, precisely where like go boating.
Would you say that's impossible to pretend for head bolts to come out as when new ? Experiences dealing with bolts and salt water use are welcomed...
Happy Boating
This operation has weakened one of lateral threads of the case, on a second restoration when removing this particular bolt some thread portion was pulled, the portion is visible on lower bolt pic. Although can still screw in the bolt won't be to 25 NM tech specs or will risk pulling the whole thread. which intend not doing so.
Don't know why new bolts when removed from cylinder head looks so rusted and in a bad shape, a light coat of waterproof marine grease is applied to bolt bodies and internal case threads cleaned to perfection to avoid that nasty issue, but seems is not working as it should. Have learned that all salt oceans don't have the same amount of salt contents. The South Pacific seems it's the worse of all, precisely where like go boating.
Would you say that's impossible to pretend for head bolts to come out as when new ? Experiences dealing with bolts and salt water use are welcomed...
Happy Boating
