Yanmar 3QM30

[gmjosey]

The cover over the thermostats was leaking and I found that the bolt on the left(facing aft) was not gripping at all. When I took the unit apart, the hole for that particular bolt was eaten away on one side.

Can this hole be filled with welding or brazing while in the boat and tapped with new threads ?

[dandrews]

Originally Posted by gmjosey

The cover over the thermostats was leaking and I found that the bolt on the left(facing aft) was not gripping at all. When I took the unit apart, the hole for that particular bolt was eaten away on one side.

Can this hole be filled with welding or brazing while in the boat and tapped with new threads ?

Check the Internet for something called a helicoil. Made for just this type of problem.

Don

[gmjosey]

Thanks. I know about helicoils,but there is not enough material,now,to accept one. What I want to know is if it is possible to replace the lost material by brazing or welding. And,if so,could I bore and tap it ?

[40 South]

You say you know about helicoils but have you used them? They require a larger hole to be drilled and tapped to accept the helical for the original bolt size. Can you put a helicoil inside a larger one (i.e. use two helicoils in the same hole)??

You may be able to use one of the epoxy metal putties.

[gmjosey]

I removed the exhaust manifold and took it to a shop where they replaced the lost material. A new hole was drilled,tapped,and a helicoil installed.Looking good for now. I will order a new exhaust manifold to erase my anxiety !