Exhaust manifold broken bolt.

[Rickfri59]

1998 Volvo Penta 5.0 GL in a Larson SEI 226 bow rider.... I replaced exhaust manifolds and risers a few days ago. Everything came apart with no problem. When I was tightening down the very last bolt in the manifold assembly process the bolt sheared off. I was not prepared with tools to extract the bolt from the block so I finished the job crossed my fingers and started the engine. No popping sound or odor of exhaust in the engine compartment. Boat ran great all day. My question: Is not having one of the six bolts present securing the manifold a big deal? I plan on tearing it down in 6 weeks when I winterize it to extract the broken bolt. What is the worst outcome of not fixing this in the next 6 weeks? BTW my torque wrench sucks.

 

[alldodge]

1998 Volvo Penta 5.0 GL in a Larson SEI 226 bow rider.... I replaced exhaust manifolds and risers a few days ago. Everything came apart with no problem. When I was tightening down the very last bolt in the manifold assembly process the bolt sheared off. I was not prepared with tools to extract the bolt from the block so I finished the job crossed my fingers and started the engine. No popping sound or odor of exhaust in the engine compartment. Boat ran great all day. My question: Is not having one of the six bolts present securing the manifold a big deal? I plan on tearing it down in 6 weeks when I winterize it to extract the broken bolt. What is the worst outcome of not fixing this in the next 6 weeks? BTW my torque wrench sucks.

Don't see an issue so long as you can put your hand near the broken bolt and feel no exhaust leaking. If you do this will only get worst as time goes on. How bad the leak is will depend on what you should do next. Check again once engine has run a while.

Metal fatigue happens with exhaust bolts, not saying your torque wrench wasn't the issue but could also just be old studs

 

[Scott Danforth]

you should always use new bolts on exhaust.

 

[Bondo]

Ayuh,.... The manifolds are awfully rigid,...

So long as it ain't an end-bolt, it'll probably hold the gasket, til ya can fix it proper,....

 

[bruceb58]

you should always use new bolts on exhaust.

+++1. I do the same.

 

[Rickfri59]

Thanks to all for the advice. I used the new bolts that came with the (Made in the USA) kit.

 

[bruceb58]

Thanks to all for the advice. I used the new bolts that came with the (Made in the USA) kit.

You use a torque wrench?

Should be 12-18 ft-lbs so not super tight.