Bolt

[bdm7250]

In the case of the top motor mount, I think it is more of a lost bolt rather than a broken one.
With a 1/2-20 bolt, the tensile and shear forces between grade 5 and grade 8 are that high, that I don't think in this situation for a top motor mount, would be something to worry about. My 07' manual does not specify the need for a grade 8.

1/2-20 bolt
tensile strength grade 5- 18159# grade 8- 22674#
shear strength grade 5- 14730# grade 8- 17870#

We deal with a slightly different standard of bolt in the structural steel industry, however strength characteristics are very similar. A grade 5 bolt has the same basic chemical and physical strengths and properties as an A325 structural bolt which is used in the vast majority of structural connections of any steel building. Grade 8 bolts are comparable with the rarely used A490 bolt, which are used in situations to sustain large dynamic loading. The chemical makeup of a grade 8 bolt is such that it makes it more brittle than that of a grade 5, therefore it is more susceptible to brittle fracture than a grade 5. A grade 5 bolt with a tensile strength of 120,000psi and yield strength of 92,000psi is quite adequate to sustain the loads applied in this friction type connection. Just my though, which means about this much..

 

[bdm7250]

With the last six words and the emojis

Figured you would..

 

[BWG56]

With the last six words and the emojis

 

[bdm7250]

 

[cdogg556]

In the case of the top motor mount, I think it is more of a lost bolt rather than a broken one.
With a 1/2-20 bolt, the tensile and shear forces between grade 5 and grade 8 are that high, that I don't think in this situation for a top motor mount, would be something to worry about. My 07' manual does not specify the need for a grade 8.

1/2-20 bolt
tensile strength grade 5- 18159# grade 8- 22674#
shear strength grade 5- 14730# grade 8- 17870#

Great info Ker!

We deal with a slightly different standard of bolt in the structural steel industry, however strength characteristics are very similar. A grade 5 bolt has the same basic chemical and physical strengths and properties as an A325 structural bolt which is used in the vast majority of structural connections of any steel building. Grade 8 bolts are comparable with the rarely used A490 bolt, which are used in situations to sustain large dynamic loading. The chemical makeup of a grade 8 bolt is such that it makes it more brittle than that of a grade 5, therefore it is more susceptible to brittle fracture than a grade 5. A grade 5 bolt with a tensile strength of 120,000psi and yield strength of 92,000psi is quite adequate to sustain the loads applied in this friction type connection. Just my though, which means about this much..

Well I just got schooled! Great info Douggy! Impressive!

 

[Bigkev007]

In the case of the top motor mount, I think it is more of a lost bolt rather than a broken one.
With a 1/2-20 bolt, the tensile and shear forces between grade 5 and grade 8 are that high, that I don't think in this situation for a top motor mount, would be something to worry about. My 07' manual does not specify the need for a grade 8.

1/2-20 bolt
tensile strength grade 5- 18159# grade 8- 22674#
shear strength grade 5- 14730# grade 8- 17870#

I am trying to figure out exactly what size bolt to get for the cameltoe motor mount I lost mine

 

[pauly]

View attachment 59570

 

[pauly]

This is for carb. 08 Mastiff... models yours might be the same.
Item 7 is 3/8 - 16 x 1" SHCS chrome
9 is 1/2 - 20 x 1-1/2" SHCS chrome (mutt) 1-1/4" (K-9, Pitbull) 1-3/4" (Mastiff)

Paul.

 

[Bigkev007]

This is for carb. 08 Mastiff... models yours might be the same.
Item 7 is 3/8 - 16 x 1" SHCS chrome
9 is 1/2 - 20 x 1-1/2" SHCS chrome (mutt) 1-1/4" (K-9, Pitbull) 1-3/4" (Mastiff)

Paul.

Thank you this has been very helpful I need bolt number 9 also upon looking further I also need the washer and I believe that there is a rubber grommet that goes inside of their stopping the boat from going all the way through

 

[Bigkev007]

Bolt not boat‍

 

[pauly]

You're welcome.
Half an inch stainless washer on mine no rubber grommet.

Paul.

 

[PacoPetty]

Y'all's knowledge fascinates me!