Lower mount bracket bolt broke

[upshootie]

On my 2014 DF250, the starboard side lower mount bolt broke. It looks like possibly cracked then started rusting since it appears to be regular steel with a stainless steel nut. the port side is rusty but not broke...... yet. I wonder if it could be replaced with a SS bolt and nut? Anybody else had this problem?
Thanks,
Mark

[catacom225]

SS Is is what you need, 304 or 316 with large washers and lock nuts, a little antiseize, and seal the hole with some good chalk

[Greg Moore]

Should be stainless! Besides the corrosion issues, SS is close to grade 8 and odds are very good whoever used plain steel didn't use 8's, probably not even 5's.. As mentioned, put anti seize on them, SS likes to gall to itself and being nearly grade 8, when it galls you'll have to cut or snap it and they're a brute to snap!

[upshootie]

I agree that bolts should be SS! The nuts are but not the bolt. You'd thing Suzuki would know not to screw a SS nut on to a steel bolt!! I thought Suzuki might have updated and went to SS bolts. Not! I ordered new ones.... Steel bolt... SS nut..... SMH.
I've researched and looked all over for 14 x 220mm and/or 9/16 x 9" ss bolt. Nope can't find them. I'll put these steel ones in and try put some type of anti corrosion coating on them.

[artdf175]

West Marine ? Maybe Lowe’s they have a large section put here anyway with SS parts
or call the number at the top of this page I would bet he has just about anything

[Harper]

I agree that bolts should be SS! The nuts are but not the bolt. You'd thing Suzuki would know not to screw a SS nut on to a steel bolt!! I thought Suzuki might have updated and went to SS bolts. Not! I ordered new ones.... Steel bolt... SS nut..... SMH.
I've researched and looked all over for 14 x 220mm and/or 9/16 x 9" ss bolt. Nope can't find them. I'll put these steel ones in and try put some type of anti corrosion coating on them.

I wouldn't blame Suzuki for that. Blame the boat manufacturer or the dealer. One or the other of them mounted that motor on the boat. Definitely use anti-sieze. Would also recommend that you use fine thread bolts and nuts, not coarse thread.
This is where I get all my SS fasteners https://www.boltdepot.com/Default.aspx

[upshootie]

I wouldn't blame Suzuki for that. Blame the boat manufacturer or the dealer. One or the other of them mounted that motor on the boat. Definitely use anti-sieze. Would also recommend that you use fine thread bolts and nuts, not coarse thread.
This is where I get all my SS fasteners https://www.boltdepot.com/Default.aspx

Harper,
These are Suzuki bolts. They are not the bolts that mount the motor to the boat. they are Suzuki part number 09100-14004.
Thee following link is a parts diagram for a DF250. the bolt is item #15.

Drive Shaft Housing Transom(X, Xx) (Df250t E03) - Suzuki OEM Parts - iboats.com

[Harper]

Sorry, I misundertood. However, Stainless steel might not be you best choice for the bolt. Stainless steel bolts are not as strong as grade 8, and not often used for structural purposes. Grade 8 bolts have a proof load of 120,000 pounds per square inch. The minimum strength of stainless steel bolts is 40,000 to 90,000 psi. The minimum strength of grade 8 bolts is 130,000 psi. Grade 8 bolts are much stronger than stainless steel.

Could be the reason why Suzuki didn't use SS bolt. But still doesn't explain why they'd put a SS nut on it.

[wilbur1]

Probably used a stainless nut to keep it from rusting to the bolt and not be able to come apart.

[Ethinksthat]

Checkout Fastenere for Grade 5 & 8 bolts - Bolts go with the yellow or plain. Black Oxide grade 8 will rust.