TRANSOM BOLTS SUZUKI OUTBOARD 115HP

[Karnic]

Managed to lift outboard up 1 hole with the help of a friend. My friend recommended to use new transom Bolts and not re use the original ones. A friend of mine had a new sealed set of transom bolts ( which he gave them to me for free ) same length and thickness,however they were the original mercury/quicksilver ones and not the suzuki ones. I installed the said bolts but after speaking with a colleague he said that maybe the bolts i installed are not for saltwater use. Honestly i am not an expert and all i can say is that in the new bolts there is stamped THE F593C in which i don't know what it means. Should i be concerned and buy the original suzuki ones for peace of mind?

 

[Beamishken]

If they are mercury transom bolts they should be fine the cap markings tell you they are 304 stainless . The origional bolts would also likely be fine too

 

[Rappey]

The only time i would not reuse the bolts if if they had crevice corrosion on them. I am surprised they are not 316 stainless, but since they clamp aluminium to the transom then 304 stainless is little concern as stainless and aluminium would be more of a problem, but stainless bolts and outboards seem to fare well.
I think 304 is non magnetic, but 314 is slightly, and 316 not at all.

 

[Assassin]

I simply use inconel instead.

 

[Karnic]

If they are mercury transom bolts they should be fine the cap markings tell you they are 304 stainless . The origional bolts would also likely be fine too

yes they are quicksilver ones with brass or bronze locknuts. The original ones looked fine but i got skeptical to re use them . the thing that is worrying me a bit is that the bolts i installed are slightly magnetic and the other ones are not although the washers are magnetic. I would have used the original ones but as i got the mercury ones for free i taught it will be better to install new. I leave boat in a saltwater environment for 4 months and i think it should not be an issue .

 

[Karnic]

The only time i would not reuse the bolts if if they had crevice corrosion on them. I am surprised they are not 316 stainless, but since they clamp aluminium to the transom then 304 stainless is little concern as stainless and aluminium would be more of a problem, but stainless bolts and outboards seem to fare well.
I think 304 is non magnetic, but 314 is slightly, and 316 not at all.

was going to re use the originals ones but as i got the mercury ( quicksilver)ones free i taught it would be better to install new ones. The ones i installed are slightly magnetic whilst the original ones are not at all although the washers were highly magnetic. I leave boat for 4 months in saltwater . What do you recommend? should i re install the original ones or see how it goes with the new ones? Heard that the mercury ones are also quality transom bolts so i think it will not be an issue. And everything is sealed now with sika.

 

[Beamishken]

yes they are quicksilver ones with brass or bronze locknuts. The original ones looked fine but i got skeptical to re use them . the thing that is worrying me a bit is that the bolts i installed are slightly magnetic and the other ones are not although the washers are magnetic. I would have used the original ones but as i got the mercury ones for free i taught it will be better to install new. I leave boat in a saltwater environment for 4 months and i think it should not be an issue .

Mercury supply lots of engines and many are left in the water almost year round. And many have been bolted on for decades & you never see one fall off or fizzing away due to the attachment bolts. Probably safe to say they will be fine for a good few years. Most are clear of the water at rest anyway. I have seen those alloy nuts deteriorate under water assuming they are the same as used on the bravo trim ram pins but they are permanently immersed and only after several years

 

[Rappey]

Ive had all sorts of outboard boats and they live on a mooring all year round. Had many different engines and when i need bolts i just raid my "bolt box" which consists of lots of recycled nuts, bolts and screws etc consisting of god knows what grade of steel.
If it looks like stainless as opposed to steel then thats ok for me. Had a 200hp bolted to a light aluminium boat (probably the worst scenario when it comes to electrolysis/galvanic corrosion), even put undersize bolts in as thats all i could find at that time and i can honstly say i have never had any problems whatsover with any bolts.
The two lower ones are often under water on long shafts of reasonable power.
Stainless bolt, stainless nyloc, sorted ! If the bolt is a chinese special you would probably see rust before it failed.
Its the top two bolts that are well out of the water that take most the strain as the thrust of the engine tries to pull the top of the mounting bracket away from the transom.
I,m sure any of the bolts you have will be adequate.

 

[STILL AFLOAT]

In the states, most outboard bolt problems, arise, due to the boat, being trailered along the Interstate, with the outboard stil bolted in place. Every bump in the road,makes the huge O/B, bounce like a ton weight ,wrecking bar.

 

[C08]

My new Yamaha 25 transom bolts are 12mm galvanized HT steel not stainless and my previous Tohatsu also had plated steel bolts.