Notices

Corrosion on engine bolts

Old 01-17-2017, 07:24 AM
  #21  
Senior Member
Thread Starter
 
Join Date: May 2011
Location: Merritt Island
Posts: 181
Default

Update:
Bolts were replaced, parts & labor covered by Yamaha. Replaced with same Yamaha Factory Bolts, tech used marine anit-seize / anti corrosion compound when reinstalling and then painted the exterior.
Iuse2Fish is offline  
Old 01-17-2017, 07:39 AM
  #22  
Senior Member
 
Join Date: Mar 2010
Posts: 1,587
Default

Thank you for posting results. For a year old engine, that is severe rust, to the structural level. Yamaha is fixing the problem.
wezie is offline  
Old 01-17-2017, 08:04 AM
  #23  
Senior Member
 
Join Date: Aug 2016
Location: Holland, Michigan
Posts: 1,084
Default

I would replace the nut with a cap nut and forget about it. Looks like there isn't enough thread showing to make that difficult. If there was more thread showing, I'd add a cap nut on top of that nut.
Attached Images  
30West is offline  
Old 01-17-2017, 08:17 AM
  #24  
Senior MemberCaptains Club Member
 
Join Date: Aug 2004
Location: North East
Posts: 1,066
Default

Originally Posted by 30West View Post
I would replace the nut with a cap nut and forget about it. Looks like there isn't enough thread showing to make that difficult. If there was more thread showing, I'd add a cap nut on top of that nut.


so hide it and pretend it isn't there... not sure I understand your logic. would it be better to get it fixed under warranty and take steps to ensure it is greased properly to avoid from happening in the future?
ck_moniz is offline  
Old 01-17-2017, 08:48 AM
  #25  
Senior Member
 
Join Date: Aug 2016
Location: Holland, Michigan
Posts: 1,084
Default

Originally Posted by ck_moniz View Post
so hide it and pretend it isn't there... not sure I understand your logic. would it be better to get it fixed under warranty and take steps to ensure it is greased properly to avoid from happening in the future?
I'd clean up the rusty tip, take off the existing nut and evaluate the remaining threads. Most likely there is no damage past the exposed tip, and a cap nut will prevent any further corrosion. I'd put a little thread locking compound on the threads before the cap nut, to seal the threads.

Grease or paint on another identical stud will be a temporary fix.
30West is offline  
Old 01-17-2017, 10:08 AM
  #26  
Senior Member
 
Join Date: Sep 2013
Location: on the road / Ft Lauderdale
Posts: 2,855
Default

I have a 2001 mercury 150 with the same problem. Rusting bolt with a.s. lock nut. Bolt is stud on forward part of lower unit , which attaches to motor housing. Have painted top, greased top and after awhile it will appear again. Stud is not rusting below nut. I wonder if the new stud that was installed will do the same ,or is there a recall on all Yamaha's150 's with this problem. What was dealer explaination?
deckape is offline  
Old 01-17-2017, 12:17 PM
  #27  
Senior Member
Thread Starter
 
Join Date: May 2011
Location: Merritt Island
Posts: 181
Default

Originally Posted by deckape View Post
I have a 2001 mercury 150 with the same problem. Rusting bolt with a.s. lock nut. Bolt is stud on forward part of lower unit , which attaches to motor housing. Have painted top, greased top and after awhile it will appear again. Stud is not rusting below nut. I wonder if the new stud that was installed will do the same ,or is there a recall on all Yamaha's150 's with this problem. What was dealer explaination?
When I picked up the boat yesterday the mechanic wasn't sure what the "factory" excuse was.. I didn't see the service managers car, don't think he was there.. Told me this was the 1st that he's done with this issue. I want to know too..

So would the acorn nut with thread lock seal it??
Iuse2Fish is offline  
Old 01-17-2017, 12:25 PM
  #28  
Senior Member
 
Join Date: Mar 2014
Location: Miami
Posts: 702
Default

Wow, what a timely thread for me. Just the other night I was going over my 2014 F115 and found the same bolts rusted out. The rest of the motor is tip top, but these two bolts are pretty bad. Some tiny pieces fell off onto my hand when I touched it. Just texted my neighbor who is a Yamaha tech. Let's see what happens.
Attached Images  
El Faster is offline  
Old 01-17-2017, 01:53 PM
  #29  
Senior Member
 
Join Date: Jul 2011
Posts: 5,081
Default

Originally Posted by Iuse2Fish View Post

So would the acorn nut with thread lock seal it??
I should think so.

Of course the head of that bolt can rust, too - its just hidden behind a cover....
Fwpratt is offline  
Old 01-18-2017, 07:05 AM
  #30  
Admirals Club Admiral's Club Member
 
Join Date: Mar 2014
Location: Charleston, SC
Posts: 28
Default

I just checked my 2015 Yamaha 150 engines and both have the corrosion on the bolts. I'll be giving my dealer a call today. The boat is a 2016 with only 120 hours on the motors.
Hot Shot 24 is offline  
Old 01-18-2017, 07:15 AM
  #31  
Senior Member
 
Join Date: Aug 2016
Location: Holland, Michigan
Posts: 1,084
Default

Originally Posted by Iuse2Fish View Post
So would the acorn nut with thread lock seal it??
Yes it would. I like to use low-strength thread locker wherever I don't need medium or high-strength, because it forms a plastic-like seal in the threads.

The mechanic should know the thread size you need, and acorn or cap nuts are very cheap.

A higher-strength bolt usually has higher chromium content, slower to rust. I wonder what grade these are? Someone said grade 8? A picture of the head would show the markings identifying what grade bolts these are.
30West is offline  
Old 01-18-2017, 07:58 AM
  #32  
Senior Member
 
Join Date: Jul 2011
Posts: 5,081
Default

Originally Posted by 30West View Post
A picture of the head would show the markings identifying what grade bolts these are.
Perhaps not:



It seems Yamaha has used an "acorn nut" for this application - but only on some models:

Fwpratt is offline  
Old 01-18-2017, 08:07 AM
  #33  
Admirals Club Admiral's Club Member
 
Join Date: Jun 2008
Location: Inlet Beach, FL
Posts: 1,312
Default

My 2014 looks the same way. Keep us updated.
wmflyfisher is offline  
Old 01-18-2017, 08:45 AM
  #34  
Admirals Club Admiral's Club Member
 
Join Date: Jul 2016
Location: FL
Posts: 824
Default

Same thing on my brand new 26 Chriscraft, I bought it new from the dealer, it has twin 200HPs I don't think it's a mistake, Yamaha has to have a reason behind it
tommy099431 is offline  
Old 01-18-2017, 01:54 PM
  #35  
Senior Member
 
Join Date: Aug 2016
Location: Holland, Michigan
Posts: 1,084
Default

If that ^ is an actual pic of the bolt in question, it is not a standard bolt. Custom, I'm not sure why a standard bolt would not have worked, but best to try to make it work by protecting the end.
30West is offline  
Old 01-18-2017, 02:28 PM
  #36  
Admirals Club Admiral's Club Member
 
Join Date: Apr 2008
Location:
Posts: 967
Default

This happened to some of my Yamaha bolts after just a couple of months (2013 F115) particularly the ones on the front below the cowling clasp and the Hyd steering unit (yes Yamaha parts). Also all the bolts at the cavitation plate that hold the lower unit on turned orange. They replaced them all under warranty but have never seen Yamaha parts rust like that. I was a little disappointed but hopefully they've corrected the issue. All I can think is they used lighter metals trying to reduce weight?
scflats is offline  
Old 02-02-2017, 01:24 PM
  #37  
Senior Member
 
Join Date: Mar 2014
Location: Miami
Posts: 702
Default

Just got a call from the dealer. Yamaha is replacing the bolts under warranty. Dropping the boat off Saturday.
El Faster is offline  
Old 02-03-2017, 07:30 AM
  #38  
Senior Member
Thread Starter
 
Join Date: May 2011
Location: Merritt Island
Posts: 181
Default

Originally Posted by El Faster View Post
Just got a call from the dealer. Yamaha is replacing the bolts under warranty. Dropping the boat off Saturday.
When I picked up mine from the dealer (marina) the office was closed so they're going to mail me the paperwork.. Still haven't gotten it so I'm calling to get it. Interested to hear what all the did to remove those bolts. Are you going to put the acorn nut on after? I'm going to order them, haven't yet..
Iuse2Fish is offline  
Old 02-03-2017, 08:02 AM
  #39  
Senior Member
 
Join Date: Mar 2014
Location: Miami
Posts: 702
Default

My neighbor from down the street is the tech that will do the work. I'll see him Monday when I pick up the boat. I'll ask him what he thinks about putting a cap on the bolt.
El Faster is offline  
Old 02-03-2017, 10:01 AM
  #40  
Senior MemberCaptains Club Member
 
Join Date: Oct 2003
Posts: 5,026
Default

Don;t worry about it but since you are worried, contact the engine MFG or dealer.

They built it like that for a reason. I suggest you leave it alone.

The bolt or stud needs to be high strength steel (I doubt you can get a stainless bolt/stud with the same strength rating). It goes through an aluminum housing and has a SS nut. They bonded it for protection. Looks like the did their best to make it strong and slow down corrosion. (No such thing as preventing corrosion 100%)
saltwaters is offline  

Thread Tools
Search this Thread