Bolt replacement ! S.S. or not?
Printed From: CorrectCraftFan.com
Category: Repairs and Maintenance
Forum Name: Boat Maintenance
Forum Discription: Discuss maintenance of your Correct Craft
URL: http://www.CorrectCraftFan.com/forum/forum_posts.asp?TID=4630
Printed Date: January-17-2025 at 1:03am
Topic: Bolt replacement ! S.S. or not?
Posted By: Pete LHC
Subject: Bolt replacement ! S.S. or not?
Date Posted: August-27-2006 at 5:43pm
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I am in the process of replacing the exhaust
headers on my 80 SN. Is there any reason NOT to use Stainless Steel bolts as replacement? ------------- Thanks, Pete |
Replies:
Posted By: 79nautique
Date Posted: August-27-2006 at 5:48pm
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depends if you like your bolts to rust off or not.
Where did you get the headers? extremely rare for a 351W to have headers most like they are just manifolds. I would suggest using socket head caps screws over standard hex head fasteners. ------------- http://www.correctcraftfan.com/diaries/details.asp?ID=756&sort=&pagenum=1&yrstart=1979&yrend=1979 - 79 nautique |
Posted By: Pete LHC
Date Posted: August-27-2006 at 5:54pm
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My bad...I stand corrected....They are not headers.....just manifolds......
------------- Thanks, Pete |
Posted By: Tim D
Date Posted: August-27-2006 at 6:29pm
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Regular bolts should be just fine, just put a dab of anit-seize on them. ------------- Tim D |
Posted By: 79nautique
Date Posted: August-27-2006 at 8:27pm
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They will work but over the long haul caps screw are better and are easier to get off the next time the heads won's shrink as much they doen't get rounded off it provides more clearance as well and won't dig into the manifolds as much either. ------------- http://www.correctcraftfan.com/diaries/details.asp?ID=756&sort=&pagenum=1&yrstart=1979&yrend=1979 - 79 nautique |
Posted By: JEFF KOSTIS
Date Posted: August-27-2006 at 9:38pm
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Stainless bolts are great for "light duty" applications, but dont work well for future removal as they "gall" and snap off. Most stores sell 304 stainless bolts which are equivelent to a grade 2 standard bolt (no dashes on head). You can order and get 316 stainless bolts equivelent to a grade 5 bolt (3 dashes). Anything harder is more difficult to get. Even the 316 stainless will gall over standard bolts if overtightened.
A grade 8 bolt (of whatever head you need) offers better rust resistance and strength and would be my choice. My .02 good luck!! Jeff... ------------- MUSTANG COUNTRY http://www.correctcraftfan.com/diaries/details.asp?ID=1074 - 1974 Mustang 17 http://www.correctcraftfan.com/diaries/details.asp?ID=1093 - 1976 Mustang 17 |
Posted By: 64 Skier
Date Posted: August-28-2006 at 7:57am
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ARP is the only way to go. Their Stainless Spec is chromemoly 8740 (Grade 8 plus) or something thereabouts which is way better than 304, 316's etc.
------------- 64 Skier 66" HO VTX and 67" HO Triumph http://www.correctcraftfan.com/diaries/details.asp?ID=1071&sort=&pagenum=3&yrstart=1971&yrend=1975 - 71CC |
Posted By: GottaSki
Date Posted: August-28-2006 at 8:47am
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Yup, No surprise 316 will gall, 316 is for high purity plumbing; for bolts its gall-o-matic.
Its best purpose is inside process chambers; its quite misused elsewhere. ------------- "There is nothing, absolutely nothing, half so much worthwhile as messing around with boats...simply messing." River Rat to Mole |
Posted By: Rick
Date Posted: August-28-2006 at 11:46am
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i agree with Tim D I would use regular manifold bolts with antiseize compound. ------------- http://www.correctcraftfan.com/diaries/details.asp?ID=250&yrstart=1996&yrend=2000%20" rel="nofollow - 2000 Ski |
Posted By: jimbo
Date Posted: August-29-2006 at 10:32am
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Use cap bolts and anti-sieze for sure.
They have a smaller head than other bolts of the same thread diameter. I've been replacing my bolts with with kinda goldish bolts from the local hardware store. I think they are grade 8. Probably overkill on the strength side but they seem to have good rust resistance. Now, even though I have a background in Chemistry, I just don't fully understand this... On I/O boats, like Mercurys, they put these zinc anodes on the lower unit -- sacrifical anodes. Something about two dissimuliar metals and electro-chemistry. Anyway, our boats don't need the anodes but I'm always wondering if the bolt, or pin or what ever I substitute is going to cause a problem. Does anybody know what metals put together require the anodes? I think Aluminium is one. Does anybody know? |
Posted By: 79nautique
Date Posted: August-29-2006 at 6:17pm
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the I/O's have more aluminum in them that reacts with the steel creating electrolosis thus the need for anoids ------------- http://www.correctcraftfan.com/diaries/details.asp?ID=756&sort=&pagenum=1&yrstart=1979&yrend=1979 - 79 nautique |
Posted By: jimbo
Date Posted: August-29-2006 at 8:12pm
That's what I figured. The only freshwater boats that need them are the ones with a big hunk of aluiminum hanging off the a$$-end. I'm just not a good enough inorganic chemist to know what other metals are incompatable with steel. |
79nautique wrote:Posted By: 91nautique
Date Posted: August-29-2006 at 11:53pm
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Jimbo.
Does this help? Arranegment of metals in galvanic series CORRODED END (ANODIC OR LESS NOBLE) magnesium zinc aluminum cadmium Any of these metals will theoretically steel corrode while offering protection to lead to any other that is higher in the series tin so long as they are both electrically nickel connected. bra$$ bronze copper nickel-coppper alloys stainless silver gold platinum PROTECTED END (CATHODIC OR MOST NOBLE) Ive got an anod on the exhaust outlet of my boat,its wired internaly with S/S wire to the lift rings and onto the aluminium bracket that retains the steering cable,up and onto the motor so that it covers the shaft and prop. In salt water,parked up next to the houseboat with aluminium pontoons, the anod will last about three months. Fresh water it hardly wears at all. Great forum, thanks for all the ideas ive managed to "steal" from you guys over the years. |
Posted By: jimbo
Date Posted: August-30-2006 at 12:23am
| Hey, thanks 91 |
Posted By: john33617
Date Posted: August-30-2006 at 1:59pm
| never use SS bolts on exhaust manifolds , they expand at different rates and will break the manifold |
Posted By: 79nautique
Date Posted: August-30-2006 at 2:04pm
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Man you are just out there in lala land all of the time John maybe its all of them diesel fumes you inhail. ------------- http://www.correctcraftfan.com/diaries/details.asp?ID=756&sort=&pagenum=1&yrstart=1979&yrend=1979 - 79 nautique |
Posted By: rmcdonald
Date Posted: September-01-2006 at 3:07am
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Hi
Here is a good link discusses and gives a reference matrix for combining dissimmilar metals. It is mainly concerned constant under water exposure between dissimialar metals. http://www.estainlesssteel.com/corrosion.shtml - Stainless steel fasteners Regards Rob ------------- http://www.correctcraftfan.com/diaries/details.asp?ID=1177 - |
Posted By: jimbo
Date Posted: September-01-2006 at 11:36am
A good read. Thanks. Some people like to read Stephen King, some like Tom Clancy. I love reading that kinda of stuff 
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Posted By: Pete LHC
Date Posted: September-02-2006 at 1:17pm
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I just want to say thanks to everyone for their input...this is a great site.....
supported by great people. ------------- Thanks, Pete |