Riser studs

rebars1

Senior Chief Petty Officer
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Feb 23, 2004
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744
Is there any recommendation for installing the riser studs to the manifolds (grease,loc-tight,dry)? Also, for the nuts. Merc 888, 1971, Ford 302. My manual (Clymer) says the torque should be 25 ftlb.
 

Don S

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Aug 31, 2004
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Re: Riser studs

I use Mercruiser Perfect Seal on the bolt threads, it prevents the threads from rusting.<br />The studs should be torqued to 27 ft. lbs., the nuts will then be torqued to 25.<br />If you have Mercruiser manifolds/risers, the gasket is installed dry.
 

Don Brock

Cadet
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Aug 5, 2003
Messages
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Re: Riser studs

I've been curious - why not use bolts on the risers instead of studs and nuts? It would be a lot easier to remove the risers if I didnt have to raise them off of studs. Besides I had to remove the studs before I could get my risers off due to a lack of overhead clearance. And of course there is no unthreaded part visible to get ahold of so I have to use plyers on the threads. I really wanted to put them back with SS bolts, but I figured there was some reason Merc used studs, so I replaced them with new studs.
 

rebars1

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Feb 23, 2004
Messages
744
Re: Riser studs

I was thinking just the opposite when I was installing my manifolds! It would have been a lot easier to slide them onto studs than it was to hold them and the gasket in position to install that first bolt.
 

Darrendude

Petty Officer 2nd Class
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Nov 16, 2004
Messages
145
Re: Riser studs

My merc has bolts on the riser and studs on the manifold. I am thinking of puttind studs in for the riser. I would think it is easier to brake off a bolt opposed to a stud.
 

trog100

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Dec 1, 2004
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Re: Riser studs

another one of those "which is best topics".. he he<br /><br />over the years i have noticed a tendancy for manufacturers to use bolts where previously they would have used studs and nuts..<br /><br />i always put it down to saving time and money during manufacture.. easier for the robot to wang em in.. on this logic studs would be the better method.. bolts the cheaper one..<br /><br />if something has to come apart on a regular basis i think studs are less prone to breaking off in the block or stripping the threads in the block.. studs tend to strip threads at the nut end sooner than break off.. they do need more clearance to get things off thow..<br /><br />trog100<br /><br />ps.. mind u when there aint enough clearance to get soemthing off and having to get plyers on the studs to remove them first.. definitely makes a strong case for replacing them with bolts.. he he
 

yoced

Petty Officer 2nd Class
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Oct 8, 2003
Messages
142
Re: Riser studs

from the manufacturing side, yes the bolts are cheaper. Until you get into weird sizes, when it becomes cheaper to use studs if you have the capability to make them correctly.<br /><br />One less important but reinforcing reason to use bolts more often is 'the lowest common denominator'. Almost any idiot can put a bolt in correctly. More of those same idiots will fail to put studs in correctly. Simply put, manufacturers tend to try to idiot-proof the parts as often as possible. When that route is cheaper as well, they will most assuredly go that way.
 
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