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Soon2BV

Floating Wedge Connector Bolt Size?

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Soon2BV

I (tried) to replace the bolts on my floating wedge today but couldn't get them installed. The bolts i was replacing are the ones at the top, that actually holt the wedge to the brackets.

I thought they were 1/2-20, but that size was very hard to thread in (the bolts actually thread into the brackets then slip through the wedge arms). I don't think they are 1/2-13 either.

Anyone have an idea or has anyone replaced these? The ones i removed were also very hard to remove - they came with the wedge when i bought it last summer.

I will try to contact Malibu next week, but thought someone here might know.

I may just need to run a tap through the brackets to clean the threads up.

The photo shows which bolt i am looking at.

wedge bracket.pdf

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Pistol Pete

I'm pretty sure they're 1/2-13

Can you take the bolt down to a hardware store and size it up on a thread gauge?

Plus, I sure hope Malibu didn't use stainless bolts into stainless brackets to stainless nuts. You know about this, right?

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Bawshogg

Ummmmm. They did. I had an early one that both of THOSE bolts broke off in the bracket.

New bracket and foil under warranty.

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Soon2BV

I'm pretty sure they're 1/2-13

Can you take the bolt down to a hardware store and size it up on a thread gauge?

Plus, I sure hope Malibu didn't use stainless bolts into stainless brackets to stainless nuts. You know about this, right?

I thought that was what i did, but i may have screwed up.

there are smaller bolts and nuts that are the stop point when the wedge is just hanging down, and they were 1/2-13 for sure.

The bolts i had for the top area (where I am having issues) were hardened, but not SS.

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Soon2BV

Plus, I sure hope Malibu didn't use stainless bolts into stainless brackets to stainless nuts. You know about this, right?

I read about using the same alloy of stainless can be an issue. What else are you referring to?

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Andrew63

My 2011 with factory floating wedge has 1/2" UNC (13 tpi) bolts.

Bolts are stainless with brass Nyloc Nuts.

Removed a bolt and matched it to a 1/2" UNC tap, perfect match.

Hope this helps.

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Soon2BV

My 2011 with factory floating wedge has 1/2" UNC (13 tpi) bolts.

Bolts are stainless with brass Nyloc Nuts.

Removed a bolt and matched it to a 1/2" UNC tap, perfect match.

Hope this helps.

great thanks.

that was the bolt at the top, that holds the "arm"? just want to be sure (boat is 4 hours away!)

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Pistol Pete

I read about using the same alloy of stainless can be an issue. What else are you referring to?

You're not supposed to bolt stainless to stainless, it can gall. Meaning, it will ruin the threads upon removal as if the threads were cross-threaded.

It sounds like you have this going on.

The way to prevent it is to add a lube like grease or anti seize to the threads although, I cannot confirm this is a permanent fix. It would seem to me the lube would wash out eventually considering the application.

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Soon2BV

i got a call back from Malibu. They said the thread is 1/2-20. And I checked and the bolts I removed are stainless.

I may switch to a grade 5 or grade 8 hardened bolt (not SS) and use some never-sieze or something on them.

I will probably try to run a tap through before i install.

I will update this after i get this done (a few weeks away) to "close the loop".

(I may also get some 1/2-13's and a tap just in case).

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Andrew63

Floating Wedge Top Pivot bolts are 1 1/2" long.

For the cost of the Bolts & Tap, your suggestion of picking up the UNC (13TPI) & UNF (20TPI) sounds like a good idea since the boat is 4 hours away.

May be best with a Tapered Tap.

You only have about an inch between the bolt & the rear of the hull so you will need some sort of Ratchet or low speed cordless drill to turn the tap.

Maybe an extension as I have the STE exhaust tips so I would need about a 4>5" extension to allow either a ratchet or drill to be square.

Remove the swim platform to make it a lot easier to see what you are doing, save hitting your head numerous times as well.

Not that I would wish this on anyone, but it may pay to also pick up a drill bit in case you have to drill out the existing bolt if it shears off.

Pilot drill a small hole about 1/8" or 3/16" & check how close to being on center you are with this hole.

13 tpi = 29/64 tapping drill or 0.4531" would be my choice as drilling by hand will create a slightly oversize hole if not spot on square

20 tpi - 15/32 tapping drill or 0.4688"

Google Stainless Thread Galling to learn more about Stainless Fastener issues.

http://www.google.com.au/url?sa=t&rct=j&q=&esrc=s&source=web&cd=4&sqi=2&ved=0CEMQFjAD&url=http%3A%2F%2Fwww.fastenal.com%2Fcontent%2Ffeds%2Fpdf%2FArticle%2520-%2520Galling.pdf&ei=Oo1VU-f_O8KbkAXgnICwCw&usg=AFQjCNGlXXBy5SI32yj3yIT7-0AtCeIlNw&bvm=bv.65058239,d.dGI

I suspect you will be in for a task if already Galled, may end up shearing the bolt off while trying to undo.

Not sure if any penetrating oil would assist.

No problem using Stainless fasteners, just use some anti seize or Grease at a pinch on the thread.

If/when it washes off, the galling occurs when the thread surfaces have pressure when tightening so loosening will not create a problem is not already galled.

Good luck.

A Trap for any AU members as we have the left over from the colony days & BSW is fairly common down here.

1/2" UNC is 13 tpi, Malibu's being US manufactured will use the UNC

1/2" BSW is 12tpi

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Soon2BV

OK, here is an update.

The upper bolts are 1/2-20 and the plate is threaded. I ended up using a hardened tap and cleaning up both sides. I removed some metal but it wasn't too bad.

Then i used never-sieze when i put the new bolts in. They went in pretty easy with the never-sieze.

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