#342 Linkbox cracks

Posts about mechanical systems on a Telstar, including the outboard engine.
dcsailing1
Posts: 47
Joined: Sat Mar 21, 2009 8:01 pm
Location: Bandon, Oregon
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#342 Linkbox cracks

Post by dcsailing1 »

I sent the below email to Will last Mon night, 8/3. He hasn't gotten back to me yet and is out until Mon according to Sue. Good news is PCI and Will are busy and Tony is on the mend.
I thought the troops may have some insight or experience to help with what PCI comes up with as to cause and the best fix. Nine photos with original email but only 3 here:

> Hi Will: I spoke to you Mon. 8/3/09 AM re: problems closing both amas, in
> the water and not on the trailer, and cracks in the port ama forward linkbox.
> To give you more complete info:
> We bought this boat from Damon ----- in San Diego last year when there was
> going to be a delivery delay from PCI for a new one.
> We have always had some difficulty closing the amas in the water, never on
> the trailer. We recently launched the boat and found we were completely
> unable to close the port ama. While trying to close it by hauling in and
> back with lines we heard cracking and discovered the crack in these
> photos.
> It appears it goes through the second fastener out in the linkbox, next to
> an apparent factory cutout which is not found on the stb. linkbox and is
> widest at the outward end.
> If you follow the photos, the crack is almost invisible when the ama is
> fully open and gets more open as the ama closes. When at it's limit
> because of apparent interference with the hull, the crack is more then 1 inch as
> viewed from the bottom. It appears the crack is opening because of the
> twisting moment on the linkbox as the ama is driven down into the water
> from the angle of the outer pivit.
> If we weighted the ama with 500+lbs. there is no interference and the ama
> will now close and the crack stays closed.
> So we now know the why it won't close, but not the source of the crack.
> As I told you we are not aware of any hull damage and Damon reported none other
> then some "shipping" damage when he first received the boat. We did have
> to jam on the brakes last fall and the boat slid ahead causing minor gel
> damage from the V stop on the trailer to the bow.
>
> So our requests for help are:
>
> 1. Best way to repair this damage?
>
> 2. Best guess why it occurred in the first place and how to prevent a
> re-occurrence?
>
> 3. Why is the non-cracked stb. ama still difficult to close in the water,
> (feels kinda like the Port) but no visible cracks.
>
> I did measure the SS angular braces that appear they may be fitted and
> drilled/bolted as part of final assembly of hull/ama. The way I measured
> the stb. side is 3/8" shorter then the port. Is this normal tuning
> tolerance or could it be part of the problem with interference on the port
> side leading to the crack?
> Which came first, the chicken or the egg?

Comments and concerns welcome.
I believe the crack is from the twisting stress on the box as it tries to hold the ama down when closing and started at the saw cut stress point. The good news is, as Will first told me on the phone, the box is hardly needed when amas are open so the boat is still safe.
I suppose the fix will be to remove the box, open up to get access to inside for proper repair and replace.
trashpad

#342 Linkbox cracks

Post by trashpad »

The only times I have had problems moving the amas in or out came from the tramp tie slide. Salt tends to prevent the tram slides from moving freely which makes amas hard to stow. A lil spray silicon and my amas felt smooth as silk.
Last edited by trashpad on Fri Aug 07, 2009 5:23 pm, edited 1 time in total.
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