Through hull flange adapter and groco ibv 750 thread reassuring

[Eastward ho 24]

I had a pretty extensive thread last week about thru hulls Seacock and flange adapters. I decided to go with the bronze mushroom through hull grocco flange adapter and the groco ibv750 ball valves. My understanding is the flange adapter accepts the straight thread from the through hull which threads in all the way and seems right. However the flange adapter is supposed to be male npt and the valve is supposed to be female not. When I screw the valve in I olny get 4 full turns. It goes in snugs up but there's still plenty of room to thread in further. Is this right? I'm not even getting half of the threads into the ball valve. Doesn't seem right. The last pic with my finger shows how deep the threads are going Here'spics...btw I got 1/2 g10 to use as backing plates.holy cow some serious stuff!

[Eastward ho 24]

Pics. The thread comparison is the one on the left is NPS ( the through hull) the left npt ( flange adapter)

[motion30]

You get 4 threads engagement eating it by hand? That seems about right to me

[Eastward ho 24]

Yes by hand tight.. dope it and put the wrench on it should be good?

[Saltyhog]

Once you get some pipe dope / Teflon tape (I use both) on them and tighten them up with pipe wrenches, you get a lot more thread engagement. I think you're fine.

[Eastward ho 24]

Ok thanks

[VSalcedo]

You may want to take a look on the installation manual:
https://www.groco.net/distributor-tools/service-manuals

Regards,

VictorS

[deblen]

thru hull x NPT valve.PNG Views: 162 Size: 141.0 KB ID: 160931" style="margin: 2px" />

Above pic is the wrong way to use a thru hull/skin fitting.
Straight thread into a taper thread valve.

Seacock & Thru-Hull Primer/Pre Information Photo Gallery by Compass Marine How To at pbase.com


Len

[mitiempo]

Originally Posted by deblen

Attachment 160931

Above pic is the wrong way to use a thru hull/skin fitting.
Straight thread into a taper thread valve.

Seacock & Thru-Hull Primer/Pre Information Photo Gallery by Compass Marine How To at pbase.com


Len

True, but that is not what Eastward is doing.

Npt threads will progressively tighten - they are supposed to. With a wrench you should be able to turn the valve the rest of the way or almost. Use thread sealant or teflon tape.

[GordMay]

Greetings and welcome aboard the CF, Victor.

[Eastward ho 24]

Thanks everyone. Just seems off since the straight threads go right into the npt valve. and npt to npt doesn’t seem like it works but that’s the taper tightening.

[rgleason]

These groco ibv valves are pretty good, but there is a lot of fitting and planning if you want your valve handles located in a certain orientaion. I threaded them on tight with a pipe wrench and teflon, marked the triangle base orientation on the hull, anticipating a little extra turn, and then unscrewd the ibv valve for further fitting of the backing plate and thruhull. Do them one at a time, you'll get better at it.

[Eastward ho 24]

I will. I also opted out of using the 1/2" g10 , I ordered some of the bb backing blocks from groco once I realized how much torque I'd need to tighten them properly. Seems it'll make life easier, I just hope the block will over lap the old holes where they were through bolted from the outside.