Question Crotch strap for a jacket BC

[thesaltyfins]

Hello
Can we retrofit a crotch strap on regular jacket BC? In my case its the Aqualung Zuma BC. Offlate my bc starts squishing as the dive progresses and eventually by the end of the dive the waist band is almost touching my rib cage.
The waist band sits in place when the bc is inflated but as soon as i deflate and descend, within few minutes it is all over my torso. The only way i could keep it down is by holding it with both the hands. I have tried adjusting the bands as much as possible but no use.
So now only thing that i can think of is putting a crotch strap. But how?
Has anyone done or succeeded in doing this?
Is it advisable ? any hazards?

Or backplate/wing is the only solution to this!!?

Thanks

 

[Jcp2]

Is there something for a crotch strap to loop into on the bottom rear of the bcd? The front usually attached via the waist strap.

 

[thesaltyfins]

Thanks for writing
Nope. There is nothing at the bottom end on the rear.

This is how it is from rear.

 

[BoltSnap]

Is there something for a crotch strap to loop into on the bottom rear of the bcd? The front usually attached via the waist strap.

^^^^^^^
This

 

[BoltSnap]

Thanks for writing
Nope. There is nothing at the bottom end on the rear.

This is how it is from rear.

View attachment 756753

Is there a hard backpack behind your back?

 

[Bowers]

Ive run a piece of bungee from a tiny d’ring in the back to a loop over the strap in the front. Worked fine but i doubt it would be comfortable in a really thin wetsuit

 

[rx7diver]

Can we retrofit a crotch strap on regular jacket BC? ...

@thesaltyfins,

I know nothing about the Aqualung Zuma BC, but In the case of my old Scubapro Classic Stabilizing Jacket BC (which has a plastic backpack bolted onto it), there is a slot molded into the bottom of the backpack through which a crotch strap can be attached.

But, I have never felt the need to use a crotch strap with my Stab Jacket (when diving a single tank).

I wonder if your Zuma is fitting you correctly. Could it be too large for you? If so, and especially if you are diving a very thick wetsuit (which crushes down with depth) and carrying much more Pb than you actually require, then the problems you describe can certainly manifest, I think.

rx7diver

 

[thesaltyfins]

Is there a hard backpack behind your back?

No

 

[thesaltyfins]

@thesaltyfins,

I know nothing about the Aqualung Zuma BC, but In the case of my old Scubapro Classic Stabilizing Jacket BC (which has a plastic backpack bolted onto it), there is a slot molded into the bottom of the backpack through which a crotch strap can be attached.

But, I have never felt the need to use a crotch strap with my Stab Jacket (when diving a single tank).

I wonder if your Zuma is fitting you correctly. Could it be too large for you? If so, and especially if you are diving a very thick wetsuit (which crushes down with depth) and carrying much more Pb than you actually require, then the problems you describe can certainly manifest.

rx7diver

Thanks for the input

Wetsuit: 2mm

Fit is correct as per the size chart(M/L for my height-179cms) and have been using it since 2017. But post 2017 i have lost weight.

Weight used: Max 5lbs

 

[thesaltyfins]

Ive run a piece of bungee from a tiny d’ring in the back to a loop over the strap in the front. Worked fine but i doubt it would be comfortable in a really thin wetsuit

I use a 2mm wetsuit, so just a bungee cord would be uncomfortable.

Thanks