Halcyon H75P + Halo (weird?) cranking effort

[Open Ocean Diver]

Is your orifice adjusted just to stop the valve leaking?

 

[Nemrod]

When using the Magnehelic gently apply suction until the needle rises and then drops, that is the cracking force value. But, from that video those regulators are considerably out of specification. Assuming that the seat is new and undamaged (by turning the orifice without pressing the lever down) turn the adjustment knob fully out and then adjust the orifice inward (back it out first) until the regulator just barely stops flowing, just barely. Then cycle the regulator or let it sit overnight. It will probably free flow with the knob fully out after the seat takes a set. You might then turn the orifice inward a tiny bit, 1/16 turn at a time, until it stops flowing. Some like to let the regulator just barely flow when the knob is fully out.

 

[estresao]

Is your orifice adjusted just to stop the valve leaking?

Yes, they are.

 

[estresao]

When using the Magnehelic gently apply suction until the needle rises and then drops, that is the cracking force value. But, from that video those regulators are considerably out of specification. Assuming that the seat is new and undamaged (by turning the orifice without pressing the lever down) turn the adjustment knob fully out and then adjust the orifice inward (back it out first) until the regulator just barely stops flowing, just barely. Then cycle the regulator or let it sit overnight. It will probably free flow with the knob fully out after the seat takes a set. You might then turn the orifice inward a tiny bit, 1/16 turn at a time, until it stops flowing. Some like to let the regulator just barely flow when the knob is fully out.

That happened, but today I adjustded them again. Last time I adjusted the orifice in both until they barely stopped free flowing and, in my last dive I had to close a little the knob to stop free flowing in water. At this point the Magnehelic read very similar values, being one of the regs harder than the other.

One thing it could be related is the maintenance kit is not original, but from Scuba Gaskets. Or maybe I didn't lubricated them properly?

 

[Nemrod]

That happened, but today I adjustded them again. Last time I adjusted the orifice in both until they barely stopped free flowing and, in my last dive I had to close a little the knob to stop free flowing in water. At this point the Magnehelic read very similar values, being one of the regs harder than the other.

One thing it could be related is the maintenance kit is not original, but from Scuba Gaskets. Or maybe I didn't lubricated them properly?

Is the poppet spring in the second stage original or did you replace it? Is the poppet original or has it been replaced? Did the springs or parts get mixed up between the regulators? Has the balance chamber been replaced?

Some springs are longer, shorter, stiffer etc. Some balance chambers have a longer body putting more pressure on the poppet spring.

Something is not adding up here.

James

 

[estresao]

Is the poppet spring in the second stage original or did you replace it? Is the poppet original or has it been replaced? Did the springs or parts get mixed up between the regulators? Has the balance chamber been replaced?

Some springs are longer, shorter, stiffer etc. Some balance chambers have a longer body putting more pressure on the poppet spring.

Something is not adding up here.

James

Hi,

Poppets and springs are originals and not mixed. Only replaces the poppet seat and o-rings. I took lot of care removing the levers to avoid them getting bended, but it was not easy to remove and replace them.

All metallic parts were cleaned using ultrasounds

 

[Nemrod]

Hmmmm. Well, double hmmmmm. The reason you have the two stage inhalation is because the cracking force appears to be over three inches. Thus when the Venturi finally kicks in enough to assist your inhalation demand you feel a sudden increase in flow and decrease in effort. You are not going to get beyond this problem and have a smooth breathing regulator and a smooth transition to Venturi assist until you figure out why you have a cracking effort way over specification? Maybe @buddhasummer can help?

Am I really seeing a cracking force measuring over 3 inches of water, basically twice specification?

 

[estresao]

Hmmmm. Well, double hmmmmm. The reason you have the two stage inhalation is because the cracking force appears to be over three inches. Thus when the Venturi finally kicks in enough to assist your inhalation demand you feel a sudden increase in flow and decrease in effort. You are not going to get beyond this problem and have a smooth breathing regulator and a smooth transition to Venturi assist until you figure out why you have a cracking effort way over specification? Maybe @buddhasummer can help?

Am I really seeing a cracking force measuring over 3 inches of water, basically twice specification?

It makes sense. Meantime I'm planing to re-overhaul them and double check they're properly lubricated and whether levers are OK. I'll compare springs sizes just in case they have been shrunk or stretched.

 

[Nemrod]

Just to be clear, those second stages should crack around 1.0 to 1.4 inches for best performance. Anything outside of that is not acceptable and 3.0+ inches is not only not acceptable but potentially dangerous. Cracking force is not affected by the Venturi assist lever just to be clear on that also.

If you have the original O-rings removed from the poppet stem that inserts into the balance chamber, could you compare them to the ones now installed?

 

[estresao]

Just to be clear, those second stages should crack around 1.0 to 1.4 inches for best performance. Anything outside of that is not acceptable and 3.0+ inches is not only not acceptable but potentially dangerous. Cracking force is not affected by the Venturi assist lever just to be clear on that also.

If you have the original O-rings removed from the poppet stem that inserts into the balance chamber, could you compare them to the ones now installed?

I'm not pretty sure I saved them, but I'll check that up. But I remember I've compared them when replacing and didn't see differences (at least to my eyes)

I"ll try to get a couple of original maintenance kits... just in case.