Hand wheel resistance

[in too deep]

OMS manifold hand wheels are very difficult to open and close, other than when the tanks are pretty much empty. I’ve compared to other divers manifolds (different brands) and theirs work very well.
I’ve seen videos of valve drills where the diver effortlessly can close and open any of the hand wheels.
It was purchased recently. I’ve booked it to go into the shop on Thursday but I’m prepared for “nothing is wrong”. Anyone have/had the same issue and what did it take to solve. Rebuild or adjustment?

 

[michael-fisch]

Clean everything with a toothbrush using the most aggressive degreaser that you can get (I use Nitro Solvent) and then finish the cleaning in a heated ultrasonic bath.
When you reassemble with new o-rings you'll have to make a hard decision, if you lubricate with O2 compatible lubricants you'll never have really easily turning knobs. I use only silicione grease (not O2 Compatible, but it has been working well for me since I started using it back in 1994 for my OC gear which is usually filled to 250Bar), open the valves slowly, and either remove or massively shorten the spring in the handwheel. This results in being able to open and close the valves using the palm of my hand without having to grab anything with my fingers. The silicone grease has no business being anywhere near the sealing surface on the valve lower spindle and should only be used sparingly on the lower spindle threads! Unfortunatly my experience with Christolube and other O2 compatible lubricants has not been good, after around 6 months they work like coarse rubbing compound and are a pain in the a**.

Michael

 

[in too deep]

Clean everything with a toothbrush using the most aggressive degreaser that you can get (I use Nitro Solvent) and then finish the cleaning in a heated ultrasonic bath.
When you reassemble with new o-rings you'll have to make a hard decision, if you lubricate with O2 compatible lubricants you'll never have really easily turning knobs. I use only silicione grease (not O2 Compatible, but it has been working well for me since I started using it back in 1994 for my OC gear which is usually filled to 250Bar), open the valves slowly, and either remove or massively shorten the spring in the handwheel. This results in being able to open and close the valves using the palm of my hand without having to grab anything with my fingers. The silicone grease has no business being anywhere near the sealing surface on the valve lower spindle and should only be used sparingly on the lower spindle threads! Unfortunatly my experience with Christolube and other O2 compatible lubricants has not been good, after around 6 months they work like coarse rubbing compound and are a pain in the a**.

Michael

Michael,

Thank you for the very detailed reply.
I'll bring this with me to the shop on Thursday for their review.

 

[Lorenzoid]

My brand-new Dive Gear Express manifold valves were difficult to turn. When I started learning valve drills, I replaced the DGX with a Thermo manifold. Valves turn like butter. Your issue COULD be a service issue, but it also could be that some brands are harder to turn than others.

 

[in too deep]

My brand-new Dive Gear Express manifold valves were difficult to turn. When I started learning valve drills, I replaced the DGX with a Thermo manifold. Valves turn like butter. Your issue COULD be a service issue, but it also could be that some brands are harder to turn than others.

I'll send an email to OMS, was on their site and did not see manifolds anymore...maybe that's why they don't sell theirs anymore.

 

[michael-fisch]

Michael,

Thank you for the very detailed reply.
I'll bring this with me to the shop on Thursday for their review.

The only response you will get from your shop is that they MUST use O2 compatible lubricants, which will not help you with your problem. Disassembling and reassembling a manifold is not rocket science, anybody who can walk and chew gum at the same time should be able to do it.

Michael

 

[in too deep]

The only response you will get from your shop is that they MUST use O2 compatible lubricants, which will not help you with your problem. Disassembling and reassembling a manifold is not rocket science, anybody who can walk and chew gum at the same time should be able to do it.

Michael

lol. I'll keep this reply as the ace up my sleeve. I'd do it but it's under warranty and they should be able to do as you suggest. Thanks again!

 

[rjack321]

OMS never really "made" manifolds they put their brand on stuff they imported.

They need to be rebuilt and properly greased. Its also possible the valve stems have been bent (but unlikely all 3 at once). Or the stems are corroded and crusty in the bonnet nuts.

If you do it yourself you'll 1) only buy and pay for the parts you need 2) know its don't right not by some monkey

You for sure need:
3 crush washers (~$5)
3 stem orings ($1)

You may need:
Teflon packing washers ($15)
HP seats ($45)
1 to 3 valve stems ($35)

Personally I would never have a shop rebuild a valve. (or manifold)

 

[Lorenzoid]

@rjack321 , have you heard of some manufacturers' valves inherently being harder to turn than others? As I mentioned above, the valves on the brand-new DGX manifold I installed were difficult to turn, so I eventually replaced them with Thermo, which turned easily. I later read of someone else having had the same experience with DGX manifolds.

 

[rjack321]

@rjack321 , have you heard of some manufacturers' valves inherently being harder to turn than others? As I mentioned above, the valves on the brand-new DGX manifold I installed were difficult to turn, so I eventually replaced them with Thermo, which turned easily. I later read of someone else having had the same experience with DGX manifolds.

I have a whole ton of DGX valves. They all turn smoothly for me.

The pitch of the HP seat threads can influence how easy they are to turn. But lubing them properly is a bigger factor. Thankfully the DGX valves don't have crush washers so its easy to pop the bonnet nut off and lube the threads on the HP seats. I haven't had to do that on mine (yet)