G250? Worth servicing?

[buddhasummer]

Woke up this morning IP hadn't gotten any higher but slight leak from one of the second stages. Just off to get a full tank. Will post back later.

 

[buddhasummer]

Ok, tuned the regs using a sound working 1st stage all seemed ok, but one of the second stages won't crack below 1.4" without leaking and even so still intermittently leaks. Hooked up to MK25 and machine was back, this happened with both G250 and known working XTX50. Removed Reg from 5th port and it won't machine gun.

I think I'll concede defeat and take the whole set to a shop, just hope SP service center don't have a fit because non standard parts....

 

[buddhasummer]

Took it into LDS, they hooked it up to a tank and told me the issue was with the 2nd stage, I told them it wasn't and that the problem manifests on any 2nd stage I attach and that when hooked up to a diff 1st stage there is no problem.

They kept saying the first stage was fine. They swapped out regs and the problem persisted. They then used an inline adjuster and adjusted orifice whilst pressurized without depressing the purge, I asked them not to do that. They then said it was because I was using the 5th port and should not. I said that was nonsense. They then said it was because I was using a long hose, again I said politely that that was nonsense. Regardless of what reg they used the priblrm persisted. I kept saying it's not the second stage it's the first.

Finally they removed the cap to look at the piston, ding ding, there is a very noticable flat edge on the piston as though it's been hit with a hammer. Problem identified. As this reg is brand new the fault was obviously at manufacturing. He said as I had no receipt as original purchaser he said SP would not fix it under warranty, nice one SP.

So I'm up for the cost of a piston. Price as yet unknown. They will ask and get back to me.

Bummer, but glad the fault has at last been identified. Bummed I have to pay for a manufacturing defect. I will never buy another new SP item, in fact no more SP period. I'll keep the G250s I have and go back to Apeks and diaphragm regs.

Thanks for all your help Bob. Cheers.

 

[rhwestfall]

Piston was $25 in the last catalog I saw in a shop (not sure the year it was). I got 2 off eB** last year for around that amount if I recall correctly. I was looking last week and saw one for sale (not in the US) for something like $50 (if it is the same between the MK-25 and the MK-25 EVO)

The "not original owner" to me is suspect.... I've even had recall items replaced free of charge on second hand equipment of theirs...

Glad the problem is finally diagnosed. Bummer to what it is, but have confidence in your rebuilding seconds.

Don't get all hung up on the 1.4" cracking effort. Give it time to settle in, re-tune, and you might be surprised. Then again, It just might be a stiffer spring than the others.

 

[Couv]

Wow, You guys have made a lot of progress since I last checked in. One big lesson learned here is even someone with little DIY experience can often sort out problems just as well-if not better than the local dive shop.

Contact ScubaPro (you might even try in their forum here on SB) and you may get some satisfaction. If not, I have a NOS piston I can make you a deal on.

Re the G250 with the high cracking pressure. The most likely candidates in this order: lp seat, orifice, spring. Is the orifice metal? If not, Bryan at VDH is having aftermarket orifices made which should be available soon. If the orifice is metal and needs attention, find posts by Zung, Halocline, and Rsingler on how to properly dress the edge.

Well done on your progress.

 

[buddhasummer]

Thanks guys for your support. I must say my experience at the LDS did little to improve my faith.

Re high cracking effort, I changed out LP seat twice to no avail. The s-wing poppet assembly including new spring were all replaced. I'll try another spring. Initially I used a new G250V orifice but it didn't play well with the lever height, it was way above the case rim and if it was inline it was way to low. I went back to the shorter brass orifice and it worked lever height wise, it "looked" ok but I will buy ne ones off Bryan to be sure and rebuild the Reg again. I'm using G250V diaphragms which look to be taller than the original, could this have an effect? If after doing all that cracking is still high I'll do as you suggest Bob and just let it settle a while.

I installed new G250V levers but may have stretched them fitting into barrel. Is there a trick to fitting them without stretching the legs?

I'll do as you suggest and reach out to SP on this forum re replacement piston but given I've never had a reply from either SP USA or SP Japan or my previous post on their forum I won't hold my breath but it's worth a try. I may well take you up on your kind offer Couv.

Given my very unlucky experience with piston regs can someone resssure me that they are worth sticking with. Depending on the cost of the piston it may be cheaper, almost, to buy a new DS4 out of Europe. In almost 10 years I've not had one issue with any Apeks regs I've owned, I trust them, as it stands I'm wary of piston regs.

Another big thanks to all who helped, I've learnt a lot, actually more than my10 years with Apeks. Because I've never had any issues servicing them, just followed the manual, I've never had to trouble shoot so have never really gained more in depth knowledge or understanding, working on these G250s has certainly done that. It would not have been possible without all the help I've received here, so an honest heart felt thanks.

I'll update once I get word from SP.

 

[Centrals]

I am glad I never ventured outside my comfort zone ie Apeks!!!!
DRIS had a special offer last weekend for a complete set of DST + 2 x TX 50 for US$299.00!!!

 

[halocline]

I've kind of late to the updates on this thread, but maybe I can offer something helpful. With regards to the MK25, if it creeps more than just a few (like 3-4) PSI with a new seat, it has to be the piston. I suspect if SP replaces your piston, you'll find that it locks up perfectly. I've only worked on a few MK25s, but they have all locked up absolutely perfectly with zero creep with a new seat.

With regards to the high cracking effort on the G250, it sounds like there's something up with the orifice. One other thing you might check is to make sure that the square holes in the air barrel that hold the lever are clean of any burrs and wear around the corners. Occasionally the lever feet can hang up a bit. Otherwise, if you have a new seat, new lever, and new spring, the only thing that can be causing the problem is the orifice. You might try setting the orifice without the diaphragm on, adjust it just until it stops leaking, then place the diaphragm on, put the cover on, and if it starts leaking, it should only take a slight adjustment. I guess there's a slight chance that diaphragm doesn't fit right.

Look on the bright side, you'll be an expert when you get this done!

 

[rhwestfall]

@JulesSCUBAPRO :

I know this is DIY, but there is a serious problem with a piece of equipment that the shop is ignoring.... hope you can read post # 183 above!

 

[rhwestfall]

You might try setting the orifice without the diaphragm on, adjust it just until it stops leaking, then place the diaphragm on, put the cover on, and if it starts leaking, it should only take a slight adjustment.

this is what I do too!