Apeks ATX200 1st stage; Can't get cap off with Pin Spanner

[ocalld]

Hi
My Apeks ATX 200 is in need of a service.
I've got the end cap off with the pin spanner without any problems.
But, i can't get the second cap off with the pin spanner.

I've tried hot water.

Can anyone advice how to get this stubborn cap off without damage?

Cheers
Dan

 

[j2s]

Have you tried soaking in bottled water for about 5-7 days, changing the water each day ???....The manual for the DS4 and DST recommends soaking parts in houshold dish soap to clean parts...I used that to loosen both caps on a stubborn DST w/two spanners, a hex bar and a vice.....Sounds like someone over-torqued the caps on yours as they did on mine.......

 

[ocalld]

Thanks for the info, i'll try that next.
At the moment i've got it in the freezer, when it's nice and cold, i'm going to try putting the cap, up to the threads in hot water to see if that will free it.

after that, i'll try the soaking.

Thanks
Dan.

 

[j2s]

Thanks for the info, i'll try that next.
At the moment i've got it in the freezer, when it's nice and cold, i'm going to try putting the cap, up to the threads in hot water to see if that will free it.

after that, i'll try the soaking.

Thanks
Dan.

You may want to consult w/someone about what the sudden temerature changes might do to the metal....I've never heard of that being done....If that's feasible, hope it works and let me know...Be good for future reference.....

 

[Zung]

It is feasible.
I did it to a couple of particularly stubborn Scubapro MK10's without any dire consequence: freezer, then hot water, repeat.
Even though most plastics are rated to above 100°C, I replaced all o-rings after the treatment just for peace of mind.

 

[j2s]

It is feasible.
I did it to a couple of particularly stubborn Scubapro MK10's without any dire consequence: freezer, then hot water, repeat.
Even though most plastics are rated to above 100°C, I replaced all o-rings after the treatment just for peace of mind.

Thanks Zung, Always good to learn new tricks that'll make life easier.....

 

[nwbrewer]

This happened to me on a DST. I threw the whole thing in the ultrasonic cleaner for a while, then put it on a reg tool and clamped it up. Had to smack the pin spanner a few times, but it finally broke loose.

 

[ocalld]

just an update:

freezing several times didn't help.
i tried the ultrasonic bath, still no help.
I resorted to hitting the peg spanner with a hammer to try and shock it, that just rounded the brass around the hole. Doh!!

Well i was pretty desperate now, so thought what that hell, if i damage it any more i'll just have to replace it, so i took a pair of mole-grips to it and it came off with ease and hardly left a mark!!!

I think the problem was that when it was assembled last, i used christolube. Christolube liquid separates from the grease over time and leaves a chalky substance that holds threads tight. any one know of a better O2 grease to use?

BTW, The hex nut on the bottom of the 1st stage (H.P. Balance plug, part 18 in the service manual) was very stuck.
Had to soak the 1st stage in penetrating oil over night. Then drill two small holes in the plug to fit a peg spanner. The secret here is to drill right through the plug until you hit the air gap, otherwise the peg spanner won't go in far enough and will snap off when you try to undo (yes, i did that too), you need to ensure the pegs go right in. Put a hex socket in the plug, hit with hammer to shock threads then undo with peg spanner.

Reg now working perfectly, just needed a service kit and new H.P. Balance plug.