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ThELiZ
23-08-2013, 07:19
Hi everyone,

I need some help with this one. I bought a brand new Jelco 750D last week, got it all set up but had to wait for a headshell to be sent to me as this was missing from the box. Anyway, it arrived yesterday, so all that was left to do was to install it and away I go! (it's worth mentioning that I have had a 750D before and had no problems setting up...)

Well, I could not figure for the love of God why the arm would not lower properly. I had to lower VTA so much that when I eventually got the stylus to hit the record, the VTA was at an extreme negative angle.

After much fiddling around, I eventually found out that the screw cap for the damping oil reservoir was causing the problem.

Here is the video... LGsUw0Vu71A

So, does anyone have any idea why this happens? I believe that there should be an O-ring on the cap, but have been told otherwise. I just remember that there was one on the last arm I owned. Maybe I'm going loopy.

Any help would be greatly appreciated.

surayne
25-08-2013, 11:34
If it's new, I'd send it straight back. Looks like a sticky bearing to me, but I'm happy to be corrected.

kininigin
25-08-2013, 13:02
I've just checked my arm and there is no o-ring on my damping cap!

Very strange what's happening with yours :scratch:

If it's new send it back!!

Johnnie7
26-08-2013, 11:54
i dont think you run the arm with the cap screw done tight down !!

if you unscrew the cap a turn or 2 i expect the arm works fine? and from memory i think you can put damping fluid in the bottom of the cap section?

might be worth checking the instruction manual on this point


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Ammonite Audio
26-08-2013, 12:10
My SA-750D is fine with the cap screwed all the way down.

mido
26-08-2013, 12:12
So is mine!!