The big flap Push/Pull

I cant find any previous Building Threads post so I have started a new one.
In the "Cafe" 2 days ago I mentioned that due to the bad weather I was repairing several planes including the Push/Pull which I thought had a servo problem, however after some testing I discovered the problem was not one servo but all of them! 
This video shows the problem - servo jitter.
.
You really need to use full screen to see the effect.
As it effects all 5 servos but only when the motors are running I have to assume the problem actually lies with the ESC.
This plane was built in May 2012 and nothing "electrical" has be replaced since then and that includes its odd 2S2P 2200mAh LiPo still with its original box!
 
The ESC is completely "built in" so will have to be cut out to be replaced. The only problem is I have forgotten exactly where it is.
 
 

I had forgotten just 'how sardine can' I had made the Push/Pull'
the ESCs are just behind the pylon "spar"
 
They are both in there - honest.
 
Just to make thing a bit more difficult the both ESC are Y lead but actually joined (soldered) in the servo plug.
The Rx is just ahead of the pylon spar and accessed from the other side.
 
Note it is 35 meg!
To stand any chance of actually getting either or both of the ESCs out I also need access to the motor wire soldered joints.
 
Having found out where all the bits are I now have the tricky job of actually getting the ESCs out
Hopefully before I actually do that I can arrange drive the ESCs from an independently powered servo tester to check if the control surface servos driven from the Rx still jitter.

Finally the flaps are tape hinged which after 12 years are suffering a bit so as I now I have a 3D printer I will make some proper pin hinges for them.  

I managed to extract the ESCs without doing too much damage.
 
The object being to be able to test them on another motor and to test the original motors using another ESC .
The results were a bit confusing.
Both ESCs ran a slightly larger version of the same motor but no prop without any problem.
Both motors ran OK with a bigger ESC. One motor occasionally stopped and screeched when close to full power..
BUT
Neither motor ran at all well with either of the original ESCs reconnected.
When both original motors and original ESCs were connected either one or both of the motors just oscillated.
This rather suggests that the original ESCs (there is no amp markings on them!) are basically inadequate particularly when the big starting pulse causes a voltage drop that upsets the other one.
In hindsight the Push/Pull always needed a couple of goes before both motor started to run on launch. Once in the air the props wind milled so restarting was never a problem.
On this basis I fear both the ESCs and motors will have to be replaced.
Some time with Google is required.