Unformersatz EUa4 project

[me6_130]

Gentlemen,

I have recently bought an EUa4 as part of my Panzer item collection. Unfortunately it is in ground found condition. There is a chance of it being restaurable but I will need some advice, as I am rather the 'mechanical' kind more than 'electrical'. My intention is to dismount the electro engine-generator, clean it and see if it works. Any tips?

Carles

[cTapocTa]

As most of the paint is gone I would just thoroughly clean it and then re-paint.
CLR cleaner is outstanding for removing calcium and rust deposits. Use lots of penetrating oil (I recommend Ballistol) on "frozen" screws, give it a time. If its still not giving in, use "a la Yuri" method: apply soldering iron at full strength to the head of the screw for 3-5 min and then use proper screwdriver and pressure to unscrew it.
Don`t mess with the aluminum warning tag since its in a good shape, just clean it with Ballistol oil. If possible drill out the rivets and then re-attach after the cover is painted with steel/alu rivets and air hammer gun back on.

Good luck on your project and let us see you new EUa4 after its rebirth!

[me6_130]

Thanks cTapocTa,

I will surely remake all the paintwork. I have started early this year (Happy New Year to everyone). I am counting the time it takes me. I oiled all screws last night started dismounting the motor-generator this morning:


-The first thing I did was to remove all loose dirt, rust and paint with a toothbrush.
-I sharpened one of my old screwdrivers, as the slots of these german crews are very small.
-I reoiled the screws, cleaned the rust and retaining paint off around the screw heads and knocked all screws carefully 2 or 3 times, to loosen them a bit.

PS I will be shooting pics of all the process, so if anyone needs some extra, just let me know.

Carles

[Nick Komiya]

Carles,

If you wanted to have a working one, I can only say you should have avoided something so corroded inside. I personally think it is only suitable as a DEKO. For repainting after cleaning up I used to have RAL7021, Panzer Grey mixed, I also tried paint off Ebay, too, but last year, I found out that the standard 8 Euro can from my neighborhood home Improvement store, OBI was by far the best match. They sell it as RAL7016 and call it Anthrazitgrau. But shipping paint is always a big problem, so probably you need to find something local.

[me6_130]

Hello Nick,

I'm sure it would be easier to have a working one just buying it, but I enjoy much repairing things. It might end up as a deko but I do dare to dismount and repair this unexpensive one but wouldn't with one in fair condition. I won't loose anything, just enjoy doing it and, cross my fingers, hope it will work.

Thanks for the paint reference. I've got a pot of 'Panzergrey' but if the shade sould be different I will buy the correct one.

Carles

[Nick Komiya]

OK, I understand, but just take care, as you'll be dealing with high voltage. Panzergrey is fine, but some of the mixes are too blue to be authentic. I am emailing you on a different subject.

[Val]

me6_130, most problematic of all is getting motor/generator running smoothly again, looking at all the rust. You need definitely new bearings and both motor and generator must be balanced again. But here is advantage for you as you are more mechanical.

[me6_130]

Thanks Val,

I can imagine the transformer was up side down, and some water leaked in, about 2 cm at the front and dreceased to only touching the top of the M-G cover, so the rest is not so rusted. I opened the covers at both sides and oiled bearings to get them a bit soft before I dismount. Once cleaned I will see if they can be used again, if not replaced. Seems they are full of dry grease, so might be lucky.

Thanks Nick, I will have an 'electrical' guy testing the thing for me once done.


Carles

[Nick Komiya]

Here, to illustrate Val's point and aide you in your surgical efforts.

[me6_130]

Thanks a lot Nick!

I should have a web cam so you could just see how the work is doing.


I have released all screws and connections, except for one, that's welded. One of the sides is about to come off.
Carles

[Yuri D.]

I would have to say, just do what you're doing. Take it apart down to the basic components. Clean thoroughly. Then lubricate the ball bearings with thick grease. Make sure that the motor/generator can rotate freely by hand. Examine the brushes and brush mechanism. The brushes are mounted on bakelite brackets that precisely position them. It's important to take note of their original positions for proper functionality. Filter capacitors need to be replaced with new ones (by hiding them inside the old bodies). Open the capacitors (if possible) and use a heat gun to liquify the contents and empty them. The filter coils may be a real problem and need to be checked. Also you need to test the relay. After cleaning the relay contacts and making sure that it moves by hand, apply 12 Volts to the relay (center pin on the 5-pin connector for the + and ground for the -) and see if it works.

[me6_130]

Thanks Yuri!

I was wondering if the capacitors could still work or what to do if not, as I don't want it to look too modern. Great idea of hiding them inside the original containers. I take note of your advice, so I'll mark the exact position of the bakelite frame of the brushes.

Carles

[Yuri D.]

Also use a soldering iron to heat frozen screws. 5 minutes per screw. Attempt to unscrew immediately after heating.

[me6_130]

Yesterday's work:

-I managed to take the two side covers out. In one I dismounted the bearing, cleaned it and it is back to workin condition. I also dismounted the brusshes but the bakelite frame will need a bit more work.
-The other cover came out also but the bearing is stuck to the axel and brushes are stuck also, so more oiling and patience.
-Unfortunatelly the rotor is stuck (rusted) to the stator, so tomorrow I'll take it to a specialised workshop and ask if there is any chance of having it recovered...

Carles

[me6_130]

pics: