[R-390] Cleaning modules

[Roy Morgan]

At 08:19 PM 11/2/2007, you wrote:
>Simple Green?  Is it a common cleaning product?

Jon, and would-be Simple Green users,

Yes, it is a common cleaning product. And no, you really should not use 
Simple Green:

The Army aviation repair establishment published a maintenance note in 
their magazine oriented toward aircraft mechanics to the effect that Simple 
Green had been tested and shown to create corrosion in aluminum.

A couple of observations:
  - We may think we are rinsing well, but some of the cleaner may still be 
deep inside crevices and between parts that can't get a good flow of fresh 
water.
  - The modules in the R-390 are not Army helicopters and they certainly 
don't cost as much and are not depended upon to preserve the lives and 
limbs of people who use them

Sooo.. if you like Simple Green, go ahead.  Just let me know if I am 
tempted to buy one of your radios.

Restorers I know use a 50-50 mixture of 409 and household ammonia. The 
R-390/URR and R-390A/URR modules I cleaned not too long ago look new.

- apply with a squirter, brush vigorously with a paint brush, or parts brush.
- rinse well with lots of water
- dry with moderate heat (the summer sun in Arizona, or your oven at 120 
degrees - convection ovens work great!)  Heat lamps or just plain lamps 
placed close and a small fan will do.
- re-lubricate EVERYthing, and treat all switches with Caig De-Oxit (and 
pots with Caig MCL if they are not sealed shut).  Accept no substitutes, 
they have new names now, see www.caig.com for details and a trial kit of 
small tubes.

Remove all modules from your R-390x radio. Remove the RF deck and remove 
all the slug racks and transformers.  Wash everything as above. The meters 
are sealed so don't worry.  Your radio will look like new.

>  BTW, I'll make a note about the power thing.

Make sure you have a three wire line cord while you are at it.  Put in an 
inrush current limiter.

Roy




- Roy Morgan, K1LKY since 1959 - Keep 'em Glowing
13033 Downey Mill Road, Lovettsville, VA 20180
Phone 540-822-5911   Cell 301-928-7794
Work: Voice: 301-975-3254,  Fax: 301-975-6097
roy.morgan at nist.gov --