Thanks David,
This is the best description of this process that I have ever had access to.
It was saved to my personal archives immediately.

Thanks

Jim Henry
Durham, NC
84 westy

-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
David Beierl
Sent: Friday, August 07, 2009 1:54 AM
To: vanagon@GERRY.VANAGON.COM
Subject: Re: 2.1l ECU - Solder Fatigue

At 01:08 AM 8/7/2009, Bob Stevens wrote:
>when you reflow do you just heat the "crack" area with a soldering iron?
>Add solder?

You always have to add at least a touch of 60/40 or 63/37 rosin-core solder
to the tip to get good thermal contact with the rest.  Easiest way is to
place (~20 ga or finer) next to the pin and then melt it with the iron so it
flows into the existing solder.  Make sure the joint is heated enough that
the lead can move.  Add a bit more solder if the existing stuff doesn't want
to melt freely and leave a smooth shiny joint.  Often helpful to do it from
both sides of the board if the lead is accessible from both sides.

This T-A board was not coated -- the Bosch ECUs I've seen (for 1.9l) have a
thickish clear coating to protect the board from moisture.  I've had
moderately good results simply soldering through the coating (but it gums up
the soldering tip so it needs a clean after every joint).  I've also seen
oxidation on component leads on Bosch boards, which prevents the solder
wetting the lead; so the solder has to be removed and the lead scraped clean
before resoldering.

The tip must be shiny-bright -- wipe it on a barely-damp cellulose sponge
before each joint and in between leave a drop of solder hanging from it.
Never scrub the tip on the board -- the copper foils have very little
adhesion when they're hot, so treat them very gently.

  --
David Beierl - Providence RI USA -- http://pws.prserv.net/synergy/Vanagon/
'89 Po' White Star "Scamp"