Purchased a Wallas 3000D diesel heater for a song and a dance a couple of days ago. Old model, been used in a boat. As everyone knows, electronics and the ocean breeze is a perfect combination, and of course the circuit board is in nothing but a perfect, 10/10 condition. As can be documented in the following pictures...

Just... perfect.

Needless to say, there are no schematics or component lists available. Or spares, for that matter So with all the conditions aligning so perfectly I decided to try to restore it. Naturally. What else could I do? Just write it off because it quite clearly isn't worth it?

Of course not. That'd be too... sane.

*Reaches for the happy pills*



Did I mention that everything has been soaked in a brittle compound that turns in to jelly when heated. But of course it is.
In the next picture I have already removed and tested the components, as well as cleaned most of the gunk off the bits in the lower right hand corner. I had to remove the two terminals, and the one with the pins... the pins were pitted and all the tin on it had just...vanished. Re-tinned them and put them back as I have no spares...



removed an IC and cleaned up the pads as best as could be done. Everything is through hole and the holes are tinned through as there are traces on both sides.



I found a few of these botches. Thankfully the LM324N is readily available, because shortly after this picture was taken one of the legs just fell off.

@Kai Robinson @Branchus If I may request some input from youse... how would one go about creating a schematic, layout etc. for this? I'm concerned about depopulating larger portions of the (or the whole) board and keeping track of all the components. Any of you guys have good work methods/software for this kind of thing I can shamelessly steal?

I'm depopulating the whole board, so that I can get some good pictures. I might try to recreate the pcb later on. Lots to learn here.

Marine CCAs are coated in a masking material to prevent damage from being exposed to salty/damp atmospheres.

>> KingDingus said:

Marine CCAs are coated in a masking material to prevent damage from being exposed to salty/damp atmospheres. Click to expand...

Welp.... didn't work all that well! :D I'm an outboard mechanic by trade so I'm familiar with most outboard engines and instruments and the protection measurements used there, but the goop on this board reminds me far more of the 80's cb radio goop that actually would become conductive over time and actively destroy the circuitry. Nevertheless, off it comes and I have to figure out what to use for protection if I ever make it work again. Remains to be seen.

I think I might put the board in a box of its own somewhere nice and dry. Like Nevada. ;)

Got around to a bunch of desoldering and cleaning just before and during easter... lots of nastiness

Cleaned up, as much as I can do anyway. I've pried, scraped, scrubbed... the silk screening started coming off so I had to call it quits at this stage:



Repaired a few broken traces, will have to do the rest when I repopulate the board. Some new resistors on order. There were a bunch of standing resistors originally, I will see if I can replace those with smd resistors (1206?) if I can attach them properly. Remains to be seen. So much solder mask to repair... Oh well. I better be able to make this work. I've put in about 40 hours of work so far :D

If you want to scan that in at 1200dpi, i'll happily create a sprint file for you :)

>> Kai Robinson said:

If you want to scan that in at 1200dpi, i'll happily create a sprint file for you Click to expand...

That would be great. I have a Canon printer/scanner here but the stupid thing refuses to let me scan while connected to my Airport Express... "No scan! Only print!" ... Maybe I can USB connect it to my PMG5 and scan using some old software from there :)

@Kai Robinson Just checking if you got my pm and could access the link?