OK, the plot thickens...

thanks everyone for all your help so far. I have tested the BRs and all the resistors and capacitors on the power board. I have replaced the old capisitors and I can say that the BRs are all in tact.

I replaced the offending fuse and tested the board thouroguht at each TP. NO PROBLEMS!

I connected the board up, swithced on the game and it completed its reset cycle, meanwhile the bumpers locked down again, Then, the same fuse blew. Then... you ready for this???? a Darlington Transistor was blown off the solenoid driver board, and I do mean 'blown off', it landed on the playfield.

Now I have a new dilemna. According to the schematic these are 'TIP122 100V 8A'. Looked on a few websites and it turns out that TIP122 are 100V 5A and that 100V 8A are TIP102. I cannot find TIP122-100-a anywhere. IS this 'TIP' number significant? it seems I cannot match the complete part number.

Thanks everyone,
Sandro.