I'm having the same problem Ed had back in 2008 with the Bilge blower. When I turn the key to "on" the blower starts running as normal. When I hit the interrupt button, not only does the blower continue running, the starter engages and keeps engaged! I changed the ignition switch with no change. Ed decided to simply bypass the timer and just use the manual blower switch. Meanwhile, I seem to recall that somebody came up with a batch of those timer tubes a while ago. I am assuming that the relays SE20/Se22 are no long available. Next step is to pull the caps off the relays and clean contacts but I think it is that tube since it never times out. Any left anywhere? - AZP
The issue with the starter staying engaged sounds like a stuck solenoid more than anything with the timer circuitry. The ignition switch could have caused the problem but since you've changed that out you can forget that. I think those relays might still be available somewhere but Gordon's doesn't have them. I think they were a general purpose automobile relays that I've seen on the firewalls of several old cars. Chances are you can fix up the ones on your car anyway. I've pulled the tops off of mine to paint them and while I had them apart I filed and cleaned the contacts as necessary. They are quite sturdy units and unless the coil fails I would think they would last forever.
I have some NOS timer tubes that I found some years ago. I think the original timer tube was a 2 minute delay but who the heck wants that. I have a few 20 second tubes that I will sell for $39 each. Let me know.
The starter works normally with the rear squash button. Let me contact you offline about a tube. It would probably be a good idea to have one for later if the problem turns out to be something else. As always, John, thank you. - AZP