Jump to content
  • entries
    6
  • comments
    15
  • views
    826

Entries in this blog

New board is built and tested (and works!)

New board is built and tested (and works!)

Solid success today. Received the two new boards on Monday and built them today. Looks really good, the spade connectors are solid and tight, the components all fit.    Test fit:         Soldering it up:             Ran it in the test rig and works!    However still one more iteration. Sharp eyes will see where I had to enlarge one of the notches for it to fit the black plastic housing.

JsnPpp

JsnPpp

Cold start timer relay - board design done

Cold start timer relay - board design done

Took longer than I had hoped but I'm glad to report that v3 of the board design is complete. I had to modify the original design to support the new relay design (since the OEM is NLA), and then add a daughterboard to support the 6 spade connectors.   The photo shows the mockup of the board using paper. Its a decent way to sanity check measurements. I was off width by 1mm and height by 1 mm. Height isn't a big deal but width is since the board fits into the aluminum box.  

JsnPpp

JsnPpp

Walk through of cold start circuit (+ status of new boards)

Walk through of cold start circuit (+ status of new boards)

<TL:DR - the new board has been built and appears to work as designed! New post coming soon!>   I've learned a lot during this project. While the goal has always been to build a reproduction board, I also wanted to better understand the cold start circuit itself. Questions I wanted answered include: How do the components work together? What is the sequence of events? And eventually - is there room for modification?   I've found that the system behavior is different than

JsnPpp

JsnPpp

Building the test harness (woot! - it's built!)

Building the test harness (woot! - it's built!)

Progress on the test harness has moved faster than my blogging. ?   I'm excited - harness complete and used to test three OEM cold start timers. One works. The other two have peeling solder traces. Fixable but I won't spend time right now repairing them - once one spot is fixed its only time before another bit pops up.   Super interesting to see the behavior of the system. I'll document it so that folks know exactly what is happening when you turn the key. Have to say it's di

JsnPpp

JsnPpp

Examining the OEM Tii cold start circuit board

Examining the OEM Tii cold start circuit board

Prior to building a cold start relay I examined the two boards I have.   Both are out of '73's and are identical in general appearance.  By that I mean they appear to be the same circuit board schematic and all passive components are present. Here is the front and back of one of them:   However, the values of some resistors and transistors vary between the two boards. Could be several reasons for this - the system is much more forgiving than I realize and so it doesn't m

JsnPpp

JsnPpp

Initial thoughts on the Tii cold start timer box

Initial thoughts on the Tii cold start timer box

We've had two '73 Tiis for about 20 years. Neither car has working cold start timer boxes. Both have the manual cold start injector bypass button under the dashboard.   Both cars run well and always start. They have been without a timer box for so long I stopped thinking about it.     I originally considered about modernizing the timer circuit. Build it out of a micro-controller, a voltage regulator and a relay, jam it all in the box and call it good. However, a few years bac

JsnPpp

JsnPpp

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.