• To ALL forum users - As of late I have been getting quite a few private messages with questions about build ups here on the forum, or tech questions about your personal project. While I appreciate the interest, sending me a private message about these topics distracts from, and undermines the purpose of having a forum here. During the day I wear many hats as a small business owner-operator and I work tirelessly to provide the absolute best service possible to you, our valued customer. When I created this forum I rounded up some of the best minds I knew so that any tech question you might have could be asked and answered by either myself or one of my highly experienced moderators, this way the next time this same question is asked the answer can be easily found and utilized by the next IH enthusiast having the same question. This allows me the freedom to run the day to day operations of the business and minimize the impact to shipments and shop activities that these distractions can cause. It is of the up most importance for me to complete the daily tasks in order to best take care of you our customer, all the while providing you a forum to get the level advice and input you have come to expect and deserve from the premier IH shop in the country.

    So with that I ask that anyone with a question about one of our build ups or a general tech question to please use the forum as it was intended. I am absolutely available by telephone to answer your questions as well but at times may direct you back to our website to better field your question or questions. Most other private messages I will be glad to answer for you.

    Thank you for your understanding.

    Jeff Ismail

1971 International 1110 Pickup


New member
Hello everybody.

I have a 71 1110 that I've been working on as a project for the past couple weeks. Needs a lot of work. But there are a few things I'm stuck on. First is the ignition switch. See picture below:

key switch.jpg

This is the ignition switch for the truck. It's dead. I bought a universal 4 terminal replacement, but am having a bit of trouble. As you can see there are a lot more wires here than 4. Do any of you have a wiring diagram for this so I know what goes where? On to the next issue... I also heard that there's a main power relay along with a module that controls the instrument cluster behind the dash (a bit skeptical on this one, it seems a bit complicated for a 70s model truck), but wanted to know if anyone has heard of this or where I'd get a replacement. There are several things not getting power. The instrument cluster is especially important.

Thanks in advance for any help!


Now that you know what you need to properly replace the switch, what diagnostics did you perform to arrive at the conclusion that the switch is dead? I think what you might be referring to in terms of the OIL TEMP & FUEL instruments is a little device called a Constant Voltage Regulator, or CVR for short. It is not a relay. What it does is reduce the battery voltage to an average of about 5 volts, which is what those three gauges require as input power. Full voltage will fry them in short order. If even one of those three gauges is functioning properly, then the CVR is doing it's job. If all three are in-op, then the CVR is a leading suspect, but not the only possible cause.