Momentary Relay?

I want to make a clutch cancel circuit for my Nissan Truck. I've already got it wired so that when I press a MOMENTARY Push button, it closes the clutch internlock circuit therefore doing the same thing as pushing the clutch in to start the truck.

I want to build a circuit that works similar to a Toyota Clutch Cancel Switch.

I will have a MOMENTARY push button that will send either a Postive or Negative to a relay that will close the Clutch Interlock circuit for a set amount of time.

Is there a relay that can be purchased that will close for a set amount of time (5-10 seconds?) or will this circuit work as described in this diagram work?

https://www.the12volt.com/relays/page5.asp#pts

If so, how do I adjust the amount of time that it stays closed.

Use a 555 timer IC (e.g. LM555 by National Semi-conductor www.national.com, search for LM555, download and view the datasheet) to drive the low-current coil on your relay.  The 555 timer chip is fairly precise and can be adjusted with a resistor and a capacitor.  You would be interested in the monostable circuit example given in the datasheet.  Use your momentary switch (or other "trigger") tied to the trigger pin on the IC, then let it run it's output for the duration you calculate/want.  Technically speaking, the output is "high" (Normally Open, sort of, in relay-speak) for the set period of time, but there is another way to tie into the circuit to get the opposite "low" (Normally Closed, again, sort of, in relay-speak).  Here's a useful link on the chip and examples, etc.  Interesing that the same site but different page was posted by another person to your question: http://ourworld.compuserve.com/homepages/Bill_Bowden/555.htm

 The first (left-most) image of the circuit on that link that shows Monostable, or "one-shot", would seem to be your best bet.

HTH

--HC