186 Hydro

Starting from empty, the bottom sender causes the gauge to move to about 1/2 tank. The resistance of the lower sender then remains constant, and, as the upper tank begines to fill, the float in that tank begins to rise and the sender unit in that tank begines to change resistance, causing the gauge to begin moving upward from 1/2 towards full.

The sender with one insulated terminal needs it's metal frame grounded for the system to work, and both floats must be intact, and free to move, and both senders need to have electrical continuity that changes with float position, for the system to work.

I do not have an IH manual for this, but the local town uses one of these tractors for maintenance, and we service it. They have the IH manual, and the gauge circuit is spelled out in detail. I would recommend having the manual at hand, or see if the dealer will copy the pages pertaining to the fuel gauge.

Hope this helps
John

John

I've never worked on your model of tractor per se, but usually in a fuel gauge circuit, that pegged "full" needle means that there is an open circuit somewhere on the meter side of the gauge to the sender(s).

Likewise, a pegged "empty" needle would indicate a short to ground in the fuel tank wire(s).

If you don't have to switch a "tank select switch" between the two tanks, then I can't imagine there being two senders. Is there an equlizer line running between the two?

Hope ya get 'er going,

Allan

John

I'll finish the wood work today and then start in on the varnishing.....Then, I'll put a picture up and let you guys laugh me out of the country!

A carpenter I just am not. :>)

However, I'm a musician and the wife is strongly urging me to take my guitar and all it's assorted support equipment out of her living room and place it squarely in the new "den". Ha.

Thanks for the holler,

Allan