High Idle/Cold Advance Question

Does anyone know at what water temp the high idle and cold advance are supposed to kick off?

Currently mine shuts off at about 130F. As the truck gets closer to temp it’s starts to sound likes it’s gonna run away . It a slow crescendo where it gets really loud and fast and when it shuts off it’s like it drops off a cliff and almost makes you think it stalled but just gets quiet and slower.

I wish it would kick off a lot sooner before it gets this loud.

At what temp does it shut off for you guys?

according to my temp gauge at the lower water sensor on the driver side 135-140
When my mech fuel pump was going out it would revv to the moon just before high idle shut off

112
Some guys just put it on a switch.

Mine is 112 as well

Kdo58 said:

112
Some guys just put it on a switch.

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I love that idea, but my wife drives the truck too and I know she would never remember to switch it off

EDIT: actually a better idea would be to put the switch in series with the factory switch. That way it’s fail safe in the sense that the factory switch will eventually kill the circuit in case my wife forgets to turn it off.

Here’s my rudimentary design for a ‘wife proof’ high idle/cold advance manual shut off.

A momentary push button engages a latching relay… latching relay kills high idle and cold advance circuit… latching relay is reset when engine comes to temp and switch opens up and drops out an interposing relay that resets the latching relay.

I’ll see if I can make this happen through scrap parts from work. Not often do I do anything with 12V, mostly 125VDC and 48VDC systems. Looks complicated but it’s really two relays and a push button.

112 on my 86, I have it set to 1000 RPM high, 700 RPM low

Like 20 on my service truck lol. Something wrong there… was warm enough when I bought the truck that I thought it didn’t work at all, found out the next morning I was wrong…

When I bought the truck 10.5 years ago, I wondered why the Engine started racing when cold. Figured out this little gizmo was the problem. Unplugged the wire and solved the problem.
I don`t like a cold engine suddenly reving up to a high RPM.
I plugged it in a few weeks ago to check it, and still works.

I would rather use a Choke Cable to pick up the RPM`s when I want.

OH NO! What`s a Choke Cable? I forget there are youngsters on the forum and side lines.
It controls the Choke on a Carburetor on engines from the old days, when the engine was cold. Kind of like the 4 play knob, gotta play with it to get the old girl warmed up so she would cooperate.



Goat

Old goat I prefer my auto choke, cause I'm lazy. My old 1980 f250 had an electric choke, and before I engine swapped my samurai it had a coolant controlled choke. Who needs more pull cables going to their cab? By the way I'm only 32
Oh and my fast idle is still hooked up on my idi, and will remain connected. It does have an adjustment to turn it down.

I put my high idle on a toggle switch, only use it hor jump starting something. I also dialed the rpm back alot from where it was set when I got it.

James

My temperature switch went bad on this circuit. So I have no high idle at all either. Never really miss it. Once you get one of these engines running, it's not like a gas engine, I have never had it stall on me because the engine is cold.

Old Goat said:

I would rather use a Choke Cable to pick up the RPM`s when I want.

OH NO! What`s a Choke Cable? I forget there are youngsters on the forum and side lines.
It controls the Choke on a Carburetor on engines from the old days, when the engine was cold.

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I still have one of those on my Red Truck. I love that carb and don't want any other kind on there.

Nero said:

It does have an adjustment to turn it down.

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Plus it's adjustable with the mounting bolts too. It's just not a fine adjustment.

I absolutely LOVE manual chokes. Had them on my 60’s Fords, what a treat. The 63 had a 292 Y block with a Holley 4 barrel, never could get that damn thing to run right. Had better luck with the 65, had a 330 FE and a 2 barrel Holley. I got it to run good without much trouble. But I think the carb was junk on the 63. The 65 had a relatively new carb when I got it.

Sold the 65 for good money, about a month after I bought the 63. The 63 had pretty sweet paint, but I got fed up with trying to get it to run properly, and the top end had some wear damage from lack of oil, since those Y blocks don’t put enough oil to the heads, so I sold it cheap, listed with known problems, and picked up my 86 2 days later. Had the 65 just under a year, the 63 about 4 months, and have had the 86 just over a year, and counting. And my 91 service truck only a few weeks, and definitely keeping it around too…

The high idle temp sensor is bypassed in my truck, so I put the high idle on a toggle. Great for longer idling or battery charging here when it’s -50. Starts WAY easier than without.

lsaami said:

The high idle temp sensor is bypassed in my truck, so I put the high idle on a toggle. Great for longer idling or battery charging here when it’s -50. Starts WAY easier than without.

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You do press on the accelerator pedal when starting? That is proper procedure and should make it start easier than relying on the high idle solenoid. Here's the factory procedure on back of the sunvisor.

PC280010 by D Franklin, on Flickr