Ok, I have a Crossfire Z28 hood on my 91 RS, and I had it hooked up to be open when ever the car was on. This, of course, DESTROYED the stock solenoid.

Im looking for something that will run on 12 volts and can handle running consistently for hours...

 

You have several options.
A same size solenoid with the same pull strength would have to be water cooled in order to survive. Exotic, expensive, and might not exist.
A much bigger solenoid could give the same pull and survive, but might not fit.
An advanced solenoid with a pull-in winding, a holding winding, and a built-in switch could be the same size and give the same pull w/o the need for cooling. Expensive, and might not exist.
An electronic circuit that applies full power initially but then reduces applied power. Still it might not be enough.
The underhood temperatures and the temperature tolerance of windings does not give much safety margin.
I'm sorry for only being theoretical here, but you might have to rethink your strategy around your wish to keep it open continously. Other ways to solve it might be more viable.

 

Ok, so now Im back to trying to figure out how to only have it open at WOT.

I have thought about somehow hooking it into a shift light, so it only comes on at 3500 or better.

What about somehow setting up a way for it open with vacuum, but I cant think of any way to make this work without spending WAY too much money.

 

I'm not familiar enough with the under-hood details of those cars to make a specific recommendation, but how about fabbing a small bracket for a micro-switch being activated by the throttle? They should be available at Radio-Shack, Digi-Key, Mouser, etc. for around $2-3. (Or for free out of an old copy-machine.) They come in several sizes and varieties. You can read about them here: http://en.wikipedia.org/wiki/Micro_switch
Vacuum switches are nice but harder to come by.

 

I remember this being discussed here a few months ago. Try searching, you might be lucky and find it.

One solution would be to have two solenoids with travel limiters and NO spring on the flap. One solenoid would open the flap when you turn the ignition on and turn itself off (with the travel limit switch). Then once you turn the ignition off, the other solenoid would close the flap and turn itself off.

Or you could attach a mechanical cable, that'd be the most reliable and cheapest way to do it.

Lou

 

So your thinking run a cord from the throttle to the back of the hood and then up to the linkage? Seems like it could work, the only problem I see is that when I open the hood it would pull against the cord, opening the throttle and the hood flaps....

 

You could not run a simple cord, of course. It would have to be a cable in an enclosure so that you can open the hood without pulling on the cable.

What I meant originally, though, was to have a manually actuated cable in the interior so that you can open/close the flaps at any time you wish (due to rain etc).

But linking it to the throttle cable is not a bad idea. It would have to be done right, though.

Lou

 

Lou, you have a real good idea with the 2 solenoid thing.

 

Im also leaning towards this idea. Where would I get these solenoids? Sound like door lock type solenoids almost.

 

Actually, they do exist for industrial applications. The first one that came to mind was the fuel shut-off solenoind for a Bobcat skid steer. That would be kind of big, though. The second one that came to mind would be one from a Kubota generator with an auto idler. That solenoid is small, rated for continuous duty and is 12 volt. Probably not real cheap but, I doubt it would break the bank. Maybe another brand like Homelite or Coleman would be cheaper. I don't have any part numbers so you'd have to Google it.

Hope this helps in some way.

 

Im retarded and cant find it....

 

I found this: http://www.apelectricshop.com/p-754-...-solenoid.aspx
From the looks of it, it wouldn't pull too far without adding a bellcrank or a pulley setup to operate your hood. But there must be others on that site.

Heck, you could probably modify a transmission kick-down cable to open your scoop. The door lock solenoid idea sounds do-able too.

 

Zwrench, Im a little confused. The solenoid you linked me to, I dont see the moving part.... I feel retarded...

 

No need to feel that way. The plunger and spring are sold seperately on the same site.
Like I said, though, that solenoid looks too small for what you need anyway. I only linked to it so you could explore that site for yourself to see if there was anything you could use. You've also gotten some good suggestions from others in this thread. It just depends on your creativity as to what you want to use.
Good luck and have fun!

 

You are right, the doorlock solenoid idea sounds very good, I didn't think of that. That would be probably the easiest way to do this.

And I've done things with an auto kick-down cable before. Like fabricate my missing tonneau cover release mechanism. Spare parts can be pretty useful.

Lou

 

The original hood louver operation was controlled by the ECM. When WOT was sensed, the ECM would output a signal which operated a relay. When the relay operated it closed a contact that provided power to the solenoid. When you eased up on the pedal, the ECM would detect some percentage change from the WOT position and deenergize the relay. The solenoid would then be deenergized and the flaps would close. The relay that the ECM controlled was a second Fuel Pump relay.

If you want a solenoid that is rated for continuous operation, there are industrial varieties out there. I did find a few rated for continuous duty at 12 VDC. You also will need to know the push force and the length of the push rod must move. Anything with a push length over 1.0 inches is likely a custom order, and for one off not cheap . Also, as the push length increases the push force decreases. I do not know what these values are for the original solenoid.

Another option would be a latching solenoid. But then you would need two electrical signals, one to operate and latch the solenoid and another to unlatch the solenoid. You will need a dpdt toggle switch or a mulit-contact relay to implement the signals.

I doubt a door lock solenoid would work for this application. It is unlikely that they are rated for continuous duty. So toasted solenoid, Part II

I did have some conversations with another member here last spring. He ended up putting a microswitch on his carb that operated the solenoid, essentially when the carb was at WOT. He seemed happy with the results.


By the way, the part number for the original solenoid is 14043262. It is still available at www.gmpartsdirect.com for $46.xx plus shipping, tax, etc. You need to look in the alternate catalog section, under "Classic Cars" in the first year drop down box. AC Delco may also have the solenoid, but their part description is not very good. I am not sure if it is the solenoid or not.

Dave

 

Thank you Dave. Im thinking a door lock solenoid with a rocker switch that would flip them open, then the switch would return to its "Neutral" position, leaving no power going to the flaps, but allowing them to stay open. I would then rock it back to close them. Seems simplest to me....

 

The switch you'd need for that would be called "momentary On-Off-On" switch. You can check Fry's or other similar places.

Lou

 

Well, I found a 20 Amp switch at radio shak, and it will work great. The only problem is, this actuator only has two wires going to it, and they are suposed to reverse polarity to open and close the actuator. Because of this, I am going to have to get creative with the relays, but it should work. Also, the stock solenoid opened 7/8ths of an inch, barely opening the flaps, this one is just shy of an inch and a half.

 

SteeL

I guess I wasn't thinking about doing it that way. I just assumed the door lock solenoid would be on all the time. BigBabyLou has the switch part right, but you are still missing a piece. To retract the door lock solenoid and close the flaps you will need to reverse the polarity of the voltage to the door lock solenoid. This is a DC device, to have it reverse direction the current needs to flow in the opposite direction than when it is opened. Seems like the Door Lock Relay Assembly will do the trick.

An additional item to consider is how to power this circuit. What we have been referring to as the Door Lock Solenoid is listed as a Permanent Magnet Motor in my Shop Manual Schematics. It will require a bit more current than the hood flap solenoid. Search this board for a Power Door Lock wiring diagrams. I think I may have posted one several months ago. If you find one that I posted, it will be for the 1982 model year. I think in later years, the Fisher Body Junction block (C238) was eliminated. For your wiring, just eliminate one motor and one Open Close switch and you should have a good wiring diagram.

I am curious and wonder if you could post the diameter, length, and travel distance of the rod for the solenoid you "cooked". Just trying to see if the industrial solenoids I have found in catalogs match up at all. Ones rated for continuous duty seem to be listed for $25 - $35 or so. It is also unclear if the ones I have found have enough "push" force to open the flaps.

Dave

 

Dave, I supose my MS paint diagram wasnt clear. I have a ON-Off-ON switch, when forward it will send power to wire A, and relay B, allowing wire B to act as a ground wire. When back, it will send power through wire B, activating relay A, allowing wire A to act as a ground wire.

I will get measurements of the cooked one tomorrow.

Edit: Momentary On-off-on

 

Steel

I took a quick look at the diagram and wasn't quite sure how you intended it to work. Yes the contact rating for the relays you have are fine.

Take a look at this link. Among other things it has the connection diagram for the power door locks. I think if you wire up your switch and relays the same as the diagram, things will work fine. IF you are going to connect directly to the battery, an in line fuse or two might be a good idea. You can find them in the electrical section of any auto parts store.

I hope you don't plan on mounting your relays in the engine compartment if they are RS relays. They are not designed for that and after a year or two, the heat may crack the case. I am sure you will figure something out.

http://www.p71interceptor.com/thirdgen/powerlocks/

Dave