Hood Lock Install, '69 C20

[PapaNui]

After 68IRON, had his truck stolen only a mile or so from my house (since recovered) about a week ago, I realized that could have been me. My truck('69 C20) is probably just like most everyones, worn ignition, door locks, that any old key works, and no locking hood.

The locks were easy enough to take care of, just ordered a set of new keyed alike locks from GMCPauls, for less than 40 bucks, including the glovebox. Installation was no problem.

Now the hood presents different problems, there is no easy retrofit from another model GM. I didn't want to use a hunk of chain, and a padlock, so I did a little searching and the only real viable option I found was the Megatronix HL-6. The kit is not only a hoodlock, but also has a one wire ignition interrupt. A couple of threads, have been posted here in the past on the Megatronix, and after installing one on my own truck, I'm surprised more people are not using one.




The Megatronix HL-6 kit comes with all the parts you need. I bought this kit off Amazon.com for a little over $80. Quality is actually quite good.




Begin by installing the lock portion under the dash. I chose the left side of the steering column, and ran the cable over the fusebox, through a factory made hole with a rubber plug that the Tach wire runs through. I just cut a 1/2", hole in the plug, and ran the cable through, and attached a set collar with the lock screw.



Next is the Hood Latch, this is the hardest part of the install. I aligned the end of the latch, where the pin comes out, inline with the hood pin on the truck. The kit gives you a weird glob of clay, with some goofy instructions on what to do with it.
I just mounted the latch, and marked the end of it by reaching up behind the grill. The portion of the latch that attaches to the hood, needs to be bent to length. Again crawl under the bumper, and measure the gap between the hood and radiator support where latch is attached. I bent mine in a vise, the used a small magnet to hold it to the latch, so I could mark the exact location on the hood for mounting.



Latch mounted to hood.



Attach the cable to the latch, and fine tune. The pin screws in and out, and locks with a nut. The instructions say leave a 1/16" sticking out in the open position. The kit comes with a couple cable hold down clamps, I put one on the inner fender, and the other on the radiator support.
When locked, my hood only opens about a 1/4" when the factory hood latch is pulled. Not enough room to get pry bar in, or even a finger.

Next install the ignition interrupt. The wire comes out of the cable, and simply connects to the Tach, side of the Distributor, with the included inline fuse, and ballast. Please look at second picture for reference( I can't attach anymore pics). I installed mine so it could be removed if I just wanted to use the hood lock only.
When locked, a thief could crank the engine till the battery dies, but it aint gonna start.

Overall, for the money, and clean installation, the Megatronix HL-6, is well worth it.

[tommys72]

looks like a good buy to me.

[swamp rat]

Thank you!

[dmjlambert]

Could you please describe how it works? Under what circumstances do you use the key, when you start the truck? Or when you open the hood? Do you turn the key? What do you do to make the pin unlatch the hood? The amazon web page says it is for older cars without electronic ignition, does that mean it will not work with or will damage an HEI? Sorry about all the questions, I just can't imagine the basic ideas of how this works.

[PapaNui]

Originally Posted by dmjlambert

Could you please describe how it works? Under what circumstances do you use the key, when you start the truck? Or when you open the hood? Do you turn the key? What do you do to make the pin unlatch the hood? The amazon web page says it is for older cars without electronic ignition, does that mean it will not work with or will damage an HEI? Sorry about all the questions, I just can't imagine the basic ideas of how this works.

No problem, to engage the hood lock, you simply push the lock portion in. This pushes the cable forward into the latch attached to the hood. The hood is now locked, the ignition is also disabled, not allowing the truck to fire. It will crank, but will not start.





The lock is spring loaded, so when you unlock it with the key, it pops out, unlocking the hood, by pulling the cable back. At the same time the ignition kill is turned off, allowing the truck to be started as normal.



When the lock is engaged(locked) the hood will not open, and the truck won't start.
When unlocked, the truck will start, and the hood will always be unlocked.

My truck has a HEI distributor, and it works just fine. The kill wire simply attaches to the tach drive of the distributor.

The Megatronix HL-6, seems like its complicated, but far from it. Basically, it is a cable, with a tubular lock, and a kill switch.
The hardest part of using it is remembering to unlock the lock, before starting the truck.

[Oregon 1967 GMC]

Thank you for sharing. Mine's still apart but will have this worthy investment once done. I go to Mariner and Seahawk games (when the Rams are in town) I might beg for your help, were you able to do it in a day?

[GR8-68]

Cool feature to add for a little bit more security

[ls1nova71]

This sounds like a good idea, as long as you use it. I understand the idea behind having to have it unlocked to start, (fire under hood, you want to be able to open it without fumbling for keys) but it seems like to me it would get old having to unlock the hood every time you want to start the truck, but I guess if you had to leave it in a sketchy neighborhood it would keep someone from walking off with your Optima battery. The sad part is these trucks still have the super easy to hotwire ignitions and no column lock to deal with.

[Crappie Hog]

PapNui I see that they also have the Megatronix HL-7 which would be 7ft. So did the HL-6 fit just right length wise or would the 7ft one be better?

[PapaNui]

Originally Posted by Oregon 1967 GMC

Thank you for sharing. Mine's still apart but will have this worthy investment once done. I go to Mariner and Seahawk games (when the Rams are in town) I might beg for your help, were you able to do it in a day?

This can be installed easily in a day. When you are ready to install the kit, hit me up and I can measure out some mounting dimensions for you. That should help make the installation easier. GO HAWKS!!

[PapaNui]

Originally Posted by ls1nova71

This sounds like a good idea, as long as you use it. I understand the idea behind having to have it unlocked to start, (fire under hood, you want to be able to open it without fumbling for keys) but it seems like to me it would get old having to unlock the hood every time you want to start the truck, but I guess if you had to leave it in a sketchy neighborhood it would keep someone from walking off with your Optima battery. The sad part is these trucks still have the super easy to hotwire ignitions and no column lock to deal with.

Like the man said, "Give Me Convenience or Give Me Death". Nothing works if you don't use it, so can't help you there.

I made this thread to show a cleaner alternative to the old chain and padlock. When the lock is engaged, the ignition is killed. It cannot be hot-wired.

I believe the Megatronix kit, for the money, and simplicity, is one best deals out there. Sure you could go to Car-Toys, or some other stereo shop, and pay hundreds more for some noise making gizmo, but will it lock the hood?
This is a lot easier than having the "Club" steering wheel lock, bouncing around your cab when not using it. Even worse, have you tried using pedal locks?
I have no affiliation with this company. I just like things that are simple, economical, and work.

[PapaNui]

Originally Posted by Crappie Hog

PapNui I see that they also have the Megatronix HL-7 which would be 7ft. So did the HL-6 fit just right length wise or would the 7ft one be better?

I was kind of wishing I should have ordered the HL-7, so the cable could be routed closer toward the drivers side fender for a cleaner install. Although I'm happy with the way the HL-6, came out.

[Oregon 1967 GMC]

Originally Posted by PapaNui

This can be installed easily in a day. When you are ready to install the kit, hit me up and I can measure out some mounting dimensions for you. That should help make the installation easier. GO HAWKS!!

It'll be a few months and I might take you up on that in a few months. Maybe I'll get the HL-7 and mount it through the fender. You have a nice looking truck. Thanks again for the idea.

[72Cheyenne454]

Thank you for taking the time to share.

Just curious, how does a wire feeding into the tach side of the distributor disable the ignition?

On my HEI, I'm using the tach lead to power my factory tach, so can I just splice this unit into the tach wire?

Thanks!

[PapaNui]

Originally Posted by 72Cheyenne454

Thank you for taking the time to share.

Just curious, how does a wire feeding into the tach side of the distributor disable the ignition?

On my HEI, I'm using the tach lead to power my factory tach, so can I just splice this unit into the tach wire?

Thanks!

I like to know that myself. I'm guessing it either grounds out,or interrupts the ignition circuit somehow. Maybe someone here with more electrical expertise could enlighten us on its inner workings. I do know if the engine is running and you push the lock in, it will kill the engine.

I also have a factory tach dash, and it works fine. When I installed mine, I made it so the lead from the Megatronix cable, could be disconnected from my tach wire.

[junksaver]

If you ground the tach side of a HEI distributor it disables the ignition. You can make up a cheap antitheft device just by running a wire from the tach side of the distributor to a ground with an on/off switch.

[PapaNui]

Originally Posted by junksaver

If you ground the tach side of a HEI distributor it disables the ignition. You can make up a cheap antitheft device just by running a wire from the tach side of the distributor to a ground with an on/off switch.

Thanks for the info.

[mooseboy84]

Cool idea but the simplicity of a piece of chain and a lock is nice. Take a string, run it up in the little holes in the hood part, then let it hang under the where the lock closes. Its about 2 feet you need, maybe less, and a little lock.

A whole lot cheaper and easier, and will prevent windows shoppers. If someone wants under the hood enough, theyll get in.

I do like the ignition interrupt part of it.

[swamp rat]

Originally Posted by mooseboy84

Cool idea but the simplicity of a piece of chain and a lock is nice. Take a string, run it up in the little holes in the hood part, then let it hang under the where the lock closes. Its about 2 feet you need, maybe less, and a little lock.

A whole lot cheaper and easier, and will prevent windows shoppers. If someone wants under the hood enough, theyll get in.

I do like the ignition interrupt part of it.

Pad lock or like a spring loaded latch?

I used to do the chain trick after my rebuild 20 some odd years ago, then i promptly lost the lock so i got a nut, bolt and washers because i figured that dealing with that would still be enough noise to thwart a thief and or wake me and my dog up in the middle of the night, one day i unthreaded the bolt and instead of removing it i just screwed the nut and washer back on, it worked and kept the bolt in the same link of chain so i got in the habit of doing that, but one day the bolt turned and caught the radiator when i opened the hood, yep got a nice hole in the core that i had to have closed off, end of the bolt, nut and washer trick..

[Kenfuzed]

Anyone know if this hood lock will work on a 66 C10?

[cblock]

That looks like a great gizmo to have on your truck, I at the moment have my truck not running (in the process of an engine swap). I find the kill switch part interesting, but if you ground the tach connector on an hei distributor can you cause any damage?

[PapaNui]

Originally Posted by cblock

That looks like a great gizmo to have on your truck, I at the moment have my truck not running (in the process of an engine swap). I find the kill switch part interesting, but if you ground the tach connector on an hei distributor can you cause any damage?

From what I understand the answer is yes. Some say the coil, and some say the module, could be damaged if you are using a direct to ground, as with a kill switch.

The Megatronix kit, has an inline fuse, and load resistor, that wires between the tach lead, and ignition immobilizer. You switch off the ignition immobilizer, before you energize the ignition, by turning the key in the ignition, so it shouldn't have an affect on the distributor.

Now when a thief gets in your truck, I guess they could crank the engine until they fry the module. Either way, they're not going anywhere, and a new module is cheaper than losing a truck.

[slikside]

Sub'd

I think it's pretty cool...Convenient, double protection.

Agree that a 7 footer would probably enable a cleaner install.

Thanks for sharing.

[tommys72]

So are you able to use a tach still being that this plugs in where the tach goes?

[PapaNui]

Originally Posted by tommys72

So are you able to use a tach still being that this plugs in where the tach goes?

Yes, it taps into the tach wire, not replace it. Your tach will operate as normal.