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72 Roadrunner hood springs

Posted By: 471Magnum

72 Roadrunner hood springs - 10/31/10 10:32 PM

I'm convinced my Roadrunner is trying to kill me. It has made several attempts to decapitate me.

Apparently, it does not have the correct hood springs on it. They barely have enough strength to hold the hood open. The slightest disturbance will send the hood crashing down. I've been using an old broom handle as a safety measure. While it's an effective temporary solution, it's a bit tacky.

I've since learned that Roadrunners use a heavier spring than the Satellites. This is regardless of Air Grabber or not, and all Roadrunners use the same spring.

Unfortunately, there is a shortage of 71/72 Roadrunner parts cars around here from which to harvest a set of springs.

I have come across several 71-74 Chargers though, and they seem to have a heavier spring. I nabbed a pair in a recent trip to the salvage yard.

Does anyone know for sure if these are the same as Roadrunner springs? They're definitely heavier than the one currently on my car. They aren't too strong, are they? I don't want to have the opposite problem and the rear of the hood bulge up. I'd like to know for sure before I go to the trouble of blasting, painting and installing these.

Also, any tricks to installing them without causing grievous harm to surrounding painted surfaces?
Posted By: AZ-Nick

Re: 72 Roadrunner hood springs - 10/31/10 11:30 PM

I was trying to write this all out but there was too much in differences to write so I decided to put this in the post instead..... You may want to click on the attachment for a larger size. As you can see there were a few different coils for 71 and I am sure they extended to 72.

Attached picture 6278166-HoodHingechart.jpg
Posted By: 471Magnum

Re: 72 Roadrunner hood springs - 10/31/10 11:32 PM

Okay AZ-Nick.... you posted and deleted. What's up with that?

The ones currently on the car have about 18 coils. The ones I pulled off that Charger have about 20 coils.

Haven't seen anything that looks like the 25 coil spring you mentioned.
Posted By: AZ-Nick

Re: 72 Roadrunner hood springs - 10/31/10 11:46 PM

I did repost it while you were writing...
Posted By: 471Magnum

Re: 72 Roadrunner hood springs - 11/01/10 12:34 AM

Quote:

I did repost it while you were writing...


Do'oh! Curse you slow fingers!
Posted By: 471Magnum

Re: 72 Roadrunner hood springs - 11/01/10 12:43 AM

The way I'm reading that chart, RM air grabber springs (3586092) are the same as Charger springs w/o fresh air, which means I'm good to go. The Charger I sourced my from was not an N96 car.

As far as the coil counts, I guess I'd have to check out my buddy's 72 Rallye w/ N96 to see the 25 coil spring.
Posted By: MoparMarq

Re: 72 Roadrunner hood springs - 11/01/10 01:09 AM

Seems like 25 coils would be a weaker spring than
18 coils.

FWIW, the hood hinge springs (the originals) on my '72 RR w/o factory A/G are 18 coils.
Posted By: 471Magnum

Re: 72 Roadrunner hood springs - 11/01/10 01:27 AM

It's really the gauge of the wire more than the number of coils that determine the strength, especially when the springs are relaxed.

The 18 coil springs on the car now measure about .223". They definitely aren't getting the job done.

The 20 coil springs off the Charger measure .201".

Hmmm....
Posted By: superbyrd

Re: 72 Roadrunner hood springs - 11/01/10 01:28 AM

hinges on my 72 satellite were tweaked,and i installed a pair from a 73 charger rallye that had a bulge hood. don't remember the coil count,but they worked like normal. not too stiff,and didn't try to take me out.
Posted By: RestoRick

Re: 72 Roadrunner hood springs - 11/01/10 01:54 AM

Quote:

I'm convinced my Roadrunner is trying to kill me. It has made several attempts to decapitate me.

Apparently, it does not have the correct hood springs on it. They barely have enough strength to hold the hood open. The slightest disturbance will send the hood crashing down. I've been using an old broom handle as a safety measure. While it's an effective temporary solution, it's a bit tacky.

I've since learned that Roadrunners use a heavier spring than the Satellites. This is regardless of Air Grabber or not, and all Roadrunners use the same spring.

Unfortunately, there is a shortage of 71/72 Roadrunner parts cars around here from which to harvest a set of springs.

I have come across several 71-74 Chargers though, and they seem to have a heavier spring. I nabbed a pair in a recent trip to the salvage yard.

Does anyone know for sure if these are the same as Roadrunner springs? They're definitely heavier than the one currently on my car. They aren't too strong, are they? I don't want to have the opposite problem and the rear of the hood bulge up. I'd like to know for sure before I go to the trouble of blasting, painting and installing these.

Also, any tricks to installing them without causing grievous harm to surrounding painted surfaces?



Installing and removing the springs can be done on the car using a 1" wide belt ratchet strap.
Fashion a loop with the strap long enough to allow catching the front eye of the spring and reaching the other end of the loop at the front of the car. Hook the front eye of the spring and pull from the front of the car. A helper is a good idea to catch the spring as you release the tension after unhooking it from the hinge.


Rick
Posted By: 72roadrunnergtx

Re: 72 Roadrunner hood springs - 11/01/10 02:47 AM


Started with these original Satellite flat hood springs for my A/G retrofit, look at it wrong, the hood would fall. 18 coils, not sure of wire dia. but smaller that springs below.


Bought a set of Charger hinges off eBay that came with these springs, .245" wire, 18 and a half coils(note the way the last hook faces).


Made this tool to easily handle replacing springs. Some bailing wire, a short piece of 3/8" steel tubing, and a little duck tape to protect the freshly painted springs.
Posted By: dangina

Re: 72 Roadrunner hood springs - 11/01/10 03:24 AM

time to go with a fiberglass hood
Posted By: lahatte

Re: 72 Roadrunner hood springs - 02/07/11 04:46 AM

To 72roadrunnergtx,

I see a water valve in your engine compartment. Can you say where you got it?

Thanks.
Clay
Posted By: screamindriver

Re: 72 Roadrunner hood springs - 02/07/11 05:14 AM

Quote:

To 72roadrunnergtx,

I see a water valve in your engine compartment. Can you say where you got it?

Thanks.
Clay

They're on E-bay all the time and prices vary so don't rush into the buy...Also, classic auto air in Fla. is one of the vendors that carry them....
Posted By: lahatte

Re: 72 Roadrunner hood springs - 02/07/11 05:17 AM

Thanks. I've seen them at Classic Auto Air. Just wondering if there miight be a better deal.

Thanks.
Clay
Posted By: screamindriver

Re: 72 Roadrunner hood springs - 02/07/11 05:24 AM

I just did a quick search and Ebay is looking a little sparce right now....But keep looking the next few weeks and you'll see them...I've seen them go from 50-350 for basically the same bakelite piece...Get creative on the keyword search like "mopar water valve" or "road runner water valve" etc... And you'll run the chance of finding an obscure auction listing at a good deal...
Posted By: 72roadrunnergtx

Re: 72 Roadrunner hood springs - 02/07/11 06:53 AM

As mentioned, I picked up both of mine(need a spare or two if running this original style valve) off E-bay a couple of years back while collecting parts. Don't recall what exactly I paid for them but would have been around $100 bucks or less. You may be interested in a recent thread relating to these vales & brackets.
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