Cigarette Lighter Fuse

[Bill B.]

65, 327 Coupe

I just got my instrument panel installed tonight and I'm thinking maybe I made a mistake and I'm hoping the electrical experts will help me. I installed a fuse holder with a 15 amp fuse into the red 14 ga. wire for the lighter. I crimped and soldered the wires and put heat shrink on. I checked out the lighter and it worked great. When I was tucking the wire up under the dash it dawned on me that the fuse holder wire is smaller than the 14 ga. red factory wire. I'm guessing it's 18 ga. I'm kicking myself for not noticing the wire differences until I was finished. I'm not an elec. expert but I think I need to redo the job with heavier wire for the fuse holder. Can anybody give me some advice. Thanks in advance.

Bill B.

[Richard G.]

Re: Cigarette Lighter Fuse

According to the standard DC charts 14G wire is good for 15A up to a six foot wire.
According to the standard DC charts 16G wire is good for 10A up to a six foot wire.
If it is indeed 18G the load is close to 5A depending on the length.

Automotive wiring is typically as small a gauge as possible and still function and not overheat.
The wire size can also be time weighted. Loading for a short time would make a smaller size possible than a continuous load.
Max amp for a continuous time period is a good way to heat the wiring.
To be on the safe side you should redo the wiring as GM left very little wiggle room.

If you are the practical type? Run the lighter a couple times with your hand on the wiring and see if it gets warm.
Complete this test with the motor off, this will give you the worst case scenario with only 12V. (highest amp draw)
The load type (resistance) will tolerate a voltage drop quit well and the small wire is very short in length which helps.

I don't know the actual amp draw of the lighter except its less than 15A or the exact wire size. Both variables make the question more difficult to anwser.

Rick

[Gary C.]

Re: Cigarette Lighter Fuse

Bill,

Had a 1961 409 right after delivery, the lighter connector fell off and burned up the dash wiring.

IIRC cigarette lighter wiring is 14 ga, which equates to a 15 amps. Thus you would need a 15 amp fuse and 14 gauge wiring to the fuse holder.

18 gauge fuse holder wiring runs the risk of being overdrawn and melting the insulation. Thus becoming a potential fire hazard IMHO.

Gary
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[E B.]

Re: Cigarette Lighter Fuse

Is there point deduction for presents of in-line fuse or is it considered a safety issue? Ed

[Harry S.]

Re: Cigarette Lighter Fuse

Fuse panel and wireing is 5 points for originality and 5 points for condition. If you assign 2 points to the fuse panel and 3 to the wireing you will take a 20% hit on 3 points. (configuration from CDCIF). this is .6 of a point. Maybe or maybe not on a 1 point hit.

[Gary C.]

Re: Cigarette Lighter Fuse

Both Wagner & Casco made fuses that went on the back of the cigarette lighters.

https://www.ebay.com/itm/NOS-Cigarette-Lighter-Circuit-Breaker-Fuse-12V-Casco-Lighters-GM-Ford-Mopar-AMC/222792427182?hash=item33df76a6ae:g:bQ4AAOSwHGxb4bSd:rk:2:pf:0

[Bill B.]

Re: Cigarette Lighter Fuse

Both Wagner & Casco made fuses that went on the back of the cigarette lighters.
https://www.ebay.com/itm/NOS-Cigaret...4bSd:rk:2:pf:0

Is that fuse a one time use and needs replacing if there is a short? I just pulled the fuse holder that I installed last night and was on my way to get a correct one when the wife told me I needed to get back on the bathroom remodel were doing so it'll be a day or 2 before I can get the fuse installed. I've decided to go with a blade type 15 amp fuse

[Patrick B.]

Re: Cigarette Lighter Fuse

Both Wagner & Casco made fuses that went on the back of the cigarette lighters.
https://www.ebay.com/itm/NOS-Cigaret...4bSd:rk:2:pf:0

[Gary C.]

Re: Cigarette Lighter Fuse

Patrick,

Lighter housing should be the same across several models. You can check the Chevrolet Parts Books and see what all Chevy models the lighter housing was used on.

As an example; part number 7008642 fits 55-60 Corvette, 55-7 Passenger Car and 55-9 truck.

Gary
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