TheSamba.com :: View topic - Ambient temperature heat is melting my fuses

Sun Jul 28, 2024 4:21 pm

I did try searching, but not finding my exact issue. It's been a heat wave here around 105 to 115 F here. When the bug sits in the parking lot for example I'll come back to the car and the fuses will just be melted on the floor. Today I hopped on the freeway and the fuse connected to the ignition switch melted and fell out which instantly shut me down on the freeway, no good. I carry spare fuses which I put back in and carried on because by then then the ambient temperature inside the car cooled down, but I don't trust those things. I want to get some good quality ones, where do I get the best ones from?

Sun Jul 28, 2024 5:00 pm

If you want to keep the original type of fuses, these would likely be your best bet:

https://belmetric.com/thermoplastic-electrical-fuses/?

I don't think anyone is making ceramic ones anymore.

If you're interested in switching to ATO blade style fuses, you can get a well made fuse block at:

https://www.torquerestoparts.com

And use quality Bussman fuses. ATO fuses don't come as 8A and 16A, but they do come as 7.5A and 15A which will work fine.

Sun Jul 28, 2024 5:05 pm

Thanks, I’ll check into these links.

Sun Jul 28, 2024 5:11 pm

Since I am still 6 volts, do you think these blade fuse boxes would help get a better connection for brighter lights etc? Like the threads that mention soldering the original fuse box to get a better connection?

Sun Jul 28, 2024 6:59 pm

I put a Torque Resto in my 66 https://robonza.com/beetle/index.php/2024/04/29/installing-modern-blade-fuses-torque-resto-parts/ . It was an easy install, and in the heat of Moab has not melted. It has to be a better connection than the original one.

-Joe

Sun Jul 28, 2024 9:23 pm

KingAir42 wrote: Since I am still 6 volts, do you think these blade fuse boxes would help get a better connection for brighter lights etc? Like the threads that mention soldering the original fuse box to get a better connection?

I think the blade fuses have a greater contact surface area, so that is helpful with a 6v system. If you want to get more lumen bang for the buck, switch to LEDs ... they draw less current so impose less of a load on the system while delivering brighter light ... and good quality ATO fuses are a lot easier to find than the old style fuses.

Sun Jul 28, 2024 11:14 pm

Awesome, thanks for your help

Mon Jul 29, 2024 7:31 am

KingAir42 wrote: Today I hopped on the freeway and the fuse connected to the ignition switch melted and fell out which instantly shut me down on the freeway, no good.
You didn't ID the model year of your 6v Beetle so I can't say for certain... all of the VW wiring diagrams I have looked at place the ignition coil #15 wire on the INPUT side of the fuse. This means even if you remove the fuse the ignition coil will remain powered. Is it possible you have the coil wire connected to the WRONG side of the fuse? If you just move the wire to the OUTPUT side of the fuse so it is protected by the fuse... you have also added the load of the coil and everything else powered by the #15 coil wire to that fuse. You will likely overload the 8A fuse.

Check that your black #15 ignition coil wire is connected to the same terminal as the black #15 wire coming from the ignition switch.

I'm not saying 115deg temps won't melt plastic bodied fuses. But the ignition coil should not be impacted even if your remove every fuse from the fuse box. Unless the PO has done some "creative" wiring. :shock:

Mon Jul 29, 2024 7:47 am

Anyone still sell the ceramic bodies fuses?
Those must be some cheap-ass Chinese fuses if they are melting in the car!
And I agree, check the wiring; the ignition circuit is originally unfused.

Mon Jul 29, 2024 8:03 am

KingAir42 wrote: It's been a heat wave here around 105 to 115 F here.
So Bakersfield is hot but not as hot as Phoenix.

Well, I've lived in Phoenix since 1967, and have NEVER had any fuses melt due to heat. That would be for ANY vehicle we've had over that timeframe, and parked in my hot garage or out in the sun the vehicles get to like 140F.

I suspect low-quality fuses.

Mon Jul 29, 2024 9:10 am

Blade fuses? Not for me, keep it original, the old bullet type worked for decades just fine. Sorry but I consider blade fuses as a hack if it is to solve a fuse problem, save those for a heavily modified Bug, Baja or kit car. conversion of a otherwise stock Bug to blade Fuses is sacrilege, God frowns on that!!!! :lol:

The melted fuses are no doubt the lowest quality around, and reeks of cheapo chinesium quality. Try another brand.

Did you know you can reuse blown ceramic fuses by removing the good fuse metal from a plastic fuse and installing it on the ceramic fuse body??? I never throw away my blown ceramic fuses, I rebuild them!!!! Easy Peasy!!!!!

Besure to clean up the ends of fuses till shiny for best contact, do likewise to the spring clips and retension the clips to assure a tight fuse connection, then they will perform like new!!!!!

Save those blown ceramic fuses!!!!!!! Rebuild them forever!!!!!

PS here is a seller (one of many) on ebay of ceramic fuses for example. I got no affiliation with this seller...

https://www.ebay.com/itm/405078599014?chn=ps&_...34ce50f9c6

Do a search on the web for "ceramic bullet fuses" and you will find many sources. That is how I found this ebay ad in under 30 seconds.

Good luck, stay cool, dont melt!!!!

Bakersfield, how ironic, them fuses baked alright!!!

Mon Jul 29, 2024 9:30 am

ashman40 wrote: KingAir42 wrote: Today I hopped on the freeway and the fuse connected to the ignition switch melted and fell out which instantly shut me down on the freeway, no good.
You didn't ID the model year of your 6v Beetle so I can't say for certain... all of the VW wiring diagrams I have looked at place the ignition coil #15 wire on the INPUT side of the fuse. This means even if you remove the fuse the ignition coil will remain powered. Is it possible you have the coil wire connected to the WRONG side of the fuse? If you just move the wire to the OUTPUT side of the fuse so it is protected by the fuse... you have also added the load of the coil and everything else powered by the #15 coil wire to that fuse. You will likely overload the 8A fuse.

Check that your black #15 ignition coil wire is connected to the same terminal as the black #15 wire coming from the ignition switch.

I'm not saying 115deg temps won't melt plastic bodied fuses. But the ignition coil should not be impacted even if your remove every fuse from the fuse box. Unless the PO has done some "creative" wiring. :shock:

Sorry, it’s a 62 bug. I’m checking the wires that you mentioned above

Mon Jul 29, 2024 9:42 am

I've purchased Volkswagen 20pc Ceramic/Bakelite 8amp White Fuse NOS from Florida Metrics on eBay-good quality and reasonable priced.

Mon Jul 29, 2024 9:47 am

This fuse melted, which shut me down on the freeway.

Black closest to picture is the coil wire. The one behind it goes to the ignition switch.

Mon Jul 29, 2024 9:50 am

One or both end fuse positions are wired wrong.
Consult this diagram (top is front of car; your photos are opposite):

Mon Jul 29, 2024 9:51 am

Just in case you don't have the wiring diagram handy ...

https://www.thesamba.com/vw/archives/info/wiring/bug_62.jpg

https://www.thesamba.com/vw/archives/info/wiring/bug_62_key.jpg

"D" is the ignition switch. I believe the black wire connecting 15/54 to the unfused side of 8 is the one ashman40 is speaking of.

Beat me to it Phil! :)

Mon Jul 29, 2024 9:55 am

Thank you, definitely have the diagram and all the manuals. So when they say the input side and the output side of the fuse box, if I draw an imaginary line down the middle of the fuse box with the half that’s closest to the headlights or front of the car be the input or output side? And then the other half of the fuse box that’s closest towards the rear of the car be the other option? I just can’t tell which is input and output from the wiring diagram.

I switched these red wires around. Looking at the diagram it just looked like I needed to switch these two positions and I’m probably wrong but that’s just what it looked like to me. And also looking at the diagram it still looks like the black wires, the coil and the ignition wire still in the right spot, but I’m not quite understanding the input versus output

Mon Jul 29, 2024 10:06 am

The fact that just one fuse is burning suggests that you do have a problem on that far-right position where the HOT 30 is from the light switch, and looking at it, you do have it wired incorrectly.

Since you have a '62, I would use these diagrams below, these should be more like your setup.

Mon Jul 29, 2024 10:07 am

KingAir42 wrote: So when they say the input side and the output side of the fuse box...
The "input" side of the fuse block is closest to the dash.

I see you switched it, it all looks normal to me now.

Mon Jul 29, 2024 10:08 am

Rear is input (unfused ) side.

Fuse #1 in the top picture is supposed to have the radio and dome light attached to it on the fused side ... nothing that would cause the engine to shut down if the fuse blew. Your second photo seems to show the wire from the ignition and wire to the coil attached to the unfused side of #8 as it should be.