fusible link

[broncobuckinaround]

how many amps is the fusible link for the headlights. im talking about the one closest to starter solenoid. if looking at the diagram its fuselink D

 

[Big Jim M]

Fusible links are a way to install a fuse in a wiring harness where an actual fuse would be bothersome for weather or other reasons.
These links are always 4 gauge sizes smaller than the wire they protect. So one should observe the wire connected to the link before purchasing a new link. Here is a list from a local vendor:
18ga. Fusible Link protects 14ga. or heavier wired systems
16ga. Fusible Link protects 12ga. or heavier wired systems
14ga. Fusible Link protects 10ga. or heavier wired systems
12ga. Fusible Link protects 8ga. or heavier wired systems
Big Jim

 

[jeremysdad]

Big Jim, your truck is the one I wanted but couldn't afford bitd...lol

Back on topic, it is very important to replace a fusible link with a fusible link unless you like watching your vehicle burn to the ground.

That being said, is it 'improper' to replace a fusible link with an inline fuse of appropriate wire gauge and fuse rating for the circuit in question?

For example: I melt a fusible link, but happen to have an aftermarket in-line fuse holder in my elec parts box. Rather than hitch a ride to the parts store, I wire in the fuse holder, and install an appropriately rated fuse. Potential issues?

Addendum: User should attempt to diagnose/repair why original fusible link blew.

 

[RonD]

how many amps is the fusible link for the headlights. im talking about the one closest to starter solenoid. if looking at the diagram its fuselink D

In this diagram: http://www.therangerstation.com/tech_library/EDiagrams/files/Diagram_Headlights_1983to1989.JPG

It shows D = 16gauge


You can replace fusible link with inline fuse but....................one of the other reasons fusible links are used, and are still used on alternators, is that they can handle a temporary amp spike without "blowing", they heat up then cool down, like when a headlight or other light bulb goes out it's small wire can short but wire in bulb will burn out faster than Fusible link so link stays working and so do all the other lights on the vehicle.

 

[jeremysdad]

In this diagram: http://www.therangerstation.com/tech_library/EDiagrams/files/Diagram_Headlights_1983to1989.JPG

It shows D = 16gauge


You can replace fusible link with inline fuse but....................one of the other reasons fusible links are used, and are still used on alternators, is that they can handle a temporary amp spike without "blowing", they heat up then cool down, like when a headlight or other light bulb goes out it's small wire can short but wire in bulb will burn out faster than Fusible link so link stays working and so do all the other lights on the vehicle.

I was just wondering.

 

[broncobuckinaround]

thx to all.

a friend and i believe it was caused by the headlight switch.

but not exactly sure. my friend works for exotic racing co. in las vegas at the speedway. he one of my go to guys for pretty much everything. i come you guys for the things he can answers cuz hes not a b2 owner.

anyways. i fabed a 50amp fuse into the line because i had a 30 that just kept blowing. at times the alternator wouldnt charge and other times it would be. everytime it didnt charge it would blow the fuse when it kicked on. brand new alt btw. but when everything is working right the charge wire from the alt is the only one that gets warm. my alt puts out 14.56v.

not that i put the bigger fuse in everything is working. if it pops i know there is a bigger problem

 

[Spott]

Obviously, the "safest" answer is that you should maintain the original design with the correct fusible links. However, I don't like fusible links, and feel that Ford may have made a compromise to cost in using them instead of replaceable fuses.

A couple of years ago I was having trouble chasing down some electrical gremlins, so I replaced the entire fusible link assembly in my 2.9l '88 with the fusebox from a '96 or '97 Ranger. (I moved the air box back a couple inches, slid the battery over to the right side of the tray, and there's just room to mount it against the fender.) It has a 175A main fuse, and I used a number of Maxi fuses instead of the fusible links. (I also used some of the relays in the box to provide a high-beam and low-beam relay, and side-marker turn signals.)

After some calculations of load on the circuits, plus data on the fusing currents of various wire sizes (http://www.powerstream.com/wire-fusing-currents.htm), plus considering the fuses that I had on hand, I settled on using a 50A fuse for the headlight circuit, another 50A for the ignition circuit, a 60A fuse for the alternator circuit (also covers both the headlight and ignition circuits), a 30A for the fuel pump circuit, and a 30A for the EEC circuit. I didn't eliminate the fusible links for the electronic shift controls and the power door locks, because my truck doesn't have those components.

I'm not going to claim my solution is perfect, but I believe those values are a good compromise between safety and reliability (which is about the same compromise Ford had to consider in the design). If it helps your evaluation of my suggestion, I'm an Electronics Engineer, so I'm pretty familiar with the concerns involved.

Spott

 

[broncobuckinaround]

I like your idea. I could swap out the fusible for inline maxi fuses later on down the road.

 

[Stevenanderson]

I have a 1989 ford ranger 2.9 4x4 only starting and running when the sprout connecter is removed. I was researching to see if it is a fusible link. Can anyone give me an idea where might this fusible link might be between the eec and ecm. My ignition is still not working.

Any advice would be greatly appreciated on possible location. Fuse box is location on passenger engine bay panel.

 

[RonD]

I have a 1989 ford ranger 2.9 4x4 only starting and running when the sprout connecter is removed. I was researching to see if it is a fusible link. Can anyone give me an idea where might this fusible link might be between the eec and ecm. My ignition is still not working.

Any advice would be greatly appreciated on possible location. Fuse box is location on passenger engine bay panel.

No, for sure not a fusible link

No fuses between TFI module and Computer


SPOUT(SPark OUT) is the signal FROM the computer TO the TFI spark module, its for "load" spark advance, its what Vacuum Advance was for on older distributors

Distributors can do RPM spark advance on their own, pretty simple calculation

But when you accelerate, put a LOAD on the engine, the fuel mix needs to be Richer, and spark timing must be adjusted for that Richer mix
In Fuel Injected engines only the computer has the "load" information, from throttle sensor and MAP/MAF sensor
So SPOUT is used for that, it adjusts the TFIs RPM advance to suit the LOAD on the engine

SPOUT Connector is there so you can set the Base Spark timing, same as disconnecting Vacuum Advance when setting the spark timing.
You warm up the engine and shut it off
You disconnect SPOUT, before or after warm up what ever allows engine to start and run
Hook up timing light to spark plug #1
Loosen distributor a bit so you can turn it
Start engine
Set Base timing at 10deg BTDC, some prefer 12deg BTDC
Tighten distributor
Hook SPOUT back up
Start engine

Should see timing at about 20deg BTDC, +/- 2deg

If engine won't start have a helper crank the engine while you look at the timing, see how far off it is
Could be TFI or Computer issue