Help please Fuse popping

[Deanofire]

Does the fuse blow when it’s put in or when ignition turned on?

when i turn the ignition to 1 possition

 

[Deanofire]

Instead of wasting loads of fuses wire a bulb across the fuse terminals. Bulb will light whilst there is a short to earth and go out when you disconnect the source of the short. Disconnect anything passing through that fuse one at a time to eliminate. If nothing extinguishes the light it’s time for a wiggle test on all areas of wiring harness you can get to. Possible wire shorted to earth.

thanks thats a good idea will give that a go

 

[Deanofire]

Instead of wasting loads of fuses wire a bulb across the fuse terminals. Bulb will light whilst there is a short to earth and go out when you disconnect the source of the short. Disconnect anything passing through that fuse one at a time to eliminate. If nothing extinguishes the light it’s time for a wiggle test on all areas of wiring harness you can get to. Possible wire shorted to earth.

Good idea thanks for that

 

[Rob65]

I haven’t looked at the wiring diagrams so don’t know if this is logical but it’s a quick and easy check.
Have you tried disconnecting the alternator? When the regulators in alternators fail they can give a short circuit to ground.

 

[V8Druid]

I haven’t looked at the wiring diagrams so don’t know if this is logical but it’s a quick and easy check.
Have you tried disconnecting the alternator? When the regulators in alternators fail they can give a short circuit to ground.

very good shout Rob

 

[Deanofire]

I haven’t looked at the wiring diagrams so don’t know if this is logical but it’s a quick and easy check.
Have you tried disconnecting the alternator? When the regulators in alternators fail they can give a short circuit to ground.

Wool that be connected at position 1 on the key though?

 

[Gecko]

When the regulators in alternators fail they can give a short circuit to ground.

That's true, but the main output terminal is always hot to the battery. The charge lamp on the dash is switched , but it's low current and won't blow fuses.

@Diggerdavey suggestion of a lamp is very good. If you choose the lamp carefully, you can use it to judge the current (you may need a 5W and a 50W lamps to cover a wide range of current)

Is now a good time to suggest re-settable fuses?

 

[Deanofire]

That's true, but the main output terminal is always hot to the battery. The charge lamp on the dash is switched , but it's low current and won't blow fuses.

@Diggerdavey suggestion of a lamp is very good. If you choose the lamp carefully, you can use it to judge the current (you may need a 5W and a 50W lamps to cover a wide range of current)

Is now a good time to suggest re-settable fuses?

View attachment 34184

will give the alternator disconnect a try anyway , and i dont think they make the re settable fuses in 40A but thanks anyway

 

[V8Druid]

That's true, but the main output terminal is always hot to the battery. The charge lamp on the dash is switched , but it's low current and won't blow fuses.

@Diggerdavey suggestion of a lamp is very good. If you choose the lamp carefully, you can use it to judge the current (you may need a 5W and a 50W lamps to cover a wide range of current)

Is now a good time to suggest re-settable fuses?

View attachment 34184

did consider this the other night ..... long term though is it worth the investment ,although not astronomic .. once sorted?

 

[V8Druid]

will give the alternator disconnect a try anyway , and i dont think they make the re settable fuses in 40A but thanks anyway

Pardon our interruption...

 

[Diggerdavey]

Pardon our interruption...

The beauty of the test light method is you don’t have to keep resetting it. If it’s on there is a short. Wiggling wires (if it is a loom short) will allow the light to flicker if you move a loom that’s shorting. A resettable fuse has its place but I think in this instance a bulb would prove less frustrating during the testing process.

 

[Deanofire]

Pardon our interruption...

Think they are maximum fuse size. Mine are standard

 

[Deanofire]

The beauty of the test light method is you don’t have to keep resetting it. If it’s on there is a short. Wiggling wires (if it is a loom short) will allow the light to flicker if you move a loom that’s shorting. A resettable fuse has its place but I think in this instance a bulb would prove less frustrating during the testing process.

Am with the digger now. Have used a test lamp and when I turn ignition to pos 1 I hear the fuel pump running as it would but the bulb glows and dims so I cant really leave it connected . Any idea what else to disconnect?

 

[V8Druid]

Think they are maximum fuse size. Mine are standard

put it on flying leads, somewhere convenient??

 

[V8Druid]

Am with the digger now. Have used a test lamp and when I turn ignition to pos 1 I hear the fuel pump running as it would but the bulb glows and dims so I cant really leave it connected . Any idea what else to disconnect?

try the pump for starters and see what happens with the lamp

 

[Deanofire]

Disconnected power and plug to alternator and still the same. Am really running out of ideas now

 

[Deanofire]

put it on flying leads, somewhere convenient??

Sorry I dont understand. I am really out of my depth here. Sorry

 

[V8Druid]

Sorry I dont understand. I am really out of my depth here. Sorry

run a pair of leads of suitable size from the existing fuse point to the new resettable and locate the new resettable some where convenient

 

[Deanofire]

Right. Tank lifter pump and small silver top fuel pumps disconnected but I have a clicking on and off like an indicator noise coming from the pump area of the engine when I connect the lamp again and it's still flashing

 

[Deanofire]

run a pair of leads of suitable size from the existing fuse point to the new resettable and locate the new resettable some where convenient

But I dont have a re stable fuse. Just the test lamp