Results 1 to 9 of 9

Thread: Fuse, She Blows

Discussions of Triumph motor cars

  1. #1
    Senior Member
    Join Date
    Feb 2020
    Location
    Old Dominion
    Posts
    64
    Thanks Thanks Given 
    1
    Thanks Thanks Received 
    4
    Thanked in
    4 Posts

    Fuse, She Blows

    I have a circuit which keeps blowing the fuse. Not immediately, but after a short amount of driving, like it did today. It's the second fuse from the top inside the engine bay box, and it takes out the turn signals, a couple of gauges and lights and other stuff too I'm sure. Question is, how do I track down the culprit? I'm suspecting it's related to the turn signals, just a guess, but I did do some work on the tailights somewhat recently. And when I looked down today and noticed the gauges were out again, I had been sitting a light with my right signal on for a minute or two.

    Help, oh Triumph Overbrain!
    Martin
    '72 TR6

  2. #2
    Yoda poolboy's Avatar
    Join Date
    Oct 2007
    Location
    S.W. Mississippi
    Posts
    3,821
    Thanks Thanks Given 
    25
    Thanks Thanks Received 
    26
    Thanked in
    25 Posts

    Re: Fuse, She Blows

    That sounds like the fuse for the 'green wires' circuits.
    You should have a schematic.
    http://www.advanceautowire.com/schematics.htm
    DRIVE 'EM IF YOU GOT 'EM

  3. #3
    Senior Member
    Join Date
    Jul 2020
    Location
    Fernley,NV
    Posts
    76
    Blog Entries
    2
    Thanks Thanks Given 
    0
    Thanks Thanks Received 
    2
    Thanked in
    2 Posts

    Re: Fuse, She Blows

    There are a few ways to find your problem. If you feel it is in the signals switch. that would be easy don't use it NO No! is it left or right? all the wires travel under the steering column Light green is com. green and white right turn green and red left turn that would be first test . All these wires are hot or would be if turn sig is on. The column has a cover over wires first place to look. With the turn sig on bang the steering wheel left then right. ( NOTE to save fuses make a jumper with a lite socket and bulb. and put across the fuse pinch wires in with fuse to hold wires. fuse good or bad no matter ) The light will glow if short is made You should be able to see lite while banging wheel. CAUTION do not over size fuse. If you have only worked in the boot and find that it is say only left turn and you have the covers on remove and check same. All wires come from the drivers side so the right side is most likely OK. All wires run next to the drivers seat along door sill. If a wire is pinched it could be years for a problem to show. Work on seats carpet any thing on drivers side ?? Under the dash is more work wires either go to rear of car or inst. or from the fuse box. If you added a new radio look there and at gauges. If a gauge light has fall out it could be banging around under dash. It is not likely a side lights have a ground. Madflyer

  4. #4
    Senior Member
    Join Date
    Feb 2020
    Location
    Old Dominion
    Posts
    64
    Thanks Thanks Given 
    1
    Thanks Thanks Received 
    4
    Thanked in
    4 Posts

    Re: Fuse, She Blows

    Thanks Madflyer. I like the light bulb idea. I'm just guessing it's associated with the right turn signal, which is what I was using last time out when I noticed the fuse had gone out. The strange thing to my little electrical mind is that all the signals and lights work as they should when the fuse is not blown. Is that normal?
    Martin
    '72 TR6

  5. #5
    Obi Wan Sarastro's Avatar
    Join Date
    Jul 2006
    Location
    Long Beach, California
    Posts
    2,383
    Thanks Thanks Given 
    1
    Thanks Thanks Received 
    12
    Thanked in
    12 Posts

    Re: Fuse, She Blows

    If I were doing this, I'd remove the fuse in question and connect a high-value ammeter. Then watch it as you turn things on and off, jiggle wires, and so on. Watch for a current that is close to or above the fuse's current rating. It's likely that something, somewhere, is making a momentary short circuit, because of a loose connection or damaged wire.
    Steve Maas
    1966 Triumph TR4A, undergoing restoration: http://www.nonlintec.com/tr4a
    1952 MG TD, restoration completed 2014, sold 2016: http://www.nonlintec.com/mgtd
    1960 Austin-Healey "Bugeye" Sprite, sold 2010: http://www.nonlintec.com/sprite
    1967 Porsche 912: http://www.nonlintec.com/porsche

  6. #6
    Senior Member
    Join Date
    Feb 2020
    Location
    Old Dominion
    Posts
    64
    Thanks Thanks Given 
    1
    Thanks Thanks Received 
    4
    Thanked in
    4 Posts

    Re: Fuse, She Blows

    Actually I think I found the problem. What amp rating are these fuses supposed to have? Should they all be 35, or are they different ratings for different circuits.
    Because in my fuse box I have 20, 30 and 35 amp fuses. The 20 amps are the replacements I've been using. (Thankfully in 20+ years of owning this care I have had almost no electrical issues. Of course 'those Lucas electrical problems' are the first thing quasi-knowledgeable people say to me when they learn about my TR6, but it's just never been an issue for me).

    Point is - the fuse that's been blowing is on the circuit to which I added an electric puller fan recently, and I've been using a 20amp fuse there. So I'm going to up rate it to 35amps. I presume the circuit's been blowing when the fan kicks in for very long. Add a turn signal to the fan's draw and boom, probably out goes the fuse. Don't we think?
    Martin
    '72 TR6

  7. #7
    Obi Wan LarryK's Avatar
    Join Date
    Mar 2007
    Location
    Millstadt, IL
    Posts
    2,123
    Thanks Thanks Given 
    0
    Thanks Thanks Received 
    27
    Thanked in
    26 Posts

    Re: Fuse, She Blows

    Probably should wire a circuit just for the fan instead of overloading the wire for the 20W. Don't need a fire in the baby.
    Larry K
    58 Jag 3.4 MK 1 auto under restoration, 57 Jag 3.4 MK1 manual (parts car),
    03 Cooper S, 2011 Cooper S Countryman, 2011 Land Rover LR4 HSE LUX, 1964 Valiant V200
    Also had , 68 Cortina 1600E, 64 Spit 4 & 80 1500, 73 GT6 3, 71 XJ6, 79 XJ6, 86 XJS V-12, 53 XK120 OTS.

  8. #8
    Senior Member
    Join Date
    Jul 2020
    Location
    Fernley,NV
    Posts
    76
    Blog Entries
    2
    Thanks Thanks Given 
    0
    Thanks Thanks Received 
    2
    Thanked in
    2 Posts

    Re: Fuse, She Blows

    Martin The horn has the larges value fuse I think 20 A. The rest are 1/2 that value. The addition of any electric item fans fog lights etc. should be on new circuit and run by a relay. I removed the glass fuse holder and went to a new blade style fuse and also split my circuits and now have room for 5 circuits one is a spare. also the blade fuses have ones that glow when blown and are easy to read value and color too. If you are still running the Lucas Alt it is only 43 Amps. So lights on, fan on, turn sig on, radio on that adds up quickly. Many have gone to 63 Alt easy to do. I also added a Sig. lighter straight from battery with it's own in line fuse for a USB plug for my TOM TOM GPS. Are cars were built at an earlier time and may not have even been driven at night or rain fans, heated seats, lights, amps for radios were never in UK thinking. All added items can be installed cleanly and or out of sight Items like LED lights in dash brake and tail lights will be brighter an less Amps. Remember size matters that includes wire and fuse. Madflyer

  9. #9
    Senior Member
    Join Date
    Feb 2020
    Location
    Old Dominion
    Posts
    64
    Thanks Thanks Given 
    1
    Thanks Thanks Received 
    4
    Thanked in
    4 Posts

    Re: Fuse, She Blows

    Not a Lucas alternator, that one gave up the ghost a few years ago. It's replacement is a Remy reman'd unit, rated at 55 amps. Just now learning that a Lucas '35A' fuse is actually something a bit more than 20amps, correct? That's the fuse I moved to the fan circuit for now and it seems to be holding.

    I appreciate the suggestion to move the fan to its own circuit; I'll work on that. I also understand that Dan Masters suggests that the 'red' circuit (bottom fuse) ought to have a 10amp(AGC) fuse, the purple 15amps, and 20 for the white. I'll be doing that too. Thanks folks.
    Last edited by Martin Secrest; Today at 08:27 AM.
    Martin
    '72 TR6

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •