electrical gremlins

[Polly-Red7]

Hi one and all,
My 7 seems to have fallen foul of the gremlins this weekend! It's been off the road for a while due to water in the tank, which now fingers crossed has been sorted and an additional two fuel filters added to stop the gunge!
However, today without warning I have no lights except indicators, no windscreen washer but have wipers? No interior lights in either the cabin or boot? No horn, oh and the clock has stopped? I'm presuming with my severe lack of electrical prowess that it must be grounding out somewhere, but a look at the wiring diagram has left me none the wiser!? Any ideas anyone? Many thanks in advance,
Chris

[scarface031]

Check the fuses before you do anything else. I know on my car I had a problem with all of that, and the clamps were loose on the fuses. I just took a pair of needle nose pliers and clamped them together and this solved my problem.

-Justin P

[FI Spyder]

With 30+ years and open electrical connections there is ample opportunity for corrosion/oxidation of the many electrical connections the car has. You can fix one at a time with the result that you will be chasing one electrical gremlin or another at usually inconvenient times. Or you can go through the car on a convenient weekend/winter project and clean every one with contact cleaner and brush (etc) and apply a little dielectric grease to make the car reliable in sunshine and driving rain storm. I chose the later and other than the starter relay connector block which has been stubborn (maybe I've got it now) my car has been reliable is those conditions.



- - -TR7 Spider - - - 1978 Spitfire- - - - 1976 Spitfire - - 1988 Tercel 4X4 - Kali on Integra - 1991 Integra - Yellow TCT

[Polly-Red7]

Thank you for your replies, thankfully it turned our to be a faulty spade connector at the battery end, phew panic over!

[Chunkychops]

I've had the gremlins since I bought mine about 4 years ago. The latest problem started today. My petrol gauge has never worked so I used to rely on the warning light but that stopped working when I put a new petrol tank sender unit in (which made no difference), so now I put petrol in once a week and hope it lasts.

This evening I put £25 in and on leaving the garage, noticed that the fuel warning light was working again, but only when I indicated left.
The coolant light keeps coming on even though its full, the headlamps used to switch off for no apparent reason. And I had to remove the original stereo from the car because it used to switch itself on whenever it felt like it, even with the ignition off.

Temperature gauge doesnt always work, clock stops and starts and when it does work gains about half an hour a week. Brake lights and reversing lights intermittent, interior door lights unreliable.

Other than that shes fine [xx(].



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[Hasbeen]

Come on Chris, no secrets here. What did you do to fix the water in the tank problem?

Hasbeen

[alc59]

Forget about the clock timekeeping - rubbish is normal!
Al

[FI Spyder]

<blockquote id="quote"><font size="1" face="Century Gothic, Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by alc59</i>

Forget about the clock timekeeping - rubbish is normal!
<hr height="1" noshade id="quote"></font id="quote"></blockquote id="quote">

Never had any problem with mine. I do have to adjust it a couple of times a summer though.

- - -TR7 Spider - - - 1978 Spitfire- - - - 1976 Spitfire - - 1988 Tercel 4X4 - Kali on Integra - 1991 Integra - Yellow TCT

[76tr7rules]

I spent a little time studying the electrical Diagram. Hopefully your car is US spec. Check to make sure you have 12 Volts on the brown wire at the ignition switch. I traced all the circuits back that are having trouble, and the brown constant power wire from the ignition switch feeds all of them in one way or another.

By the way old style diagrams like the Triumph's are difficult to follow. The trick they taught us back in the day is to print out a few copies of the diagram. Then use a pack of colored pencils and trace out each section of wire. I look for the feed to each one and trace it back to the source with one color. Then do each leg of the switch with one color. If I had more colored pencils I would take a picture and put it up so you could see.

So right now I know the second pin on the right of your headlight switch and the 2nd pin on the left are both fed by the circuit form the ignition switch. From there the bottom left pin feeds 2 fuses then goes to all your marker lights. Your bottom right goes to the dimmer blinker switch and then it comes out goes to the headlights, and right side light. Also one pin from the signal and dimmer switch feeds the clock.

Next the brown wire splits and enters the horn relay, and the courtesy lights

[Polly-Red7]

Hi everyone,
Been off the grid for a while! The electrical gremlin turned out to be nothing more than a bad connector at the battery end (the big 4 way job). The water in the tank is now out after fully draining it by removing the sender unit and siphoning another 3 litres out! However that has taken its toll on the tank and it is now weeping fuel from the circular seam around the sender unit! Never rains but drips fuel! So I'm after a temporary fix whilst I source a decent replacement tank. Ideas anyone? Also having fun and games with the timing,although fingers crossed that will be sorted tomorrow. Then if there's any justice a clean bill of health and a MOT certificate!

[nick]

Don't know if you have JB Weld available in your country. If not you must have something similar. The product I would use comes in a stick. It is two part epoxy. You just break off the amount you want to use. Kneed it to mix the two parts and apply it with wet fingers. It is impervious to gas and oil and could become a permanent fix. It sets up pretty quick so work fast. I have used this stuff on my tank and also on my water pump cover.

[img][IMG]http://i615.photobucket.com/albums/tt234/nickmi/TR7%201975/Yellow.jpg[/img]
nick
'79 TR7 DHC
'76 TR7 FHC

[Hasbeen]

Hi Chris. I had the same thing happen a couple of years ago. I had previously repaired the tank when it started rusting through from the inside. I had cut a 4" wide strip out of the bottom front of the thing, & welded in new metal.

When it started leaking from the sender fitting 10 years later, I tried Nicks fix, with no success, it still wept a little. The thing appears to be silver soldered & spot welded in, either that, or the surface coating they apply inside seals it.

The POR 15 treatment may seal it, but unsure how they built the thing, so not knowing how to repair it, I bit the bullet & bought a new tank. At $600 for one in Oz, it was expensive, but should be the final tank job for me.

At least the leaking tank cleared up a problem. My fuel consumption had slowly climbed from a bit over 8L/100Km to almost 14L/100Km. I had spent quite some time looking for a tuning problem causing this.

While fitting a new fuel hose, the tank looked a different colour around the fitting, but I still didn't tweak the problem. It was only when doing up the hose clamp that the fitting started to drip that I saw the light.

The fitting had been weeping for some time, but not enough to drip. The fuel was evaporating off, giving me my high usage.

I did think about silver soldering it, but decided I am not really good enough to do such a job reliably.

AS most of our original tanks have rusted through from the inside by now, I would not even consider fitting a used tank. Too much work, with little chance of lasting any time.

Hasbeen

[Polly-Red7]

Well I seem to have sorted the timing hurrah! Tomorrow for the tank and another leak! This time on the petrol pump, hopefully it's only the seal and I quick fix, we're running out of good weather here
Thanks for all the advice by the way, even after 3 years of 7 ownership I'm still a novice!

[Polly-Red7]

Pump leak fixed, a rotten washer to blame, tank fingers crossed, test flight to follow

[Polly-Red7]

Pump leak fixed, a rotten washer to blame, tank fingers crossed, test flight to follow