'81 FI Spider won't start with lights on....

[alsgro]

Hi, all.

I've been putting this off way too long now. Time to actually deal with this.

I'll start by saying that my battery seems in good nick. Voltage looks good on the multimeter, and AZ confirmed it has good cranking amps...

The problem is that 9 times out of 10, the starter won't even engage with the lights on. If I drive the car home at night and try to start it in the morn with the light switch down (on), I get nothing when I turn the key except maybe a barely audible click. I can hear the fuel pump going, and all the dash lights come on normally, but no vroom. I turn the switch to off, and she fires right up.

It's unnerving to say the least, and I'm worried that I'll get stuck somewhere one day. Any ideas??

Thanks!
-aL

[courtenay]

Turn the lights off before you try and start the car? The starter takes a lot of juice and so do the lights.

[spider2081]

Have you checked the engine to chassis ground braid. It is located near the starter and is welded to the under side of the drivers floor.
Have you inspected the ignition switch connector for loose?corroded/burnt female terminals??
Have you checked the spade connector on the solenoid that for good connection.
Have you checked the single terminal bullet connection about 6" forward of the starter in the red wire?

Any of these or a combination of them could contribute to your symptom

[narfire]

I'll start by saying that my battery seems in good nick

Wonder if the steering wheel is on the wrong side..

Perhaps check the connections at the battery. I had poor starting performance once and the ground connection was loose/poor.
Turn the lights off would help as mentioned..
Chris

[redcars]

Having the lights on should not make a differance if the battery is good. I run with my lights on and never turn them off. I don't have a problem stating. I think the advice you have gotten so far is good check for poor connections and poor grounds. I wish I could be of help, but I have not had this problem yet.

[SLOSpider]

Sounds like you may have a voltage drop due to High resistance in the wires. The Brown wire fix was a good cure for this for the older cars. Best thing to do is clean the contacts at the starter, connections and at the switch connections. I would start with seeing how much voltage you have at the starter with the lights on and trying to start it. Running a dedicated wire to the starter and ignition is sometime the best fix.

[vandor]

>Have you checked the engine to chassis ground braid.

I always add an extra ground strap, just to be sure.

[courtenay]

No need for the brown wire fix on an '81. It's already there.

[spider2081]

I agree with adding a second ground.
I went to change the starter on my son-in-laws 1980 and although the ground strap looked good it was so brittle it snapped in two when I tried to move it out of the way.
Sometimes I see this ground connected to the flywheel cover. I think it is suppose to be connected with one of the starter bolts.

[SLOSpider]

An easy way to check to see if its a ground problem is with jumper cables.You can connect one black lead to the engine and the other to neg side battery or vody if cables are to short. Retry to start and see if it helped. If it starts better then you want to start checking your ground wires from battery forward.

[alsgro]

Thanks, guys for all the thoughts!! I'm going to be poking around today and trying to fix the issue.

Am I right that trying the brown wire fix on an '81 is redundant because there's already a wire running from the starter straight to the ignition?

I also bought a new thermo time switch from Allison's automotive today. Apparently, I got the last one in existence, because calls to Internation auto and Vick Auto turned up nada! Anyway, installing that is also on my list today, so wish me luck!

Thanks again for the input, all. I'll let you know how it goes.

[courtenay]

As noted in my earlier post, the brown wire is already there.

[vandor]

>An easy way to check to see if its a ground problem is with jumper cables.

Or a voltmeter. If there is more than 1 volt between the engine ground and body ground during cranking, then there is an issue.