Burnt altenator and solenoid

Gotta love that wiring . . .
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TJenkins
Posts: 19
Joined: Fri Aug 29, 2014 3:15 pm
Your car is a: 80 Fiat Spider

Burnt altenator and solenoid

Post by TJenkins »

Smoking altenator. Bit of a long story. My starter went in that when I turned the key nothing. After trying different things had starter rebuilt including the solenoid. Sat for a year before installing the starter, battery dead, not taking a charge. Bump started the car, ran fine. Got a new battery started the car and smoke coming from the altenator. Now when I turn the key nothing, (just checking if the solenoid is fried again and it appears to be the case). So it looks like a rebuild of solenoid and altenator but the bigger question is what is the root cause??
And yes the battery was connected correctly, even tested it with a volt meter. Any suggestions on what to check??

Thanks in advance.
spider2081
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Your car is a: 1981 Spider 2000
Location: Wallingford,CT

Re: Burnt altenator and solenoid

Post by spider2081 »

And yes the battery was connected correctly, even tested it with a volt meter.
Connecting the battery reversed even for an instant usually causes the alternator diodes to short (fail)
At any rate once the alternator fails it is usually a very large load on the battery. I would disconnect the battery negative terminal. Then disconnect the alternator's output wires, use a bolt to connect the removed wires ring terminals together and then tape the connection so it can't short to anything. Recharge the battery and reconnect the negative terminal. Try and start the car. Maybe the defective alternator is loading the system so much the starter can't engage.
TJenkins
Posts: 19
Joined: Fri Aug 29, 2014 3:15 pm
Your car is a: 80 Fiat Spider

Re: Burnt altenator and solenoid

Post by TJenkins »

Thank you very much for your response. Funny you should mention that cross connecting for even an instant can fry the alternator. My brother was being helpful and connected the new battery but unfortunately he assumed the posts were oriented the same as there were in the previous battery (with the post side facing out of the trunk positive on the left) and connected the battery accordingly. When he touched the ground wire to the battery big spark so he decided to actually look at the battery markings and realised that he had them reversed :cry: . So from you have said that was probably the instant that the diodes fried. I will try what you have suggested and see how it goes.

Thanks again, stay tuned,
Thomas
TJenkins
Posts: 19
Joined: Fri Aug 29, 2014 3:15 pm
Your car is a: 80 Fiat Spider

Re: Burnt altenator and solenoid

Post by TJenkins »

Update:I disconnected the alternator as suggested and tried starting the car and nothing. Same symptom as when the solenoid was fried. I've pulled the alternator off and will drop it off to be rebuilt. As for the solenoid, going to order a new one and put it on myself.

My concern is that will be the third time replacing the solenoid. With this last occurrence I'm assuming that the blown alternator was the cause of the failure. However, before I try again I really want to check the system to ensure that I'm not doing this for a fourth time (although I am getting faster at pulling and re-installing the starter). Any suggestions on how I can validate the system would be greatly appreciated.

Regards,
Thomas
spider2081
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Your car is a: 1981 Spider 2000
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Re: Burnt altenator and solenoid

Post by spider2081 »

Update:I disconnected the alternator as suggested and tried starting the car and nothing. Same symptom as when the solenoid was fried.
The 2 wires your removed froth e alternator output post have to be connected together and then insulated (taped) for the ignition coil to be powered.

Starter solenoids are pretty strong units. The contacts can wear out over time but that usually takes years. I can't think of anything that would "fry" a solenoid other than a shorted starter motor.

When you turn the key to the start position and the starter does not spin do you have battery voltage on the small red wire with the push on spade connector?? The other wires for the solenoid have ring terminals and go on the solenoid battery terminal.

Your problem could be associated with the ignition switch system.
TJenkins
Posts: 19
Joined: Fri Aug 29, 2014 3:15 pm
Your car is a: 80 Fiat Spider

Re: Burnt altenator and solenoid

Post by TJenkins »

When I removed the wires from the alternator I bolted them together and insulated them as suggested. Turned the key and nothing at all.

This is actually the 3rd solenoid that I've gone through with the last two lasting a couple of starts each. The first went and I assumed it was just a failure due to age and wear. The second one went after a few starts, when I was taking it off I noted that one of the smaller wires was only making intermittent contact with the solenoid post. This combined with the a weak battery led me to the assumption that the cause was low voltage due to my screw ups. This last time, as I mentioned the new battery was connected in reverse polarity and although only for a very brief second it appears to be enough to burn out the diodes in the alternator. The car was started once prior to realising that the alternator had been damaged. The alternator was smoking and was far too hot to touch. Subsequent attempts to start the car resulted in with absolutely nothing happening when the key was turned, same symptom as previous solenoid failures. To be honest I did not go to the extent of measuring the voltage at I jumped to the conclusion that it was the same issue a the last two occurrences.

I took the alternator and starter to the rebuild shop and the guy was surprised when I mentioned that the solenoid had failed again. He is going to check it out and replace if necessary.

In summary, I'm assuming the last two solenoid failures are due to human error (1st - poor connections & week battery, 2nd - burnt alternator). However, I don't want to proceed with the assumption that once the components are repaired and reinstalled all will be good, prior to validating the integrity of the system and I am not sure on how to do this.

Thanks for your patience in reading my novel,
Thomas
spider2081
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Your car is a: 1981 Spider 2000
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Re: Burnt altenator and solenoid

Post by spider2081 »

If you are not getting the "dreaded click" no start I suspect something prior to the starter solenoid. On your car there are 2 single bullet connectors in the area of the back of the alternator near charcoal canister One is in a heavy brown wire and one in in a red wire. The brown wire single bullet conector brings battery voltage to your ignition switch from the battery post on the starter solenoid. The red single bullet connector brings the "start" voltage from the ignition switch to the starter solenoid to make it engage. Check to see that they did not come loose or get disconnected. They are a common issue with your year car.
TJenkins
Posts: 19
Joined: Fri Aug 29, 2014 3:15 pm
Your car is a: 80 Fiat Spider

Re: Burnt altenator and solenoid

Post by TJenkins »

Thank you for the advice, I haven't looked at these connections. Picking up the starter and alternator from the repair shop this week, I will post the outcome.

Thomas
TJenkins
Posts: 19
Joined: Fri Aug 29, 2014 3:15 pm
Your car is a: 80 Fiat Spider

Re: Burnt altenator and solenoid

Post by TJenkins »

Installed the rebuild alternator and the starter and nothing. No click, no nothing! Located the two bullet connectors and yes they were oxidised. Cleaned them up and tried again and I was now getting a click at the solenoid. Progress! Cleaned and tightened the spade connector for the hot wire on the solenoid and ...... the freaking thing started!!!!!! Did my happy dance in the driveway for about 10 minutes doing fist pumps. This has been 2 years of grief as I have had very little time to work on it. I actually got so frustrated I tried selling it but changed my mind (had enough of tire kickers and low ballers). Insurance and license tomorrow and I will be back on the road! Thank you all for your advice and for Spider2081 pointing me to the bullet connectors. More happy dancing....
TJenkins
Posts: 19
Joined: Fri Aug 29, 2014 3:15 pm
Your car is a: 80 Fiat Spider

Re: Burnt altenator and solenoid

Post by TJenkins »

Well my celebration was short lived...

(recap) I've been having issues with my solenoid going so in the process of tracking down the problem I purchased a new battery and yes connected it in reverse. Had the alternator rebuilt and the starter checked (it was fine). Put everything back together and nothing. Cleaned the connections at C6 (two bullet connectors by the alternator). At least now I was getting a click when I tried to start it. Pulled the hot wire going to the solenoid cleaned it and yes it started!! Started it a few times and worked perfect.

Ok so renewed the license sticker, put insurance back on it and jumped in to take my first drive in almost two years and nothing but a 'click'. Checked all connections good. Voltage going to the solenoid 12v. Charged the battery thinking it could be a parasitic drain, still nothing. Really at a loss. One thing that I am thinking is to install a new ground cable from the motor to the body... grasping at straws. Or on second thought maybe a can of gas and a match.

Thomas
ORFORD2004
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Joined: Wed Mar 17, 2010 9:48 pm
Your car is a: 1983 PININFARINA
Location: Sherbrooke, Qc, Canada

Re: Burnt altenator and solenoid

Post by ORFORD2004 »

Clean your ground in the trunk. Switch is easy to check. brown wire bring + from the engine bay to the switch. Check the connector near the switch with a test light to see if you have + on brown wire. If yes, check red wire at the same connector with key on start to see if you have +. Check both side of the connector for the red wire since that connector is often bad. Also if you have to repair your starter, change it with the lighter and faster unit.
TJenkins
Posts: 19
Joined: Fri Aug 29, 2014 3:15 pm
Your car is a: 80 Fiat Spider

Re: Burnt altenator and solenoid

Post by TJenkins »

The car is running, all issues resolved. This is what I did:
- New battery
- Removed plastic connector C31 and connected the spade connectors directly
- Put in a relay for the hot wire to the solenoid.
- Cleaned the brown wire connection at C6 (used the red wire at C6 to goto the relay).
- Rebuilt starter which included a new solenoid (fried solenoid was probably due to low voltage caused by bad connections at C6)
- Rebuilt alternator (self inflicted wound by hooking up new battery in reverse)

In retro spec I believe the biggest issue was the brown wire connection at C6. I peeled back the insulating tape at the ends and found the wire to corroded. Once I cleaned that connection thoroughly and pinched the connector to create a tighter fit I had no more issues (mind you I had done all of the other items mentioned above.).

So It's on the road and I'm now an expert in removing and installing the starter - but never again.

As always, I appreciate everyone's guidance.

Thomas
spider2081
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Re: Burnt altenator and solenoid

Post by spider2081 »

when great news is really great. Congratulations for not giving up now enjoy your car
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