86 electrical issue
Thread Starter
Racer
Joined: Nov 2004
Posts: 445
Likes: 0
86 electrical issue
Car has been in storage 4 yrs.
After much prep finally got it started. Runs fine, although at idle instrument lights are lightly flickering.
After running for 10mins the car will not turn over at the same speed as when cold.
Feels like a weak battery, but it seems to be fully charged.
Changed starter, took it for a drive then dash lights went crazy...all sections lit up and engine stopped.
Waited for help and after 20mins jump started ok.
Cleaned all battery terminals, recharged battery and starts fine when cold, dash flickers and won't restart when hot.
Advice/help needed please....
Thx.
After much prep finally got it started. Runs fine, although at idle instrument lights are lightly flickering.
After running for 10mins the car will not turn over at the same speed as when cold.
Feels like a weak battery, but it seems to be fully charged.
Changed starter, took it for a drive then dash lights went crazy...all sections lit up and engine stopped.
Waited for help and after 20mins jump started ok.
Cleaned all battery terminals, recharged battery and starts fine when cold, dash flickers and won't restart when hot.
Advice/help needed please....
Thx.
Team Owner
Joined: Mar 2001
Posts: 54,124
Likes: 30
From: Cincinnati, Oh USA
Use a timing light to see if you have spark when the engine is hot and won't start. A common cause is the spark module inside the distributor. When aged, they stop or put out a weak spark when hot but are ok cold. Batteries don't, "seem" fully charged. Either they are charged or they are discharged. You determine the state of charge by measuring the no load battery voltage. 12.0 volts and lower, discharged, recharge your battery at least overnight. 12.9 volts and higher, fully charged and linear in between. Flickering lights can be due to an oscillating voltage regulator inside the alternator. Unplug the alternator and see if the flickering stops. If it stops, replace the voltage regulator or the alternator if you don't want to get inside the alternator.
Thread Starter
Racer
Joined: Nov 2004
Posts: 445
Likes: 0
Thx for the replies.
I swapped out the alternator for another one, but inadvertantly overtightened to 10mm nut holding the battery cable at the back of the alternator. When I touched the gr. lead to the -ve battery terminal there was a massive spark at the batt. terminal.
I swapped out the alt. for another known good one.
Since then the system isn't charging...less that 12v indicated on cluster.
All fuses are good...I pulled EVERYone and checked with DVM for continuity.
I checked all fusible links, incl. the one at back of starter.
Turns out this link-wire is a feed to the climate control module on top of the heater box, and doesn't appear to be connected to the charging circut..
I swapped out the cluster for another good one, thinking that this issue has to do with the brown wire at back of alt. needing a good circut to the battery warning light, in the center of the LCD cluster.
This is the ONLY battery waring light in this car.
I pulled the DIC looking for the battery warning, but there is not one in there.
I checked 2 other DIC's and none of them have this warning light.
Other than this condition the car starts and runs fine.
This no-charge has been happening since the sparking at the battery terminal...
I am at a losss...any help would be greatly welcomed.
TIA
I swapped out the alternator for another one, but inadvertantly overtightened to 10mm nut holding the battery cable at the back of the alternator. When I touched the gr. lead to the -ve battery terminal there was a massive spark at the batt. terminal.
I swapped out the alt. for another known good one.
Since then the system isn't charging...less that 12v indicated on cluster.
All fuses are good...I pulled EVERYone and checked with DVM for continuity.
I checked all fusible links, incl. the one at back of starter.
Turns out this link-wire is a feed to the climate control module on top of the heater box, and doesn't appear to be connected to the charging circut..
I swapped out the cluster for another good one, thinking that this issue has to do with the brown wire at back of alt. needing a good circut to the battery warning light, in the center of the LCD cluster.
This is the ONLY battery waring light in this car.
I pulled the DIC looking for the battery warning, but there is not one in there.
I checked 2 other DIC's and none of them have this warning light.
Other than this condition the car starts and runs fine.
This no-charge has been happening since the sparking at the battery terminal...
I am at a losss...any help would be greatly welcomed.
TIA
Team Owner
Joined: Jan 2003
Posts: 20,322
Likes: 248
From: Summerland B.C. Canada
With wires removed from alt, wires from terminal 2 and Bat should be hot and wire from terminal 1 should be hot with ignition on.
Is this what you have ?
Here is some good info from my 86 FSM
http://members.shaw.ca/agent86/Start...g%20System.pdf
http://members.shaw.ca/agent86/Charging%20System.pdf
Is this what you have ?
Here is some good info from my 86 FSM
http://members.shaw.ca/agent86/Start...g%20System.pdf
http://members.shaw.ca/agent86/Charging%20System.pdf
Thread Starter
Racer
Joined: Nov 2004
Posts: 445
Likes: 0
Thx for your interest...Yes, with all wires disconnected, I have battery voltage on both red wires with ig. off. Nothing from brown wire until ig. on, then there is battery volyage on the brown wire.
Btw...where on the car is the 510ohm resistor located...?
Btw...where on the car is the 510ohm resistor located...?
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Instructor
Joined: Sep 2005
Posts: 142
Likes: 0
From: New Jersey
I had a similar problem,,, it needed a new cable to the alternator. Their not expensive. It happened when they over tightened the cables when I got a new alternator.
Last edited by johnven; Jun 17, 2011 at 08:53 PM.
Thread Starter
Racer
Joined: Nov 2004
Posts: 445
Likes: 0
To those that offered their help....
Turned out that the problem was a bad connection at the 2 pin plug that goes into the alternator, even though I was getting correct readings off of the plug whilst diagnosing.
A spray of contact cleaner into the plug and all is well.
Thx to those offering assistance, esp. Agent.
Now I need to find the reason I am getting a high pitch noise from the back of the engine on the right hand side after driving 2-3 miles...with a burning smell like fried bacalite, and then having a seemingly flat battery as the car won't crank after shutdown....
Turned out that the problem was a bad connection at the 2 pin plug that goes into the alternator, even though I was getting correct readings off of the plug whilst diagnosing.
A spray of contact cleaner into the plug and all is well.
Thx to those offering assistance, esp. Agent.
Now I need to find the reason I am getting a high pitch noise from the back of the engine on the right hand side after driving 2-3 miles...with a burning smell like fried bacalite, and then having a seemingly flat battery as the car won't crank after shutdown....
Team Owner
Joined: Jan 2003
Posts: 20,322
Likes: 248
From: Summerland B.C. Canada
You want to have a look at the starter, maybe the pinion gear is stuck out.
Thread Starter
Racer
Joined: Nov 2004
Posts: 445
Likes: 0
Ok, all sorted finally.
When I swapped starter out for another that was working, car started ok.
After a short drive (3-4miles) the high pitched whine began.
I pulled the starter out and removed rear plate off of the housing...bits fell out all over the place.
Refitted another starter, hit the key to start...and nothing..
After many hours of testing the probelm turned out to be in the VATS.
Seems that when the other starter fried itself, it also fried the Start Enable mode in the VATS unit.
After putting a permament ground to the thin green wire between the VATS and Starter Enable relay, it fired right up.
Interestingly, the starter solenoid has two small purple wire terminals...only one, closest to the block, will provide power to the solenoid.
Took the car for a 8 mile drive and all is well ....so far.
Thx. for interest and advice...
Now to swap out rh headlite relay, as motor has stopped working.....
When I swapped starter out for another that was working, car started ok.
After a short drive (3-4miles) the high pitched whine began.
I pulled the starter out and removed rear plate off of the housing...bits fell out all over the place.
Refitted another starter, hit the key to start...and nothing..
After many hours of testing the probelm turned out to be in the VATS.
Seems that when the other starter fried itself, it also fried the Start Enable mode in the VATS unit.
After putting a permament ground to the thin green wire between the VATS and Starter Enable relay, it fired right up.
Interestingly, the starter solenoid has two small purple wire terminals...only one, closest to the block, will provide power to the solenoid.
Took the car for a 8 mile drive and all is well ....so far.
Thx. for interest and advice...
Now to swap out rh headlite relay, as motor has stopped working.....
