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240 Really wacky issues on my 88 (again)

Johnnya101

Member
Joined
Jul 12, 2017
Hi guys,

Had some starting troubles. Replaced the fuel relay, it turns out to be that.

That was last Wednesday. Today took it out to get something to eat, and noticed the high beams weren't working! At the restaurant, noticed that high beams suddenly worked... Hour later, came out, and it just did not want to start. Let it rest a second, tried again, and it started. High beams worked. Pull out of parking lot, and you guessed it. No high beams. Made it home.

Noticed... Yup. High beams work when moving very slowly and or parked, but only sometimes. When I pull back the lever when driving, for example, the low beams do not do anything. Just no high beams. When at home and parked, I noticed that I hear a quiet thumping sound when pulling the lever, and then when it decideds to work, the usual loud click, the indicator comes on, and high beams work.

But here's where it gets even stranger. I shut the car off after I was done with my tests, and something told me to try starting it again. Turn the key, a sound like almost like a completely flat battery. Doesn't even turn over. Kind of makes a quick part of a whirring sound. Exactly like a completely dead battery. I also noticed that when the car was running, I tested the four way hazards and the dome light dimmed whenever the signals blinked. Also, headlights have always been pretty dim. New lenses and bulbs. I've always been thinking that they were just out of alignment... But maybe it's related. Does this all sound related to you guys? No start... Wonky high beams... Dimming lights... Almost like there's no power. Battery tested and good.

Don't know where to start. Kind of need the car this week but this sounds like it will be a big issue.
 
assuming 240?

sounds like bad ground(s)

the no-start could also be the neutral lockout switch misaligned (if an auto)
 
Yes, 240. I put it in the 240 classification but should of put it in the title...


I will check grounds today.

I will look into the safety switch. Would a misaligned one cause it to make that very quick sound but no turn over?
 
Ok, heres an update.

Read the battery voltage. 11.9 volts! No wonder it wasn't turning over at all. Jumped it and let it sit idling. The battery read 13.3 volts idling.

Left it running for 20 minutes. Checked battery again. 14 volts. So it seems to be charging okay...? Shut it off and checked battery. 12.88. seems good to me.

The alternator belt appears to be the wrong style and is cracked, and doesn't appear to be tight. Could it just be slipping at any other high rpm causing the battery not to charge? Have some spares ready to install, luckily. Could it be something else? I'll check the battery again in an hour to see if it's draining. I'll try and change the belt today.
 
Voltage doesn't test battery state of charge/ "life". I use a high end digital battery analyzer. I see batteries all the time read up in the 12v range that are no good.

Your alternator also could be failing. Or the wiring. Especially the ground wire.

Do voltage drop tests. Look up how to do them. I check cables all the time with voltage drop tests. I wouldnt wanna see more than 200 millivolts drop on any of the circuits.
 
I brought the battery to Napa and had them test it last week. They said it was in excellent shape. I'll start doing a few more tests...

Update as of 2 or so hours from jumping it

Battery now seems to be a stable 12.42 volts.

Summary of findings so far...

Battery was dead after driving a few miles at night with lights on. Got home, battery dead at 11.9 volts. Jumped it and got it running this morning. Alternator first read around 13.3 volts. After 20 minutes, it increased to 14 volts.
Immediatley after shutting off, battery was 12.88 volts.
After 1 hour of the car being off, 12.44 volts.
After 2 hours, 12.42.

It seems like the battery has fully "rested" and seems to be holding a charge now.

The alternator belts definitely need to be replaced. They are kind of loose, wrong style, and all around rough and cracking. I'll start by getting the charging system gone through and tested at a shop and go from there.

Edit again

Tried spinning the alternator by hand. I can put a light amount of force and it spins. Sounds like it's the old belts.
 
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Here is a headlight step relay diagram courtesy of Dave Barton: http://www.davebarton.com/pdf/headlightsteprelay.pdf
If you notice any wires that doesn't look right, unhook the negative terminal of the battery before disconnecting this switch, as the metal cap can pop off and touch the coils inside and start an electrical fire.
http://www.davebarton.com/pdf/headlightsteprelaymockLATCH.pdf The second page of Dave's pdf has a simplified wiring diagram as well.
The thumping noise you heard might be a sign of either one of the relays starting to fail by trying to latch?

Here is a picture of the other relay which should be on the driver's side under the steering wheel by the carpet.
http://www.240turbo.com/relay-K.JPG

How is the fuse?

You could also take the switch off of the steering wheel, clean up the terminals and ground, and do a visual inspection of all of the wires.
 
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Hi all again,

Got the belts replaced finally last week. It seemed to fix my issues... But not quite.

I'll give an example of what's going on.

Charged battery manually to 100% with a charger. Installed new wbeltd (old were very loose and burned and charred from slipping).
Drove it a bit
Parked
Battery read 12.8

Day 2
Checked battery voltage. 12.7
Drove a bit
Parked

Day 3
Checked battery voltage. 12.6
Drove a bit.
Parked

Day 4
Checked battery voltage. 12.5
Drove a bit.
Parked

Day 5
Checked battery voltage. 12.42 (today)

Now it's clear that there is an issue, and it's not just the battery resting. Battery was tested great at Auto part store.

Battery voltage is steadily dropping. But why? Alternator outputs correct charging voltage (when reading from battery terminals). Belts are new. Alternator spins freely... It's almost like under load it's not charging or something? If something was draining it, wouldn't the alternator charge it back up to 12.8?

Very odd issue... No idea where to go next.

I'll also add that 50% of the time headlights are on with radio. The other 50 it's just the radio. I drive it a few miles every day, and let it warm up 10 minutes idling. So it should have plenty of time to fully charge...? Not a huge load on it either.
 
It is normal to see some internal leakage in a battery.
That is why Float chargers are sold.

There is also the clock and other electronics that will create some draw in normal use.

Measure the current draw of the car with everything off.
 
Paint a line across the front of the harmonic balancer and see if it is slipping.

Sometimes, on a dirty motor, that's not half apart already, this is an iffy task. And then you have to drive it a ways to convince yourself the slipping is occurring.

Another method, with immediate results, is to check the timing mark against the zero on the timing cover. Just pull #1 plug, rotate the crank with a 15/16" socket until a soda straw or chopstick tells you the piston is at the top. If the pulley is slipping, and the mark lines up, buy a lottery ticket. :)
 
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