1987 Chevy Corvette V8 Two Wheel Drive Automatic 125000 miles
I have a 87 C4 Corvette I got in a trade deal a few years ago, and it has been sitting in my garage ever since (I took it on trade because my son-in-law wanted, by my daughter got pregnant, need I say more). Anyway, a couple months ago I started tinkering with it, and to date I have drained the fuel tank, replaced the fuel pump, installed a new fuel filter, replaced all the O-rings on the injector rails, put in an ignition module, replaced the plugs, wires, cap, rotor, and battery, and while I was flushing the cooling system, I noticed that when it got hot, it wouldn’ t start (which I understand is a common problem Vette’ s, due to the starter getting hot), but if I would let sit for 10 or 15 minutes, it would start again.
Then, the intervals between the starting problem occurring, lessened, to the point where it just wouldn’ t start, and since starters are a common problem with Vette’ s (or so I am told), I purchased a starter, and when I started to install it, I noticed that the starter in the care didn’ t appear to be that old, in fact, it looked in relatively good condition (like it had been replaced not too long ago).
Anyway, I replaced the starter, and before reassembling everything, I tired to start the car, and nothing, so I took the wires off the starter, and cleaned the ends with sandpaper (to make sure good contact was being made), and when I reconnected the wires, it started right up, and I started it several more times, and it started every time, so I put everything back together, and when I attempted to start it again, nothing, it wouldn’ t even turn over, it was as if the battery were dead (but it wasn’ t, I checked, and it was 95% charged).
So know I’ m back to square one, and since I really can’ t find an external (to the starter) relay, or a fusible link, or anything else in the starter circuit that might be the problem, I’ m at a lose?
One final comment, I just went out in the garage and the damn thing just started right up, and I stared it a half a dozen times, and it started every time, so now I am going to go out and try to start it one more time before I send this message, and see what happens?
Yup, it started again, but since I have no confidence that it will keep starting, does anyone have any suggestion(s) regarding what I might check next?
The starter grounds to block, so check the ground. Use a multimeter (set on low ohms) and touch starter case and block during one of these no start events, if you get no reading, then the ground is problem.
Then clean battery ground to block and contact surface.
See if that solves problem.
Another possibility is the ign. Switch.
Any aftermarket/factory security systems on the 'vette?
February, 27, 2009 AT 2:45 PM
There is no aftermarket/factory security systems on the car, but I did notice something interesting this morning after starting the car. Yes, the car started this morning, but only after charging the battery, with the ground side of the battery disconnected, read on!
I put a charger on the battery last night, and the meter showed the battery to be at 80% charge, and it was still at 80% charge when I checked it this morning. So I disconnected the ground side of the batter, installed a lug, and charged the battery with just the positive cable connected to the battery, and the battery charged to 100% in about 30 minutes.
I then connected the ground lead to the battery, and the car started on the first try (and several times in a row), then I put the charger back on the battery, and it was at 95% charge, and since the battery wouldn’ t accept a charge (just maintained an 80% charge over night, while on the charger), could we be looking at corroded ground wire, or maybe a short somewhere?
The battery that was in the car was a few years old, so I just assumed that a new battery was needed, but since the new battery is loosing charge after only a few starts (and won’ t accept a charge with both ground and positive leads connected to the battery), could there be a relay, or some other component in the circuit that’ s faulty… and the plot thickens!
February, 28, 2009 AT 8:40 AM
I would check all grounds, check the resistance in each one if necessary.
Put the multimeter on the battery at its most sensitive setting (battery in car, connected) in DC volt mode. See if you are getting a drain, which would be considered a constant 1-2 amps. If battery is going below 12 volts overnight, recharge and remove battery from car and repeat test, if battery holds 12V overnight, then there is a drain in the car somewhere. And these can be hard to isolate.
Best way to isolate a drain is get an " amp clamp", hook up to negative battery cable (battery in car connected). Observe drain and remove fuses one at a time until you isolate drain circuit.
February, 28, 2009 AT 10:58 AM
I think we're headed in the right direction, this morning I cleaned the small/secondary ground lead from the battery (that was corroded), and the positive side junction block located behind the battery, connected the charger, and it charged to 100% in a matter of minutes (when before, it wouldn't accept a charge).
However, after starting the car several times in a row, on about that sixth try, I turned the key, and nothing, just like before, and when I checked the battery, it was @ 95% charge, and since the battery is only a few days old, I'm assuming it's not the battery (but I'll check).
That said, I've had the car in storage since I acquired it a couple years ago, and it's never been hard staring until recently, so maybe it's just corrosion that's built up over time?
Anyway, I'll proceed as you suggested, and stop replacing parts until I find the source of the problem (although the new battery and starter were probably not a bad investment in a car this old).
February, 28, 2009 AT 6:44 PM
As you suggested, during a "non-start" event, I took a reading on the block and starter housing, and it didn't appear to be grounded, and the end of the ground thermal attached to the block was really corroded (there were 5 connectors attached to the ground bolt), so I took a reading across the connecters, and nothing, so I took it all apart, cleaned it, put it back together, and it started right up (10 times in a row).
So I put everything back together, took it down off the jack stands I had it up on, got in to back it out of the garage, and when I went to start it, nothing, nodda, zip!
So explain to me what you mean by an "amp clamp" , I've never used on before? "Oh" and the battery as been holding at 12.79 volts all day!
February, 28, 2009 AT 10:44 PM
A battery can read 12.5 volts but only have 200-300 amps to start, which generally is not enough.
Batteries are rated at CCA (Cold Cranking Amps) both at 0 degrees F and at 32 degrees F.
Battery testers will measure voltage and rated amps, although the battery will check out at 12.5 (or whatever volts) it is the amperage that starts it.
An " amp clamp" is simply a tester that connects to the negative cable and reads any drains on the battery, I suggested it as a way to test any parasitic drains on battery.
Most auto parts stores have the amp clamps and they can measure drains on battery.
I would have the battery tested, for any drains on battery, although I think you have a ground problem, a intermittent loss of grounding.
You may be better off running an additional ground wire from battery to block.
And again, it could be a faulty ign. Switch.
March, 1, 2009 AT 10:27 AM
Thanks, and I will run to Autozone and pickup an amp clamp!
BTW, the car started this monring, no problem, and I re-started it a couple times, no problem!
Then I turned it off, moved a few items so I could back it out of the garage, got back in the car, and it wouldn't start, nothing, all the dash lights came on, everyting else works, but when I turn the ign to start the car, nothing. I let is sit for 5 minutes, and it starts right up!
Don't know if this tells you anytying, but that's what's happening. Frustrating!
March, 2, 2009 AT 6:50 AM
Get some 6-8 gauge wire and run a ground from starter housing directly to block. See if there is a bolt on starter housing you can use, and run to clean bolt on block.
March, 5, 2009 AT 6:37 AM
Thanks, I'll give that a try!
Update on troubleshooting: the batt seems to be holding the more gound cleaning I do, and in two days volts has dropped from 12.79 to 12.33.
Also, I went to several auto parts stores (Autozone, NAPA, etc.), And asked for an " Amp Clamp", and was looked at like I was from Mars, no one ever heard of an amp clamp? So, I got a couple small clips, and was thinking about just hooking my meter up to the batt and using it to measure the drain, will this work, or am I way off base on this?
March, 22, 2009 AT 4:23 AM
If I had to guess, I would say an AMP clamp would go inline on maybe the positive battery terminal and would " clamp" any parasitic drain to the battery while the car is parked to limit the maximum allowable amperage drain to save the battery from going completely dead overnight.