1988 Auto
For a few days now , when I turn the ignition key to start, the starter just clunks - it's hitting the gear on the flywheel but not turning motor over - after 2 or 3 trys eventually the motor turns over and it starts.

My battery was 3 years old and tested low, so I replaced it today- and still got the clunk- so I put the battery on charge for 4 hours -it started by drawing 1.9amps and at the end was drawing 1 amp.

I then tried to start the car and got 3 clunks in a row, then it jammed -obviously the gear on the starter jammed in the gear on flywheel.

I hit the starter with a pipe and then the car started.

When the starter does turn the motor, it turns it very well, sounds fine

Have I got a dud battery? - it was a good one, not a cheapo
Does the starter need some work?

I remember reading how the sliding part can jam because of heat which boils the grease away- I did a big search but couldn't find anything

S'nut

 

Sounds like a bad starter. Had one with the same symptoms, sometimes worked with a chunk sound, sometimes started perfectly for about two years till it finally quit starting altogether. Replaced the starter and has been fine since.

 

Before replacing the starter you need to do a voltage drop test. You can find the procedure in most any auto service manual and you need a digital voltmeter to do it right. DVM's can be had for about $20 now that are plenty good enough for DIY work. The small ones at Sears are good enough.

To do this you basically put the DVM in DC mode and connect the black lead to the connection at the starter MOTOR. This will be the connection from the solenoid to the starter MOTOR and will be a big nut. While an assistant is turning the ignition switch to the start position, put the red lead of your meter to the positive battery post, read the voltage and then remove the lead before the assistant turns off the key. Removing the lead first is to prevent damage to the meter. You should have no more than .5 Volts drop across this portion of the circuit. If you do, you can keep moving your positive lead back toward the battery to take measurements until your drop is below .5Volts. When you find the point where it drops below .5Volts the bad component is between where you had less than .5Volts and where you had more than .5Volts. This could be the solenoid or a cable.

The problem will probably turn out to be the starter solenoid, but given the nature of these starters if it comes down to replacing it, I would find a quality rebuilt starter and replace the whole unit.

I would not reccommend a starter from one of the discount parts chains like autozone. I would check out one of the suppliers here on the forum that sell genuine GM or Delco rebuilt parts.

Good luck and Merry Christmas,

 

Sounds like the solenoid is not making a good transfer of power to the starter motor. Poor connections may contribute to this. Also if the bendix is not functioning properly it mayl not allow the full connection of the contacts in solenoid.

 

Sounds like a starter or connection problem. I replaced mine 3 yrs ago with a Schucks-it has been working perfectly since-also a lifetime warranty-

 

Most likely the solenoid. I suggest rebuilding your starter if it is the original one, because many replacement starters require shims to get the correct bendix gear to ring gear clearance/gap. A good auto electrical shop can rebuild it for you or you may want to rebuild it yourself. You can buy the solenoid , bendix and starter brushes and bearings at most auto parts stores.

 

There are two parts of a starter that cause 95% of starter failures.( For those who require exact numbers I found 95% on the bottom of an empty mayo jar in the garage.) Those two parts are the solenoid contacts and the starter brushes. These carry the electrical load and fail soonest. Most parts houses will sell you a solenoid repair kit,thats just the contacts, and brushes,4 of them, for $10.00 or so. Caution,if your bendix gears are beat up get a new solenoid with a bendix.

 

Corvette starters do not have a Bendix gear in the starter motor. A Bendix gear moves forward on the starter motor shaft on the helix cut into the shaft when the starter motor accelerates and this forces the gear into engagement with the flywheel ring gear to turn the engine for starting. Corvette starters use a solenoid that pulls the spur gear on the starter motor shaft into engagement with the flywheel ring gear. The solenoid also at the end of its stroke forces two copper contacts together to supply current to the starter motor. These copper contacts get pitted during normal use and eventually will not carry the 100+ amps a starter motor requires to crank the engine. The contacts are replaceable. You can test your battery by measuring its terminal voltage during cranking. It should not fall below 9.0 volts or the battery is discharged, cable connections are not clean and tight, or the battery is at the end of its life. In your situation with a new battery that is charged up, most likely the contacts in the starter need replacement. You can buy the parts and replace them yourself or you can take your starter to an auto electrical shop for repair.

 

Thanks jfb and everyone, will do tests-most probably is the contacts - I'm in Australia, so unfortunately can't just pop down to the store for a repair kit, but I expect an auto electrician will be able to R/R the solenoid.(once they recover from Xmas)

Next question is - how easy is it to take the starter off the car?

S'nut

 

Well, I was afraid you were going to ask that. Just like 90% of everything else under a Vette hood , It's a PITA. Problem is that good ole GM routed all the hard tubing lines right beside the starter. Best way I found to deal with it is to get some heavy duty Tiewraps and tie all the tubes off to the Exhaust pipe (cold ) so that you can then get proper working room . BTW, please disconnect the negative bat cable before you start!! I found that you can access the starter wires better if you take the mounting bolts off the starter so that it can be dropped down . Then you can remove the nuts for the wires and remove them. You will need to wiggle the starter around some , but it should come out. Mine is an 86 , but I think most years of that vintage are similar. If you have a helper, to hold up the starter while you unbolt the wires and replace them on the new starter, it's a plus. I ended up with a bad elbow from trying to hold up that darn starter !!. Not terrible complicated job , just a PITA.

 

Thanks dwestsr, if changing a battery means dismantling a side panel, then I'm not surprised removing the starter will be a pain!!

Very little info in the GM manual except for 'remove flywheel cover' - and nothing about the flywheel cover in the Helms which has more info.

Thanks for tip about undoing leads -

Anyone got pics of the solenoid internals, the contacts etc - or any info on cleaning them up? I may have to do a temporary clean of them, to get through the holiday period, as my vette is my daily driver - then get it fixed properly in January.

S'nut

 

If I remember correctly-the contacts referred to as getting pitted etc. kinda looks like a copper washer located right behind where the positive cable attaches to the solenoid-and it seems to me in leaner times we loosend the bolt to it and rotated the copper washer-plus cleaned the rest of the solenoid and starter. Just pay attention to any shims when you pull the starter.

 

solenoid repair - any pics or info would be very appreciated - I'm having a bad run with my daily driver vette at the moment - but I refuse to give in

thanks

S'nut

 

Just posted and edited above your last post-hope it helps.

 

hey i just detailed my car and took off a nice thick coating of dust and dirt and carbon off and my starter started working again.
I think Sarah was pi$$ed i hadnt washed her for two months.
i still get a clink as she starts but she gave me some time till i have to replace the starter

 

You are on borrowed time. If your problem is the soleniod contacts, then consider your self warned . Do not be surprized to find yourself in the middle of nowhere and Sarah wont start. Usually , once the solenoid fails to make contact a few times things rapidly go downhill . Good luck!

 

Don't know of an easy source for solenoid parts - '88 uses the Nippondenso starter; I have no idea who made the Solenoid - Dealer remans are under the AC Delco label. NAPA lists the brushes and drive, but the solenoid is a complete unit (though I don't remember it being terribly expensive). I do think it's better to replace the whole thing - proximity to the side of the Y and the precat seems to play havoc with the windings. You would hope that the Nippo brand would speak to quality, but I have feeling (and having had to replace my own), that the bean counters simply saw a favorable exchange rate and switched manufacturers.

 

Thanks Bill, Rick etc all the workshops are closed now till Jan 2nd or 3rd - Won't know if replacement is available here in Aus until I take starter to repair shop.

I'm tempted to try the rotating washers just to get me through the next week - but it's a lot of work.... so I've talked myself out of it for the moment.

S'nut

 

If the starter is original I would replace it and be done.

 

I'd just buy a rebuilt and be done with it-I maybe fortunate, but throughout the years I'v never had a problem with rebuilts.And quite honestly trying to clean up the starter and solenoid are not a
sure fix-I've had luck-and failure, those were in lean times with kids to feed, now I don't have time or inclination to mess with starters, checking relays or other relatively inexpensive parts. If it were my only transportation and I couldn't afford to replace it I'd certainly go thru it again.But like I said-trying to clean up and repair especially the solenoid is a hit and miss proposition.Good Luck and let us know!