'99 Yukon won't start

[mtwhite]

Just bought a 99 Yukon with 43K mi. Since the first week the car will intermittently not start. It clicks 1 time when the key is turned. There is plenty of lights/radio/heater, although those are turned off during the attempt. It has a brand new battery. I have been told this may be a problem with the shims on the starter, that it doesn't line up with the flywheel. Any thoughts?

Thanks in advance.

Mark

[herefordman]

If it only clicks the one time I would be looking for a bad connection somewhere, or possibly a dud new battery, otherwise its the starter solenoid, I'm not sure, but don't think the starter even has shims in it anyways, which engine is it ?

[mtwhite]

It's the 5.7L V8 Vortec engine. I thought the battery at first also, but it won't start even if jumped. I read on the web that if it was the starter/flywheel that putting the vehicle in gear and rocking it would engae the flywheel. Still wouldn't start...but I'm sure the neighbors got a kick out of watching. You could be on to something with the bad connection thing, where would I start to look?

Thanks again for your advice.

[GMMerlin]

Well there are a couple things you can do to find out what is going on(without becoming a source or entertainment for your nieghbors)
First, check the positive battery cables for signs of corrosion...if they are, clean them with a baking soda and water solution.
Next, if you have a test light, you can check the control portion of the starter circuit to see if it is powering the solenoid to engage...have someone turn the key to the start position while you check for power at the small purple wire to the solenoid..

The way the starting system works is when you turn the key to the start position, power goes from the switch, through the CRANK fuse to the park/neutral switch on the trans, through the start relay coil...this then energizes the start relay and it sends power to the solenoid.

[mtwhite]

Ok, everyone should love this. I twisted the battery cable 1/4 inch clockwise and the bleeping thing started. The bolt is tight but the cable will spin if you twist firmly. I tightened the bolt 1/4 turn and it doesn't start. Eased it off, and it starts. The cables are very clean, no corrosion of any kind, with battery grease between the cable and posts. What can I say...I'm really not this dense. I solve PC/software problems for a living. (...no pocket protector.., maybe that's the problem...)

Sincere thanks to both of you for your thoughts, I'm convinced this message board is better because of your involvement.

[herefordman]

Don't feel bad, everyone who has ever owned a vehicle has overlooked something they never would have believed they could possibly miss, at least you kept the neighbors happy for a while !!
Merry Christmas