It's gotta be the starter...doesn't it?

[gw84]

On my last truck I knew the starter was going bad when it took longer and longer to start before it finally wouldn't start until I tapped on the starter, ultimately wouldn't start at all..

With this k1500, I never had the slow starts, it just wouldn't start one day. Tap of the starter and it finally started. Ran fine for a couple days, then again wouldn't start. Tap on starter, fired right up.

It's just odd that my 2 experiences were so different. Which one is more typical?

[brcidd]

With any DC motor, if tapping on it makes it go - it needs replaced- brushes are out of alignment to armature- due to wear. This applies to fuel pumps, wiper motors, window motors, starters, blower motors etc...Tapping on it centers brushes temporarily.....and is in itself a diagnostic tool to prove what is wrong and what needs replaced....used it for years- have started many a truck for others by beating on their gas tank- then told them to drive to the service center to replace their fuel pump.

[gw84]

awesome, thank YOU!!

[j cAT]

Originally Posted by gw84

awesome, thank YOU!!

the starter does have brushes so tapping it may get it to work. I have found that the solenoid contacts do not last as long as the brushes in today's engines. since these engines have high voltage ignition systems. also a PCM that creates the perfect fuel mixture on any start this results in much less crank time so the brushes very rarely wear out before the solenoid fails or even the starter motor bushings.. The last time I ever seen brushes worn down was on a GM with distributor points and a carb. 30 plus years ago.

[ASJT3]

Originally Posted by j cAT

the starter does have brushes so tapping it may get it to work. I have found that the solenoid contacts do not last as long as the brushes in today's engines. since these engines have high voltage ignition systems. also a PCM that creates the perfect fuel mixture on any start this results in much less crank time so the brushes very rarely wear out before the solenoid fails or even the starter motor bushings.. The last time I ever seen brushes worn down was on a GM with distributor points and a carb. 30 plus years ago.

I would agree with j_cat, corrosion is typical on these contacts and results in progressively poorer starting, although I have also seen it just abruptly stop working. Use a lot of dielectric grease on the new contacts