starter solenoid engages, but no crank

I've read through the FSM, Haynes, and Chiltons, and am still ignorant about this.

If I turn the key to start position, I hear a big clunk, but the engine does not crank. It seems that the relay is good and the solenoid is engaging (the clunk), but the starter motor does not appear to be turning. I hit it with a hammer a few times and it did not help matters.

Is there a way to jump this or do further testing while the starter is still installed? I need to move the vehicle since it's blocking my dad's truck.

Thanks

#1 Do not hit a starter with a hammer. You man crack the ceramic insulation inside.
#2 Automatic or standard?
If Auto try to rock it front & back WHILE IN PARK.
This may realine the flywheel and or realign the starter armature & get it off a dead spot.
A solenoid clicks, a starter bendix will spin & wine.
If standard, try to push start it.
Either way make sure you have good electrical contact at all points.
Be safe no matter what you do.

you have a main battery terminal or connection bad.
or less frequently, the starter or battery itself.
if your lights dim greatly also when you try to start it, that's (connections) where to start.
If it won't start by jumping the battery directly,at the post terminals, it's likely a connection after the battery.

A little more info...

Battery reads 12.6v at the posts, and I get the same reading on the solenoid power post and a nearby ground. When I read the ignition post on the solenoid (the small one) while a helper turns the key to the start position I get about 10.5v which is lower than normal but more than enough.

If I use a jumper cable from the battery post to the post on the starter motor (bypassing the solenoid altogether) then the starter motor will spin although the engine does not really crank (it does a little bit but mostly the motor just spins).

Using a screwdriver to jumper the solenoid power post and the output post to the starter motor, all I get is a load of sparks and no activity.

Any ideas appreciated.

It probably doesn't crank right when you jump it because it requires a very good, tight connection for that circuit. But you have eliminated a ground I would think. Not sure of your year but with Renix, I would go to the thing (help me guys) with all the fuse links attached just rear of the battery.

Bad solenoid.

The motor needs to spin and the gear needs to be thrown out torwards the teeth.

Edit: If you care to, the fusible links are right near the Starter Relay behind the battery. It's where the positive cable branches off to before going to the starter.

ehall said:

A little more info...
If I use a jumper cable from the battery post to the post on the starter motor (bypassing the solenoid altogether) then the starter motor will spin although the engine does not really crank (it does a little bit but mostly the motor just spins).

Using a screwdriver to jumper the solenoid power post and the output post to the starter motor, all I get is a load of sparks and no activity.

Any ideas appreciated.

Click to expand...

Either your engine ground is bad or the starter's toast. You eliminated everything else with this test.

89CherokeePioneer said:

Bad solenoid.

The motor needs to spin and the gear needs to be thrown out torwards the teeth.

Click to expand...

I hear a clunk when I turn the key so I think I am getting the engagement, but the starter motor does not spin.

However when I apply power directly to the starter motor then the motor spins up, but obviously the solenoid is bypassed so it is not engaging the rod.

So it seems that the solenoid is doing it's mechanical thing, and the starter motor is working when it gets power, so the solenoid is not passing power to the starter motor. so... bad relay inside the solenoid itself?

BTW this is 91 4.0 HO w/ AW4

mine had a similar problem but without the "clunk" !! i took out the starter and had it cleaned. Try to hit it with a hammer while someone tries to crank it! do this at the same time and it may work! it did for me

nick

Put a voltmeter on the lower large solenoid post (electrical output to the starter,) turn the key, and note the reading. You should get zero voltage with the key in any position other than START, and you should get battery voltage in START (if you get a reading there all the time, you need to be on the other large post!)

The solenoid does two things for the starter motor: 1) it extends the pinion gear so the teeth will mesh with the ring gear to turn the engine. It does this by pulling in a plunger, which 2) closes contacts in the solenoid to allow electricity to flow through the motor windings to turn the starter motor.

If the solenoid contacts are burned out, you will not get electricity to the motor windings - which means that you won't turn the starter motor. This has nothing to do with the starter motor relay or fusible links/fuses, since they're inline to the solenoid circuit from the ignition key (ditto the NSS. If you're hearing a "clunk" when you turn the key to the START position, they should be fine - that "clunk" is the pinion gear extending.)

My money is on the starter solenoid failing, and the contacts are burned out. It do happen. A quick check is to dismount the starter motor, grab your booster cables, and wire the positive lead to the starter solenoid screwpost (the large one) and the negative lead to one of the mounting ears. Put your foot on the thing, and jump the small post to the larger one - you should see the pinion extend and then turn. If you see it extend but not turn, the contacts in the solenoid are shot - replace the solenoid or replace the starter motor entirely.

i once had a chevy van that the alternator had locked up on and it did the same thing cut the belt off and voila it started try to turn the engine by hand

My '00 had a similar problem, but it was intermittent. The brushes in the starter were worn out. I fixed it temporarily by disassembling the starter and cleaning the brushes and contacte. New brushes are not available and I had to replace it.

Mine did the same while out wheelin last weekend, I rapped it with a hammer to get it started to get home, and just put a new one in. was under warranty. I think mud and water fouled mine. Was out muddin with my brother , his packed it in to, both within a week of each other

I put on my dirty clothes so I could pull the starter, figured I would give it a crank to see if anything new happened, and she started right up.

Must be a weak solenoid. I'll replace it next week.