Bad Bendix?

[agesilaus]

OK here is the situation, my son has a 1998 Dodge 1500 p/u. It will not crank. It buzzes or sometimes clicks but does not turn the engine.

So far we've tested the battery with a DMM, it read 12.4 but he had almost run it flat. We went thru a series of checks I found online to test various cables and they all came out OK. He pulled the starter and took it to a parts store where it tested OK. Charged the battery up. Replaced the starter. It buzzes and that's it.

We swapped the two relays in the relay box, both could be bad I suppose.

We ran a jumper cable from the pos battery to the starter and it spins away but does not turn the engine.

All I can think of is a bad Bendix. Any thoughts? I had a bad one on my wife's Taurus years ago.

I told the kid to get online to the Dodge P/U forum but he isn't very good about asking for help. There are a hundred Dodge fanboys just waiting to answer nub questions I'm sure.

Thanks for any suggestions.

[agesilaus]

OK let me bring this thread to a finish. The kid replaced the starter---nope not that. Took that back. Took the battery down for load testing, nope battery is fine. Swapped relays, not that either. And finally bought an ignition switch, found it required some security bit to get it off and finally got it in today. It started right up...heh. And to top it off the kid at the beginning of all this said he thought it was the switch...heh. All us know it alls disabused him of that idea.

But on the other hand he got and education in cranking systems that he will use again over the years.

[eHoefler]

A shorted battery under load can produce the same result when on jumper and/or a charger. The battery will consume more power than the boosting device can produce.

[BenK]

yup...a mallet works most times...

My K5 had similar and fixed for a moment to get home via that mallet smack

If it has headers and/or exhaust manifold too close to the casting...it will over time degrade the solenoid so that it won't have enough flux field to pull the pinion into mesh with the ring gear

Fix for my K5 was a special coil spring (weaker) so that the weakened solenoid would still do the job. Had forgotten that, as it lasted for a long time after that fix

[rjstractor]

By connecting the starter directly to the battery you ruled out a bad ignition switch. A bad ballast resistor (if you have one) would have nothing to do with whether the starter physically turns the engine or not. Symptoms of a bad ballast resistor are the engine will crank and begin to start, but will die when you release the key.

As you determined, all signs point to a bad bendix. Sometimes a good hard smack on the side of the starter housing with a wrench will coax a few more starts out of it, but that's a roadside trick to get you home, not a fix.

[Grit_dog]

Typically a weak battery will not present as a free spinning starter that doesn't engage (sticky or bad Bendix)
That's why vehicles with even almost dead batteries still "try" to turn over the engine.
How could the parts store say it tests out fine even though the gear doesn't engage? Or did it engage on the bench test?
If it engaged on the test but not in the truck, then the more likely culprit is the flex plate is missing some teeth and the starter has nothing to catch. Bar the engine over a few degrees and try again to confirm or rule out that issue.
If it is the starter, no point in "repairing it" on a 20 year old truck. It's a cheap part that has pretty much lived it's life by now.

[theoldwizard1]

Check YouTube. Those Bendix can be cleaned and reused.

[agesilaus]

eHoefler wrote:
Have the battery tested, if it was allowed to go flat, or is over 3-5 years old, most likely it has a bad cell under load.

Using a jumper cable from my F350 produces the same results.

[eHoefler]

Have the battery tested, if it was allowed to go flat, or is over 3-5 years old, most likely it has a bad cell under load.

[sgip2000]

dockmasterdave wrote:
If the buzzing you are hearing is the starter turning in the bell housing, then yes, probably a bad bendix.
That is what kicks the gear on the front of the starter into the flywheel to crank the engine.
The resistor block on the firewall was back in the 60's I believe and was in place of the resistance wire all other manufacturers ran to the coil. It is there because after the motor starts, you don't want a full 12v to the coil. It will overheat and blow like a volcano. Ask me how I know this. LOL

Resisters were still used in the 90s. My 92 Jeep has one.

[wilber1]

dockmasterdave wrote:
If the buzzing you are hearing is the starter turning in the bell housing, then yes, probably a bad bendix.
That is what kicks the gear on the front of the starter into the flywheel to crank the engine.
The resistor block on the firewall was back in the 60's I believe and was in place of the resistance wire all other manufacturers ran to the coil. It is there because after the motor starts, you don't want a full 12v to the coil. It will overheat and blow like a volcano. Ask me how I know this. LOL

X2

The ballast resistor in old Mopars is in the ignition circuit.

[agesilaus]

Yeah we are zeroeing in on the bendix. My son went to the parts store and the guy there told him to short out the starter terminals. If it turned but didn't engage the engine then the starter was bad, period. This bypasses everything else, the switch and the relay. He did and as before the starter spins but does nothing. He'll get a new start Sunday.

[dockmasterdave]

If the buzzing you are hearing is the starter turning in the bell housing, then yes, probably a bad bendix.
That is what kicks the gear on the front of the starter into the flywheel to crank the engine.
The resistor block on the firewall was back in the 60's I believe and was in place of the resistance wire all other manufacturers ran to the coil. It is there because after the motor starts, you don't want a full 12v to the coil. It will overheat and blow like a volcano. Ask me how I know this. LOL

[agesilaus]

fj12ryder wrote:
Uh, the engine itself is free to turn isn't it?

Hmm hadn't thought of that. I has been running fine but cranking it was getting difficult over the las week. Someone local suggested a bad ignition switch so I guess we need to check that out.

[fj12ryder]

Uh, the engine itself is free to turn isn't it?