Screaming Starter: Bad Bendix?

[ratdude747]

Been getting some weird noises from the starter yesterday and today.

Sounds like it's running way too fast... like an electric drill. The engine does crank over and start.

That's a sticking bendix, right? Time for a new starter?

[ArdWrknTrk]

I'm not sure why a bad bendix would cause a starter to turn the engine over faster.

I've just ordered a few replacement starter drives and nosecone bearings because my collection of shredded starters has reached five,  not including the one in my truck.

If going replacement you might consider a PMGR, from a mid '90's truck.
They eliminate a lot of the load on the fender relay and only require a single 12Ga. wire run down alongside the starter cable.

[ArdWrknTrk]

A sticking Bendix doesn't want to retract, so when the engine starts it drives the starter like a generator until the pinion gear finally comes back in.

PMGR's use the solenoid on the side to force the pinion gear out, and to retract it.
You can't get in that situation with one of them.

[ratdude747]

I know, my 1995 Ranger (and the one before it) has a PMGR starter. I've had solenoid issues with some of those in the past (the ranger before it, the day before my wife wrecked it), so at least to me, the swap is moving the problem from something I can easily access (fender relay) to something that's covered in dirt and under the truck. My F150 already had an aftermarket upgraded starter relay installed when I bought it, so at least for now, I'm electing not fixing what isn't broke (if I replace the starter, sticking with the stock style).

Haven't gotten the noise since this morning's cold start (twice last night, and once this morning). Started no problem, but it sounded like a corded black & decker drill at full speed.

If it's not a bendix sticking closed, then what is it? Rather not throw a starter at it without a good reason.

[ArdWrknTrk]

The usual problem with Ford's implementation is that they used a spade connector, that always got corroded.
Put a ring terminal on the trigger and put that directly to the stud.


Just how cold is "cold"?
Lots of worn out starters drag when hot, because the armature is rubbing on the bottom of the stator.

The same thing can happen cold.
The bushings are a little worn out and the sloppy armature is rubbing because the case has contracted overnight.

[kramttocs]

Don't want to interrupt your troubleshooting but had a couple questions.

1. Screaming only means spinning fast, correct? Not screeching, grinding, clunking, etc? So the only noise is what sounds like it's spinning faster than normal?
2. Does the engine itself crank over faster? May have to disable ignition to get a good feel for the speed.

Essentially does it sound like it's just spinning faster or is it really spinning faster?

Either way it's probably worth pulling it, giving it a visual inspection, and getting it tested.

[ratdude747]

Fast spinning. Like an electric drill. Based on how quickly it starts in this condition, it does seem to be turning faster. Not a consistent issue... Sometimes it cranks normally. If it matters, I replaced the flexplate this spring when I rebuilt the motor due to chewed up ring gear teeth.

I'd pull it to inspect if my other truck wasn't out if commission.

[kramttocs]

Sounds like the solution is a third truck

Truck runs fine once running? Power feels normal?

Never heard it cause the starter spin faster and it's just throwing parts at it, but swapping out the fender mounted relay is an option that doesn't leave the truck down.

[ArdWrknTrk]

The only thing I ever hear from a corded electric drill are the brushes on the commutator and the gears in the reduction housing.

And if you have a new ring gear it shouldn't be bad engagement.  

I'm just not understanding how it could be turning fast.  

[kramttocs]

At least not randomly and if the truck is still running fine (has compression).

My powermaster starter overruns but that's just because it's overpowered for my compression.

[ArdWrknTrk]

Scott, I'm not really understanding what you mean by "overruns"

My understanding of overrun is when the starter is being driven by the engine.

And even if you had a 10hp starter the pinion gear would retract as soon as power stopped being driven through the reverse helix in the bendix.

[kramttocs]

Overruns isn't the right term then. We'd discussed it here awhile back as I was concerned but from what I recall it was just decided that due to the gearing of the starter it just makes more of a whirring noise.

I don't want to derail from ratdude's truck though - I only mentioned it because my understanding was that it is making that noise because it was made for higher compression engines and that was going back to compression being the only reason I could think of for a starter to run faster, all else unchanged.

[ArdWrknTrk]

I don't want to derail his thread either.

But he has a moveable pole type starter, and im trying to get a handle on why:

It would spin faster
Sound like it was crappy mesh, with a new ring gear.

I agree with you. If there was no compression it would turn over quickly.


Didn't realize (remember) your starter was gear reduction, Scott

[kramttocs]

Sorry - I meant that I had derailed it with an apples to orange comparison.

I just remembered that I had taken recordings  so maybe if ratdude could do that also to try and capture both a normal and fast start it might spark some ideas?

[ratdude747]

Yeah, I'll wipe out my bonus on another truck... I wish. If anything, I need to replace my wife's 2002 Escape that's a pile of rust and a puddle of leaked tranny fluid. But anyway...

---

Engine runs as well as always. Starts easily (as long as the choke is set when cold, obviously), gets the same "crappy" 12-13MPG it has been getting (and I've learned to live with, it's not rolling coal so I really dunno).

[ArdWrknTrk]

Is there a chance you could record the starter first thing on a cold morning?

Like Scott said, it might help us figure out what's wrong with it.