Case 580 B?? Starter Grinding Ring Gear

[Cessna49]

Hello,
I just purchased a Case 580, was advertised as a B model but I think its an early model 580 with a model 33 backhoe. The seller told me the starter was replaced/rebuilt a few years ago, he couldn't remember If the actual owner (who has since passed away) had the old one rebuilt or bought a new one. When you hit the start switch the starter will turn the engine over for just a second and then just grind on the ring gear. Can anyone help me out here, it looks like the starter is not engaging all the way... Is the Bendix on the starter incorrect for the ring gear? I know I will be replacing the ring gear/torque converter most likely but need to get this guy started at least once to get it on the trailer. Any and all help/advice will be much appreciated.

 

[Tinkerer]

First you need to determine if that is the correct starter. Hopefully it is a Delco0Remy and not a noname aftermarket one. The DR will have the part number stamped on a tag on the frame of it. That # is how to determine if the starter is the correct one.
The real problem is the ring gear. It appears that is your problem with bendix kicking out of engagement.

 

[edgephoto]

Make sure you have a good connection. You should voltage drop the power and ground side of the starter circuit. If you are not sure how to do a voltage drop or what it is measuring just ask.

Have you inspected the ring gear? If a starter is not fully engaging the ring gear it will grind away teeth. Then when you fix the starter and it hits that area you end up with problems. It could also be a solenoid issue. This is why measuring the voltage drop is helpful.

 

[Cessna49]

Tinkerer:
Thank you for the reply, I will check this morning to see what info that starter has. Do you happen to have the part# for starter? Also can you tell what model this backhoe is? I know it says 580B on it but I think its a 580CK, I didn't get the serial number off it.

Edgephoto:
Thank yhou for your reply as well, I do not know how to do a voltage drop or what that means?? The ring gear is chewed up some, if you check out the photo you can see the tips are messed up. I know I will be replacing that... I need to be able to get this thing started to load it and before I put a bunch of time and money into it I want to make sure its worth it. It seems to me that the starter teeth should be grabbing much more of the ring gear teeth. I could be wrong but it just seems that there is plenty of tooth left on that ring gear to turn the engine over to get it started one time. But, I also need to understand why the ring gear is being chewed up to begin with.

Thank you for any and all input.

 

[Tinkerer]

A weak bendix drive and time will make a ring gear look like yours.
It is impossible to determine if the correct starter is on it without knowing exactly what model machine you have.
Case used several different starters on the 580CK and 580B. See below is an example from the 580B parts book
The Case part numbers can be cross referenced to Delco Remy numbers on the internet.
There is a chance the starter you have is not fully engaging the ring gear.
With the starter off the machine hook it up to a battery and spin the starter . Look for the bendix gear to completely go to the washer that is on the armature shaft.
You can measure the distance from back side of the ring gear teeth to the starter mount.
Next measure the distance from the starter mounting flange to the bendix gear when it is fully extended.
That should give you a good idea if the starter is fully engaging the ring gear.



.

 

[Cessna49]

Hmmmm, well I guess I need to get the serial number off the machine. I am going to take the starter in and get it tested to make sure it is functioning properly.

 

[edgephoto]

A voltage drop is measuring the resistance in the circuit. You perform the measurement while the circuit is activated. In high current circuits such as a starter a very small resistance can cause a large loss of voltage. You would not be able to really measure the resistance in Ohms.
Ohms law is: Voltage = Current X Resistance.

For example in a starting circuit you may draw 500+ amps. If we lose more than .5 volts we have an issue. Let's say you measure 2 volt when testing. The formula becomes 2 volts/500amps= .004 ohms. You are not going to measure .004 ohms with a meter. This is why voltage drop testing is used.

To measure everything in the circuit make sure to connect to the actual battery post. This way if there is resistance in the battery terminal you will measure it. The ground is provided by the chassis so just use the starter housing for one connection. It does not matter which way you have the + and - leads. The number measurement is what you are after. You should measure under .5 volts. Anything above that is an issue.

Also measure the battery voltage when cranking. If it drops below 10 volts you need to charge the batteries or replace them. The solenoid won't hold if the voltage goes low.

Best to diagnose your problem vs. changing parts.

The picture shows how to hook up the meter. You do the test on the ground side and then the power side. If either is above .5 volts you know which half has the issue. Then we can do more tests to determine exactly what is the issue.

 

[Cessna49]

wow ok I can do this test, can I do it with the starter removed? I ask because when it is installed the starter just grinds on the ring gear and don't want to cause more damage then already done. I really appreciate the help!

 

[Cessna49]

The starter is a DelcoRemy with the numbers 1998442-3J29 stamped in the side of it.

 

[edgephoto]

wow ok I can do this test, can I do it with the starter removed? I ask because when it is installed the starter just grinds on the ring gear and don't want to cause more damage then already done. I really appreciate the help!

Well sort of. You won't really be testing the ground side properly. You don't have to run the starter for long just a quick crank. The damage is already done.

 

[Cessna49]

I took the starter into the starter shop to have it tested, everything tested out good.

 

[edgephoto]

Then I would do the voltage drop test with the starter installed. If the voltage is not correct then your solenoid may not hold.

Most likely the ring gear was damaged from the starter prior to repair.

 

[Cessna49]

Thank you, I will try this when I make it back out to the backhoe. It will be a few days unfortunately.

 

[Tinkerer]

To further complicate things, the 188 diesel uses two different bendix drives. A 9 tooth and a 10 tooth.
That is why the serial number of the tractor is so important to have. Otherwise you have to count the number of teeth on the ring gear and figure which bendix drive it uses.
Either drive will turn the engine but bad things happen if the wrong number of teeth are used in it.

 

[edgephoto]

I would make sure you have the right Bendix on your starter.If it was rebuilt it is very possible you have the wrong one installed.

 

[Cessna49]

I will work on getting that serial number today, Im not sure how to look that up once I get it. I will post it here and hopefully can get some guidance on what I have, or should have anyways.

 

[Cessna49]

It appears I have a 10 tooth Bendix on my starter now, just the best I can tell from the picture. I will count that though.

 

[Tinkerer]

It is most likely the correct one.
The tractor serial number will determine if it is.
Unless the motor has been replaced. Counting how many teeth that are on the ring gear is the absolute way to determine which bendix gear it requires.
With a good ring gear the sound of the starting motor turning will let you know immediately if the right gear is turning it. Been there done that.

 

[Cessna49]

I confirmed I do have the 9 tooth Bendix, waiting on a picture of the serial number....

 

[Delmer]

Your starter doesn't look that bad compared to the shape of the ring gear teeth. I would have liked to see the old starter to see how it could get that bad.

Even with the shape of the ring gear, it should stay engaged fine with the amount of teeth that are left, it doesn't seem like it's engaging anywhere close to far enough, or it's falling out repeatedly, or something along those lines.

The way those teeth are "smeared" makes it harder for the starter teeth to engage, you can correct them with a file and a lot of patience, so that the teeth ends are the same profile as the surface of the teeth, and the back edge of the tooth has a little relief like the teeth on the starter gear, but that usually makes a starter fail to engage and spin, not kick out after it's engaged.