Bad starter?

So I've been having a weird problem lately with my 1993 xj600. Here's the details in a nutshell. When I start the bike the positive post on the battery gets really hot. If it's a cold day and the bike hasn't been started for a while I need crank it for a bit then it kills the battery quick. Seems like the starter is draining the batt. It's a brand new battery and once I charge it back up is fine. Batt load test and charging system both good also so all good there. I checked the cables to see if they were grounding or shorting any place but found nothing. I was told it could be high resistance in the starter causing the draw issue. Now I rebuilt this starter about a year ago. Brushes, seals, etc but I'm still convinced it's something with the starter causing it but I'm not sure how to test it. Maybe bad windings or something? Anyone know how I could test it with a multimeter? That's all I have.

 

[QUOTE="PepNYC, post: When I start the bike the positive post on the battery gets really hot. .[/QUOTE]

That's a clue right there. Heat = resistance or loose connection. There must be a bad connection right there. Either a loose bolt or corroded terminal on the cable. Clean and tighten the battery cable first, check all the other cable connections to the starter while you are in there. Be sure to also check the battery grounding cables too.
Try that and see what happens

 

You can also add that the heat and resistance from a poor connection will make the battery appear bad because as the connection heats it drops excessive voltage. You can actually troubleshoot this with a DVM by performing a load test while the bike is cranking. If the issue is caused by a poor connection a meter lead placed on the battery terminal (not the cable) will show a healthy battery voltage. If there is a poor connection the DMM placed on the battery connecting cable will show a significant drop in voltage. You can take that a step further and place the DMM probe on the battery positive at the solenoid just in case there is a problem with the high current wire or crimp.

 

I checked all the connections. Positive from the battery to the solenoid. Neg to the engine block. Black solenoid cable to starter. All are clean and tight.

Rooster, What's a DVM and a DMM. Digital Voltmeter and multi meter? Can you walk me through that once again?

Oh, one more question. Does this look right? I'm not understanding why all the washers. There's 3 cardboard red ones on the bottom, then a metal one then a nut then the cable then another nut.

 

Those are insulators to keep the positive post from contacting the starter case (which is how the motor is grounded).
The lower nut holds the post in place. The upper nut holds the cable in place.

This thread will let you see how it all works.
Replacing your starter motor brushes w/ pics

Your washer stack looks like it's installed incorrectly. There should just be one or two red fiber washers on the case, and then the lower nut. I wonder if the post is contacting the case inside of the hole.

 

1. Connect the DMM negative lead to the battery negative terminal
2. Place the DMM positive lead on the battery positive terminal (not the cable) and crank the bike - note the voltage
2. Place the DMM positive lead on the attached battery terminal and crank the bike - note the voltage
3. Extra check or just do this instead of step 2 - connect the DMM positive lead to the solenoid wire that connects to the battery positive and crank the bike - note the voltage

With good clean connections the voltage should be the same. If you have a poor connection the voltage at the battery terminal (not the cable) will be considerably higher. With a good battery / starter combination the battery voltage should be 10 volts or greater when the bike is cranking.

If the voltage is dropping to less than 10 volts and the battery is good some thoughts:

The starter could have shorted segments causing excessive current. I am not an expert on starters but I believe commutator segments can short if they are not properly undercut or cleaned
The starter segments on the commutator should be checked to ground at each segment - none of the segments should go to ground. If they do the starter would need to be replaced or rebuilt - Yamaha specs the segment resistance but it is so low (.014 ohms) that it can't be measured with a standard DMM.
Anything mechanically that would cause the starter to turn too slowly - the starter motor will produce a back EMF field as it spins, the faster it spins the stronger the back EMF field and consequently the lower the current

I looked at a couple of kits on Ebay and some seem to have all those washers. It does not really matter as long as the starter post is insulated from the starter case and a good mechanical connection can be obtained between the starter post and the starter cable.

And maybe post a pic of your positive cable battery to solenoid - it's not undersized by chance?

 

I saw that post. Good information. Different starter though but basically the same principal. I took the starter apart yesterday to check everything. All looked good. I don't think one extra red fiber washer would make a difference though would it? The black insulation on the bottom of the post inside the starter case looked ok.

 

Did what you said. Hovered around 11v each time.

Here's some pics of the solenoid. It's the stock cable so I don't think it's too small of a gauge.

https://i.imgur.com/OJzPOHy.jpg
https://i.imgur.com/yJZSufz.jpg

For some reason I still think it's something in the starter. Perhaps the bearing went bad and it's binding up and not letting the armature spin freely creating resistance? Maybe I should just get another rebuild kit and swap it all out again. I'm at a loss right now.

 

I realise that it's a different starter, but the post is insulated in the same way. You have more than one extra washer, and if the plastic insulator was cracked then moisture or dirt (or even jumping the air gap) would cause a secondary path to ground which could cause the problem you are having if the resistance in that pahway were high enough. The motor draws a lot of current, and the insulation of the positive post is critical to proper operation of the motor.

 

I'm positive that's the correct amount of washers and order all those washers go. But yes, you're right. If the insulator is damaged inside the housing that would be an issue. I'm going to take it apart again. I did a quick once over and cleaning yesterday so it wouldn't hurt to have a closer look.

Here. Take a look at this guy's video. Same rebuild kit. Same exact starter and he installs the same amount of washers and in the same exact order as I have on mine. His video skills are crap but it is quite detailed.

Yamaha Seca ii Starter Rebuild -Will Trautman

 

So here's something I noticed today I didn't pick up on yesterday. When I spin the starter shaft there seems to be some resistance like the armature is rubbing against the case. If I'm not mistaken that shaft should spin smooth as silk. Possible bearing or bushing gone bad?

 

Or could that just be the brushes rubbing? Are they supposed to rub?

 

One thing that is cheap is replace the start solenoid , I had issues with mine before I replaced it , found corrosion inside . I think I paid 11$ for the solenoid .

 

The brushes rub against the commutator.

 

Right. I thought about that after I posted that.

Ok. So here's another thought. If I were to remove the starter and hook up a negative cable directly to the starter body and the negative post on a battery. Then take a positive cable and attach it to the positive post on the starter and connect it to the positive post on the battery. If the positive post gets hot I'll know it's the starter. That sound about right?

 

The older XJ's use a gear reduction starter so it is very difficult to turn the output shaft, however it looks like the starter on your bike is a direct input. The starter will have some drag as you turn it because of the opposing magnetic field induced into the armature from the permanent magnets, however it should be minimal under no load. If you were to install a jumper from the output post to the case it should become more difficult to spin.

I would suggest checking the commutator segments to ground - the armature shaft. All segments should be open to ground.

And from the Information Overload a good guide for checking the starter. Note as stated earlier checking the resistance with a DMM is not really practical with a standard DMM. However, checking the individual segments for continuity and particularly to ground is recommended.

https://www.xjbikes.com/forums/threads/the-information-overload-hour.27544/

Checking Starter Motors:

As far as checking your starter motor, the only tests that you can do are on the commutator (the segmented "snout" of the entire armature) and the brushes, and are as follows:

a) if the surface is commutator is dirty, clean it with 800-grit or finer garnet paper or crocus cloth. Make sure that any dust generated by this process is completelyremoved.

b) the mica insulation on the armature.....in between each of the raised "segments"......should be:

* 0.8mm (.03") below the level of adjoining segments on XJ550, FJ600, FZ600, and YX600 starter motors.

* 0.6mm (.025") below the level of adjoining segments on all XJ650, XJ700, XJ750, and XJ900 starter motors.


If the depth of this mica insulation below the level of the segments is less than the specifications given above, you should scrape away the insulation until that depth is reached (a hacksaw blade or similar tool can be shaped to fit), or take the armature to an electrical service shop to have them undercut the mica to the appropriate depth.

c) check the raised segments for continuity between each individual segment and each and every other segments. There should be continuity.

d) check for continuity between every segment (assuming the test in "c" above has already been performed) and the shaft of the armature. There should not be any continuity.

e) check the resistance of the internal coil windings of the armature. You do this via measuring the resistance across every two adjoining segments. It should be:

* 0.012 ohms +/- 6% at 70-degrees F. for all XJ550, FJ600, FZ600, and YX600 starter motors.

* 0.014 ohms +/- 6% at 70-degrees F. for all XJ650, XJ700, XJ750, and XJ900 starter motors.


f) measure the outside diameter of the segments. The minimum acceptable diameter is 27.00mm.


If any of the above tests (c-f) fails, then the armature is bad and needs to be replaced.


g) measure the length of the brushes. The minimum acceptable length is:

* 5.00mm for all XJ550, FJ600, FZ600, and YX600 starter motors.

* 8.50mm for all XJ650, XJ700, XJ750, and XJ900 starter motors.


h) check for continuity between each brush and the brush plate. There should be continuity.

i) check for continuity between each brush and its terminal bolt. There should be continuity.

j) check the condition of the shaft end bushings or bearings in the case. If they are worn, then they needs to be replaced.

k) check the condition of the ring and planetary gears. If they are worn or chipped, then they need to be replaced.

l) the only other procedure that is mentioned in the factory manual is to check the condition of the brush springs, and you are supposed to do that by comparing them to new ones.....which is kind of hard to do! The springs should be considered serviceable if they snap the brushes firmly back into position when released from tension. The exact specification is:

* 550 +/- 50 grams (18.5 +/- 1.5 ounces) of pressure, measured via the use of a spring gauge, for all XJ550, FJ600, FZ600, and YX600 starter motors.

* 800 +/- 150 grams (28.22 +/- 5.29 ounces) of pressure, measured via the use of a spring gauge, for all XJ650, XJ700, XJ750, and XJ900 starter motors.


Also, be very careful when re-assembling a starter motor. There is an alignment notch in the brush plate that must be aligned with the case properly, as well as alignment notches on the outside of the main case to the end caps. Failure to install the brushes and brush plate in their proper orientation can cause the starter motor to not work at all, or to even spin backwards! The correct rotation of the starter motor is counter-clockwise, looking at the butt-end of the motor (as it is installed on the engine); or, clockwise if you're looking the starter drive gear dead in its eye........


Finally, always be sure to use a premium, high-temperature grease to lubricate the internal gears and bearings, and do not attempt to clean the armature via the use of strong solvent sprays (brake cleaner, carb cleaner, etc.) as the solvents may break down the insulation on the coil windings, causing an internal short.


A great video of the entire process from start (no pun intended) to finish:



And though you may not have your own personal growler, follow these basic tips anyway while you have your starter motor apart for the rebuild:

https://www.xjbikes.com/forums/threads/tackling-starter-rebuild-this-weekend.123652



- TESTING YOUR STARTER MOTOR CIRCUIT:

http://xjbikes.com/forums/index.php?threads/7828

 

Remove the starter from the engine and sort it out off the bike. If there is any continuity between the hot post and the starter clamping bolts then you have a bad washer stack setup. It looks wrong to me as well. Is there a plastic spacer centered in the case wall hole?

 

Good stuff. I guess I know what I'll be doing this weekend. Thanks Rooster.

 

I have it off already. I'll be testing some things later today. Yes, there's a rubber insulator around the post that fits through the hole on the starter case through the inside when you put the brushes in. Fits right in so there's no contact between the post and the case. I checked that and it looks good. It's not rotted and no cracks or splits. If anyone can find some notes or a picture of a different washer order I'd be more than happy to try it but everywhere I look it shows them the way I have them on there.

Even all the rebuild kits show them in that order.

https://i.ebayimg.com/images/g/B80AAOSwz35bDD7w/s-l500.jpg
https://i.ebayimg.com/images/g/Pp8AAOSwFq5c2tes/s-l500.jpg
https://i.ebayimg.com/images/g/~DQAAOSwYoRdFlAu/s-l500.png