XJ750K starter?

Ok, so I'm one problem away from picking up an 83 XJ750K from my friends dad. One problem, I can't get it started. Tried replacing the starter solenoid, when I press the start button the solenoid clicks like it would when you start it, but it rarely starts. I replaced it but it does the same thing. So I'm thinking maybe its a starter problem or something. Any ideas?

 

Battery?

 

First off, welcome.
Next order of business, you mention that the solenoid clicks but "it" rarely starts. Could you describe what "it" is? I'm assuming the starter motor but the write-up is a little vauge. The engine? More details please.

 

So it does start sometimes? or does it just click?

Fully charged battery or try carefully jumpstarting. If it then starts you have found your problem, but if it then turns over fine but will not fire try a new set of sparkplugs esp. if it has been sitting for a while.

 

Pull the Crank Cover and put a wrench on the flats and see if the Engine WILL rotate!

 

I think you mean timing cover.

 

Timing cover.
Crank Cover.

The one that tells you if it will turn or if its toast.

 

OK, I know the battery is good because all the lights and everything work fine and I've tried charging it several times. When I go to press the start button to fire it up i usually just get a click from the solenoid and nothing else. Once in a while the engine will start right up like nothing is wrong, and it runs great, but this happens very rarely. I haven't tried jumping it off a car yet, but like I said I have tried charging the battery. I am very new the the motorcycle world, so a detailed explanation would be very much apreciated. Also, how would I pull the timing cover to try and turn it over?

 

solenoid has 2 large terminals with nuts on them one goes to the battery +
the other to the starter
turn key on, and put a wrench or a screwdriver between these terminals
be prepared for some sparks
what you have done mechanically is the same as the start button does electrically
if this works every time the solenoid or its wiring is the cause
if it doesn't the starter needs work

 

Also, how do I go about cleaning out the starter? I read some stuff on other forums about cleaning the starter out and that solver a lot of problems.

 

We don't need to turn it over if it actually does run.

Let's get you on the Fast-track.

Use the "Signature" section of Your Account and provide us all with some "On-screen Thumbs about the bike.

_____________________________________
Year....Model....Total Miles....Stock or Modified....(Starter Issue)

When I get a real old bike and hear the Solenoid Closing ...

I pull the Starter and see if the Starter takes a spin off a Battery Charger.

Then ...

I clean-up the Starter
Clean and Waterproof synthetic grease on the Planet Gears and Shaft on the business end.

Flush-out the Dust and get a peek at the Commutator on the Electric end.

Sometimes it's just so dirty it hates the idea of working right and getting your bike started ... just to jerk you around good.

 

Alright, this is sounding like some good information. What kind of fluids am I going to want to use to clean out the starter? Also, where exactally is it located on the bike, I'm assuming I can just follow the wires off the solenoid.

 

Ok, good question. Where is the starter? Do you possibly have a maintenace manual or the XJCD on hand yet? No? First purchase you should make when it comes to repairing your own bike. It WILL pay for itself within the first two times you use it.
Now, back to the starter. Your starter is located just under the carburetor bank just in front of the bottom of the air box on the left side (you sitting on the bike) of the bike. Just atop the transmission housing sitting to the rear of the alternator. It is secured with two very long 10mm head-ed bolts. Be sure to disconnect the battery before you attempt to pull the starter, you'll be glad you did. Nick, you got a picture handy?

 

Quick question for rick, how do I see if the starter will take a run off the battery charger?

 

OK update, I tried putting a screwdrive between the terminals on the solenoid, I got a few small small sparks but it definately wasn't doing anything to help it start. So I guess I'm gonna take the starter off and open it up and try to clean it out.

 

Here's what it looks like.

Sorry I don't know how to make it larger.

 

Thanks a lot, I really appreciate all the help. Now, am I gonna want to dissasemble the entire inside of the starter and just clean all the parts by hand or what?

 

If you shorted the solenoid and nothing or little happened, your starter is the culprit. Pull that puppy. Clean and lubricate it and then jump it with an external battery to see it spin. Don't run it more than 10 seconds or so at a time lest you start cooking it.
To test the starter, you should connect the positive voltage terminal (located on the top/side of the starter) to the positive (red) terminal of the battery and then, away from flammable materials, touch the negative side of the battery to the case of the starter. It should spark, but more importantly, it should spin with startling speed.

 

This should help ~)

 

I had this happen on my 750K. Turned out to be starter brushes. Minimum length is 8.5mm. I had one that was 8.3mm. They are serious about the length! If you find oil when you pull the starter then change the oring at the end of the starter case. Denso makes a brush and holder replacement but it costs about $35. It is part# 028510-0651. Benefit is that you don't have to solder the brushes in if you lack good soldering skills. Otherwise, brushes alone would only be about $10.

 

OK, so I pulled the starter cleaned and re greased it. I just tested it with some jumper cables. My cables are pretty crappy but when I could get a good connection it sparked really well and turned over. I won't be able to put it back on the bike until tomarow, but do you guys think it should be good to go? Well, here are some pics anyway.

 

Good pics, I sure hope you took all that carbon powder out of the brush end of the starter. That was quite the collection in there!
How were the brush lengths? BlueMaxim had quoted some specs for you.

 

Way too much carbon fluff in there, you might (reads: will) need new brushes asap! Good job cleaning up, fresh grease is always a great start. Was everything right where I outlined and could I have improved upon my directions?

 

Yeah, I got ALL of that stuff out of there. I couldn't find something to measure in Millimeters with so I'll just give it a try tomarow. I drive past a huge motorcycle junk yard on my way to work everyday so finding replacement parts should be pretty damn easy for me. And yes, the instructions you gave me worked great, thanks a lot. Well, wish me luck tomarow, I'll have an update either way.

 

Alright, I put the starter on hooked it up and the bike fired right up! Can't thank you guys enough for all the help. I'm sure you'll be seeing a lot of me on here.

 

You need to have a look at your signature.

I believe "starting issues" should be replaced with "bugs in teeth".

 

Good call.

 

Alright, I'm still having some issues with my starter. It had been working really good for a while. Then it was having troubles turning over when the bike was still warm, so I took it out again and re cleaned all the electrical components and cleaned and re lubed everything else. It worked fine for a couple of days again. Now its back to not turning over again. I still get the clicking noise in the solenoid but it won't turn. One of the brushes inside the starter is a little shorter than the other so I'm thinking I just need to replce those. But I thought I would come here first to see what other people are thinking. I'm still going to take it apart and re clean and lube everything to see if that will work so I can at least get the bike back to my house since it is stranded at work right now.

 

Ok, I took it apart again and cleaned it all out. Here is a pic of how much shorter one brush is than the other, could this be the cause? (The brush at 9 O'Clock is the shorter one) Also, i put it back together after cleaning and tried to jump it off my car battery and nothing. All the gears and everything rotate very smoothly so the problem must be in the electical part, not?

 

When you have the armature in place and put the brush holder assembly in place, is there any tension on the brushes?

They really don't look long enough and I'm guessing those brushes barely contact the armature.

If you have an automotive starter/alternator repair shop in your area, check and see if they have any repair kits in stock. I know our small town repair shop stocks them, came complete with brushes, and bearings.

 

Brushes!

That there one on the Left, ain't makin' it ... so-to-speak.

Use some electrical parts cleaner and a handful of toothpicks and clean-out the spaces between the contact points on the commutator.

 

any results? Did you change the brushes and have success??