Starter issues

Ok, so I have a 1983 xj750 maxim. I have replaced the starter bushings and the starter was like new. Had no issues starting. Fre months later the battery was toast. Di I replaced the battery. I went to take it for a ride to make sure everything was good. And the bike killed on me and didn't start. The starter engages and turns but then almost immediately disengages while it's still turning. Doesn't seem like its ducking fuel into the carbs either but when I take the fuel line off the fuel runs out of the petcock. I'm lost and what to check, I've read forum after forum and nothing makes sense to me. I have also rebuilt the carbs, amateurly if I might add. But it seemed to run fine except the matter of a hesitation in the first and second gear when it's cold. This bike was running for 3 years before all this happened. Any ideas?

 

When you crank does it sound like bolts in a coffee can? The starter clutch will invariably slip my seca does this occasionally when hot . You need to provide a little more info. If it is the starter clutch you have to split engine case so engine will have to come out of frame . I bought a spare engine off another forum member at some point will have do this to my engine.

 

Check the battery. It should be at 12.8 volts when resting, and not drop much below 10 volts when you thumb the starter.
The starter clutch has to be spun quickly enough for the rollers to grab, and if the battery is at all weak the starter can't spin fast enough.
If the battery fails that test, then the next step is to check the voltage regulator to make sure that it isn't killing the batteries.

BTW. Hope that the battery is at fault, because that's the easiest problem to fix (you already took care of the starter rebuild).

 

The battery is brand new, but it is just a cheap everstart battery. But it was the one that was said in the book for my bike. I didn't look up the voltage, I'll do that. The starter sounds strong, it just doesn't stay engaged long enough to spin the motor. It always backs itself out and just spins inside the starter.

 

That sound you hear is the starter clutch slipping. Even a starter being run by a fairly weak battery, or one with worn brushes will sound strong, but allow the starter clutch to slip.
The starter clutch cannot be repaired without splitting the engine cases, which is why we recommend making absolutely sure that every other part of the starting system is in the best condition possible before diagonsing the starter clutch as being at fault.

What oil are you running? The wrong oil type can also cause the starter clutch to slip.

 

If I remember I have been using 10w40 4 stroke. That's what I was instructed to use by a guy at the parts shop I go to.

 

The key is that it not be synthetic, unless it meets JASO MA certification standards. Thankfully most of the synthetic motor oils for motorcycles seem to meet that standard now, but if you can remember what brand it is and check the bottle that would save you some work. If the oil isn't compliant then a change and flush should solve the problem.

 

I believe I used valvoline 10w40

 

Both their conventional and synthetic meets JASO MA2, so that won't contribute to the slipping. In this case that's bad news, so on to the starter rebuild if the battery checks out (even brand new batteries can be faulty).

 

Update: So I decided to drain the oil cause it started leaking all over my garage. Looks and smells like there was gas in the oil. Any idea what could cause that? Bad piston rings? Head seal?

 

Stuck float, or bad float needles.
Have the carbs been refurbished by you?

If not, then it's time to go to church.
IN THE CHURCH OF CLEAN

Replacing your Hitachi throttle shaft seals

Setting the fuel levels

 

If its leaking outside the crank case, I'm assuming the seals on the crank case are messed up as well?

 

Nope. It's just coming out of the crankcase breather, and running all over. Drain the sump, let it air out for a day, refill with new oil (AFTER fixing the float problem).
You should also check that the petcock works without leaking. Fuel should flow freely when it is set to PRI (prime), but not at all when set to ON or RES unless there is vacuum applied to the vacuum line. Petcock rebuild kits are available should the petcock not be working correctly.

 

The petcock flows freely on PRI and stops on RES and ON. So that seems to be working fine. I did do the carbs myself. Mayne I did something wrong when I put it back together. I'll pull the carbs and check it out and give you an update when I have one.

 

It's been 2 months and I was finally able to work on the bike. I bought a new air filter, new oil filter and oil. Bike took a second to start up and still wont idle right yet. But so far there doesnt seem to be any problems with fuel in the crank case. I still need to ride it around more to verify that it was just a one time issue.