My Seca 750 is making some awful noises

Yes there is play , the large hyvo chain is on the gear and you see in the picture the gears and this is what you see through the opening for the starter. Okay my opinion if your starter clutch slips it will not magically fix it's self . Yes rebuilding the starter motor is always a good idea , a fully charged battery and carbs synched all can help . The engine in my Seca was good for two years and engine had 38k on it went on a 300 mile ride by the last 100 miles could barely get it to crank just slipped . After I got home and the next day could not get it to hit at all just slipped. So did the deed one roller was galled pretty bad and the springs were shorter than my rebuild kit . I have not had any issues with cranking since i split the case and rebuilt starter clutch. The original engine to the bike had a slipping starter clutch as well 17k , I messed up and moved the crank shaft when I split the case and without the can tensioner in place it skipped timing. I still have not looked closely to see if a valve hit the piston two cylinders two and three are only showing 90 psi number one and four 130 Psi . Sorry did not mean to get off topic. Cheers

 

Slipping clutches will magically fix themselves when the slipping is due to the wrong oil. I used V-Twin 20W50 once, and the starter clutch wouldn't catch at all. Switched back to the Mobil 1 10W40 and it was fine.

I know what slipping sounds like and that's not at all what I'm trying to solve here. I'm trying to solve this hooting sound, which comes from the starter even when it's removed from the engine and I'm trying to solve that screech that's happening when the engine is running.

BTW, it would appear that what I am seeing in that photo is not the starter clutch, but is actually the idler gear. The clutch seems like I would need to pull the alternator rotor to be maybe able to see it.

 

OK. So, I've got the clutch plates out. Just want to verify where this bearing and collar go. I should have the parts tomorrow. Is this bearing behind the clutch basket - i.e. I would need to remove the 30mm nut, or are we talking about the flat bearing and shim that sit on the clutch rod?

 

There is slight side movement in the alternator starter clutch shaft l believe that is what it is. You might be able to check it but you would have to remove the alternator cover and stator. Then try and push pull on the rotor. Behind the alternator rotor is a bearing housing held by three torx bolts. Don't take that out to see the starter clutch incase the shaft comes with it. Then the starter clutch unit would then be loose in the crankcase in the pictures below. @tabaka45 post shows the seal replacement here, all you can see is the starter clutch chain and sprocket. Hope this helps.


https://xjbikes.com/forums/threads/...ith-pictures-applies-to-all-xj-models.108126/

 

You have to remove the 30mm nut to get the collar and bearing out. And on reassembly make sure the tabs are in their slots as this is how the oil pump is driven off the clutch basket.

 

Yes it is the idler gear, the starter clutch is behind the alternator rotor.

 

The bearing sits between the sleeve in the photograph and the clutch basket.




Needle roller bearing and sleeve below

 

I replaced the bearing and the collar. Both original parts looked fine. Then, after reassembly, I couldn't get the clutch to release. So I took it apart again, and removed the pressure plate, and it just seemed that a wet clutch with no oil is pretty sticky (I had tested release (or not) by putting it in gear and seeing if I could turn the back wheel with the clutch pulled in).

Anyway, after figuring/hoping that it would be better once there was oil in there, I put it back together again and could not get two of the pressure plat bolts to take the 7.2lbs of torque they're expected to take. Then one snapped.

On the bright side, the remaining piece of the bolt came out pretty easily. And I also have a suitable replacement on hand. On the not so bright side, I guess I'll need to helicoil at least two of those bolt holes. It was $32! for a M6 x 1 kit at Autozone, and it only came with three inserts, and not even the punch. For less, on Monday, I could have had a 131 piece thread repair from Amazon. The price of convenience...

So, going to take another stab at it now. Hopefully it goes smoothly from here.

 

OK. Rethreaded the two stripped holes, replaced the one broken bolt, and things went back together well enough. The clutch feels fine, and, sure enough, once some oil was in there, it released correctly. The bike also sounds fine, now. No idea if the bearing was really bad even though it looks OK. In any case, no screech, no hooting,... just the normal noises.

 

The bearing in my bike was exactly the same. It looked in good condition but noise disappeared once it was replaced.

 

When I stripped mine I found the bearing inside the oil pump drive sprocket (the narrow roller one) totally worn out - the rollers had flats on them, like they had been skidding around...

 

I checked mine when l had the engine dismantled and the oil pump one was fine. Do you know how many miles your bike had done?

 

Spoke too soon. Took the bike out for a ride. When I got back I turned it off in the driveway and went to open the garage door. When I restarted it, it was making a very clear whirring sound. I tried it a couple of times, and it kept doing it. Then after maybe the third try, it stopped.

I do think it's the starter clutch, and I think what's happening is that it's getting stuck engaged and driving the starter.

Or... maybe the solenoid is sticking? Would a stuck solenoid be enough to keep the starter engaged through the starter clutch? The whirring sound definitely varies with engine speed.

Edit: actually, a sticking solenoid doesn't make sense. If the solenoid were sticking, the starter would have continued cranking after I shut off the ignition switch.

 

That is unfortunate. I am not the best at electrical problems but if the solenoid were sticking how can the starter still crank when the ignition switch is shut off as the power supply to the live feeding the solenoid pigtail should be cut. If for example the solenoid was not working at all with the ignition switch on and power at the pigtail then jumping the solenoid contacts with a screwdriver should operate the starter motor. As I understand it on our XJ's the power flows from the battery to the main fuse then to the handlebar switch where it is distributed to the rest of the harness via the other fuses, although some wires are spliced together withinn the harness according to the wiring diagram.

A check if you can make sure nothing can get sucked into the crankcase is fitting a metal blanking plate of some sort over the starter motor opening and bump starting the bike a few times to see if the noise stops.

 

I suspect around 45k, but it's hard to be sure. I can't quite get my head around how this bearing might wear in this way.

 

Yes it's not got a lot of load on it surely turning the oil pump.

 

No, that's incorrect. Power to the starter comes directly off the battery. The low current trigger to the solenoid is through the fuse box and ignition switch, but the high current side is not switched or fused. If you have a Haynes manual, take a look at the right side of the page where you will see the heavy line going from the battery, across the solenoid, and to the starter.

If you still don't believe me, just pull the side panel off your bike with the key off and jumper the two large contacts with a screwdriver or wrench... the starter will crank, but the bike won't start because ignition is disabled.

To be clear, a sticking solenoid is one that stays closed after power to its coil is removed.

 

Lol yes you are correct of course the heavy red wire from the starter goes to the solenoid. All l had to do was look at my bike before my last post. If the signal wire was in place of the heavy red wire with the current the starter motor would draw would cause the wire to overheat. Told you l was no electrical guru

 

Well... some unhappy new developments:

I rode to work today. When I was ready to head home the bike started fine, but I thought I maybe heard that whine like I'd heard before. I went see if the start button might have been stuck in, and, I guess I must have pressed it. I heard a clunk from the engine and it died. The starter now has difficulty turning the engine, and it won't start. Attempting to bump start it doesn't work at all. Even with a decent downhill slope the bike just stops when dropping the clutch. Waiting for a tow truck now.

 

Next steps are going to be to pull the starter, to see whether it's damaged... if I can even tell... and pull the alternator, so I can at least get a look at the starter clutch, but, at this point, I'm pretty resigned to pulling the engine and getting invasive.