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webmonstro 5 Feb 2014 21:49

Sounds like your starter clutch is slipping and your not getting it up to speed to get it started

steveloomis 5 Feb 2014 21:54

I have seen starters, not bike starters, that had copper bits filling in the space between the commutator sections. New brushes, under cutting the insulation between and spinning the commutator in fine sand paper cleaned it all up. New bearings are good too, if you have them.

The starters that were clogged as above would just barely spin the engine if at all and take lots of power doing it. Obviously the commutators were shorting out and adjacent sections fighting each other.

Good kit above...

fireblade123 6 Feb 2014 09:16

Thanks guys for that, if I had any doubts about the brushes I would have replaced them, the com was ok.but I cleaned it up, the mica was undercut ok. I maybe should have checked the windings. I am waiting for a decompressor cable and bracket coming so I can get it started, I'll see what it's like when it's been run. Maybe the motor off again and get it checked out professionally.
Thanks again.

fireblade123 6 Feb 2014 09:42

Quote:

Originally Posted by Mezo (Post 453403)
Used starters are plentiful on ebay anyhow, especially ebay.de

Mezo.

Used electrics are always a risk though as I found when I suspected the CDI. I bought a supposedly guarranteed one on ebay, good money too, still no solution so I looked elsewhere for the problem, waste of time as it was in part the CDI at fault, as was the replacement, got a refund but is it worth the hassle.

webmonstro 6 Feb 2014 10:31

make sure it's not this problem :

The Ténéré Forum • View topic - 3AJ starter clutch

fireblade123 6 Feb 2014 10:42

Quote:

Originally Posted by webmonstro (Post 453419)

Does it sound possible, it isn't that the starter motor is spinning fast and the engine not responding as you would expect with a 'slipping 'clutch?.
Cheers

fireblade123 6 Feb 2014 13:32

Quote:

Originally Posted by Mezo (Post 453337)
Well i had a couple of mates on 1VJ`s turn up, one bike fired up "on the button" the other just died every time & he had to always kick start it.

Your lucky that the 1VJ came standard with both kicker & electric, god only knows why Yamaha did away with that idea & just went electric?

Well personally i would have fitted a new set of brushes whilst i had the thing apart, the aftermarket brush kit is not that expensive, although when i did my starter i went with OEM as i was getting an order from Boats in the US anyhow.

This is a very comprehensive kit, comes with everything you need.

http://i.ebayimg.com/t/Starter-KIT-Y...wpfQ~~60_1.JPG

Mezo.

Contacted the suppliers of this kit, not suitable for my motor apparently.

Jens Eskildsen 6 Feb 2014 21:31

Yeah, I'd think they would fit all models.

fireblade123 16 Feb 2014 13:40

Skip fodder
 
I am at a stage now where I am ready to bin this bike, fitted the decompression cable still can't get it to start. Good spark, good compression, carb stripped & cleaned, fuel to the plug ok [as far as I can tell]. I have put the starter motor/clutch on hold until I get it running ok. Just at a loss where to go next. Don't have too much time to waste with wife ill. Never had a bike beat me in 50+years.
Cheers.

I seem unable to open/read message in PM for some reason.

fireblade123 17 Feb 2014 09:12

Quote:

Originally Posted by Mezo (Post 454805)
Does it smell of fuel? is the plug wet? bit of a this mystery this one, you should be able to kick start it fine so the e-start can wait.

Mezo.

Thanks for you help again, I too am at a loss. Have stripped and cleaned the carb, diaphrams ok. Fitted new replacement CDI unit, had stator rewound new plug/lead/cap and coil. you can understand my frustration. plug fires ok when earthed outside the head, wet when removed after attempts to start. It did start once and ran ok but never since??.

fireblade123 17 Feb 2014 11:42

Quote:

Originally Posted by Mezo (Post 454851)
Got me stumped? you have fuel & spark so it should do something??

Are you getting the faintest of running, the odd cough, bit of combustion smoke out the pipe? im at a loss on this one.

From what you have said i understand your feelings of throwing in the towel, cant help feeling this is a carbie issue though, is the choke working?

Mezo.

The choke was seized, that was cleaned and lubed, blown through, the vacuum attachment to the manifolf had been bodged, that has been fixed with new vacuum pipe. I too feel that it is a fuel problem, all I can be sure of is that the float chamber if filling, as I said before the plug is wet when taken out after attempts. When I bought the bike a couple of years ago it started fine, since then it has been stood until recently.

steveloomis 17 Feb 2014 14:31

My own experience in dealing with my XT is the fuel/air must be pretty close or they get very difficult to start. Even feeding throttle during the kicking process mess's up things. I've resorted to full throttle kicking to clear it out, then sitting and waiting too.

Did you check you intake carb to head boots for leakage. They get hard as a rock and leak air. I have only rebuilt the older 80s carbs so cannot speak more than generally. Usually there is a brass emulsion tube under the main jet that can be removed. If so, check to see that none of the side holes are plugged. If they are, then your mixture will be rich. Verify every single passage is clear, use a tiny wire if necessary to probe the passages. Check the float level with fuel and a clear tube from the bottom drain up the side of the carb. Should be about 6mm below the flange of the float bowl, verify this setting for your carb type.

fireblade123 17 Feb 2014 14:52

Quote:

Originally Posted by steveloomis (Post 454874)
My own experience in dealing with my XT is the fuel/air must be pretty close or they get very difficult to start. Even feeding throttle during the kicking process mess's up things. I've resorted to full throttle kicking to clear it out, then sitting and waiting too.

Did you check you intake carb to head boots for leakage. They get hard as a rock and leak air. I have only rebuilt the older 80s carbs so cannot speak more than generally. Usually there is a brass emulsion tube under the main jet that can be removed. If so, check to see that none of the side holes are plugged. If they are, then your mixture will be rich. Verify every single passage is clear, use a tiny wire if necessary to probe the passages. Check the float level with fuel and a clear tube from the bottom drain up the side of the carb. Should be about 6mm below the flange of the float bowl, verify this setting for your carb type.

Thanks Steve, I have checked everything over and over, the carb 'boots' are fine, new 'O' rings fitted just in case, everthing is spotless, all orifices cleaned out with compressed air, again, over and over. The float level is fine. The problem seems to be too lean a mix if anything, when removing the carb after yet another mad kicking session everthing inside the head, valve stems etc. is quite dry, no real sign of fuel, really doing my head in.

steveloomis 17 Feb 2014 21:27

I know this is unlikely but could the cam chain have jumped a cog. Exhaust every possibility. Is your spark a good strong spark or kind of spindly?

I looked back on this thread and see you got the stator re-wound and a replacement CDI. Was it a new unit or used or aftermarket CDI. Is it the CDI with all the pig tails on it or the newer TCI with the plugs built-in?

The reason I ask is my 86 would start after many kicks, the spark was not too strong. IT ran but not the best and backfired plus it had numerous oil leaks. I put it in the shed last winter and started thru it replacing seals, removing the rockerbox and resealing, setting valves, cleaning carbs. the whole gamut. When I pulled it out to start it, no spark at all, my spare 84 xt's cdi was dead too so I tested everything I could to verify my stator and trigger coils were outputting, they were and the ohm readings were pretty close. I ordered 2 replacement CDI from Hyperpak in New Zealand and forever later I finally got them, plugged one in and I had a good healthy spark. With just a few kicks it started and ran better than it did in a long time. I took the other CDI just temp plugged it in 84 bike and it had good spark too.

So I say all this to show that the CDI's can go dead or almost dead just sitting around. I think the components go bad, capacitors dry out etc.

fireblade123 18 Feb 2014 13:14

Quote:

Originally Posted by Mezo (Post 454926)
If that is clear start working your way backwards, it could be crap in the fuel pump (also common) so you could pull the pipe from the fuel pump & divert it direct to the carbie bypassing & ruling out a faulty pump.

Check you have good fuel flow out of the tank before fitting it to the carb, you will need the tank filled to over a third for this to work.

If the fuel from the tank is poor flowing with it having a good amount inside it could be the filter on the petcock itself blocked.

If after all that & still nothing then i would suggest you have a blocked jet, its the only thing logically it can be.

Mezo.

I have a remote tank fitted for convenience, strung from the ceiling bags of flow. Good pressure from the pump, all the jets are clear. I initially checked the float level from the book but after Steve suggested the clear pipe method I found the level to be low, I adjusted it, no difference. After replacing the carb. today it did seem to try and kick me through the ceiling, I kicked it over on full throttle in case the plug had got wet, it gave quite a backfire but still not starting. I am sure it is a fuel problem, as the plug is wettish but not as wet as I would have expected after all the tries. Steve mentioned valve timing may be out but it has started once but I had to switch off because I had removed the oil bleed screw and oil was pumping all over the place. At least I know the pump is fine. I appreciate all the help from you guys, makes me feel I am not on my own with this problem, just don't have as much free time as I would like at the moment.


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