1990 xt 600 won’t start
 

My bike sat outside covered for 2 months cause I was doing stuff in the garage. It was warm outside then started to get cold. Well took some time to get started but started I left the choke on for about 2 minutes then a little backfire then stalled. I tried starting but no good. It was my daily driver in NJ from March to November. Now I want to get her going now. Any suggestions. I do have a manual. The boots were changed a couple years ago and carb to were rebuilt. Also the bike ran good before it sat out side. Thanks for your help

Dont worry i will help you! First remove sparkplug and check for spark testing this. If you have spark next i will check carb, remove and clean up, take out filter inside and clean, blow air all passages in carb, check carb joints again, if its china aftermarked they crack after one year.

I used oem on everything for this bike cause I heard stories. Will start there

Ok. Starting to work on this. Checked plug well installed new and felt a spark on my hand so I know there is spark. Took air cleaner off and put starting fluid in the box so the fluid can get into carb. Try starting just cranked. Any help

Well hold on I felt the spark but I don’t see a spark on the spark plug and it’s new cofusing

Battery?
 

My '89 did not like it's 2 year-old battery. It would turn over and spark with the old battery, but not fire up and run. New battery = it started.

Just checked the coil ok resistance 5 ohms now checked the coil and plug wire to neg of coil nothing also took of spark plug adapter I have no ohms either can both be bad. any help thanks

Trying to locate both coil and spark plug adapter. Forget any thing coming from Japan at least 3 months. Also do you think I am right with the testing also do you know what would work like a cross reference. Thanks

Search ebay for spares, i dont know about your reading. Insert plug in cap and hold it against ground, turn engine look for spark. Ebay search: yamaha xt 600 ignition coil

I have a manual and used the ohm reading and only got reading on the primary on the secondary to the negative and the plug wire. Did try the plug to the head nothing Just orders a new coil and plug adapter for 113 dollars shipping too. They had It in stock. Am I doing something wrong. Thanks

Always good to have on extra even if its not the problem, old bikes and electric components dont last forever, good luck!

Now I ohm it out and now it’s good getting puzzled now tried the spark plug no spark at the plug but I get wrapped. Any possibility that something is grounding out

I am getting fuel from the tank to the carbs. The bike sat for 2 months outside with a cover on it and tender on it. Took a bit to start but started then ran for about 2 minutes on choke then stalled tried to start and then she just cranked and that is it. Getting frustrated

If I do have Spark is there any way to see if gas is getting into carb to fire up

From the left side you should see a drain screw under the float bowl. See what comes out of there .

You have a dry plug going in, try fire up and keep pulling throttle several times and pull plug, it should be wet smell petrol.

Seems like I am jumping all over the place. Next process is gas

I will give that a try hooking up tank But thinking about this the other plug was dry but will try again when I was cranking

When I took the spark plug out I had very good compression I can feel it with my thumb and also I can hear it

I have $100 manual from yamaha for this bike it doesn’t tell you anything about the CDI how to check it to make sure I’m getting good enough spark it’s a shame

Well, a thump and hearing dont tell you anything, use a compression instrument gauge.

Thanks. I am aware of that however at least I know that the piston is moving for now.

Take the plug out, dump about 10 ml (2 teaspoons worth) of fuel straight down the plug hole, replace the plug and kick it over. If it fires - even for a couple of seconds - you've got a spark. If you've got a spark then it's the carb.

My best bet is this fuel. This may be a case where youur fuel system is partially blocked. Typically this happens in the carburettor's fuel intake or the lowest part of the fuel line relative to the height of the carburettor's fuel intake . What happens is that the partial blockage allows for fuel to seep past the partial blockage when the engine is shut off for a while (or under very little load) - creating a "reserve" that will last for seconds or minutes, all depending.


Unleaded fuel has a short shelf life, and more so under certain conditions than others, and more so for certain types if unleaded than others. As we are talking a carbureted bike, it is an older bike which may have seen many periods with old gas in the fuel system. Combine that with a half filled tank (air) and a bike left outside or other unstable climate (condensation, etc), and the negative effects increase. Combine that with debris in an old tank, and the fuel system can seriously gunk up.

The good thing is that the most difficult gunk settles low and doesn't cause havoc throughout your system - only in one or a few very concentrated areas - where gunk can gravitate to the bottom. I had one very bad case where I had left a scooter for two years untouched, under terrible conditions. The gunk had turned into a plug as hard as plastic inside the lower part of the fuel line. After extracting the plug using a regular screw, the problem was solved.

Clean your carburettor thoroughly and check that the float actually floats freely (sometimes the plastic can crack and fuel seep inside, and other issues). Check for gunk in the lower end of the fuel line, clean mechanically and flush the line. Using compressed air or liquid through the line (both ways) is a good idea, if not too inconvenient. Since you are already into this mess, it is a great opportunity to replace the fuel line anyways - maybe into one with metal hose sleeve to prevent vapor lock?

Great thanks. I ordered up a coil and a new spark plug adapter just in case. I just want to be careful of gaskets cause parts are hard to get cause of parts supply and shipping. Will fill you in on progress

The best way or easy way to get the carb out. I had it out about 8 yrs ago. Don’t remember the struggle but will try the spark first, what I will try is cut the spark plug wire back then screw the adapter back on and give it a try. Wheelie you might be right cause I did leave it outside covered in the cold until I put it in the trailer, it did start up for me to put it the trailer but it stalled out after 2 minutes on choke but it was cold out that day so I tried to start it back up and the bike just started to crank so filled the bike up with gas and stabilizer and away she went. The is a good runner never had any problems with her basically all original except for the carb rebuild and intakes.

Its fast and easy pulling carb, loosen all clamps, loosen screw battery case, 4 screws on top airfiltercase,remove cover over airfilter, rubber moutning in back, then just pull carb out towards stand side, need correct angle, the airfilter case must be pulled back when doing this. Its rubber gasket in bottom carb for reuse.

Tested the pick up coil tests good. I put some gas in the cylinder to check for spark nothing. Now I did cut the spark plug wire back and I installed the spark plug adapter back on. Before that I did on all out it test good. But still don’t get a good spark on the plug. I did ohm neg of the coil to the spark plug adapter no reading but when I do them individual nothing. What I am going to do is get is a spark plug tester that I put on the plug and the wire to see if there is a good spark. Should I check the valves next. Any help would be appreciated. Thanks x again

Is your lead/cable to the plug good? They can fail.

I ohm it out from the neg side of the coil ( which is where the orange wire goes to ) to the cable, I did take the spark plug adapter off cause the manual said so, and ohm out good. The next try is putting a spark plug tester that plugs into the plug and then into the adapter and we will see what happens. Now when I tested the coil I left it in the bike and took off the orange and black wire and ohm between the + and ~ to see the readings all good

Well bought a spark plug tester And there was a light on the tester all good there. Well maybe it’s time to take the carbs off. Anything else with electric thatvI should check. Possible grounding?

So I guess will pull off carbs now

Xt thanks for the info on carb all worked out Took carb apart and there was some gas in the carb. But I started to blow into the tube where gas goes in carb might I say might of been a blockage Can I use carb cleaner on the passages if so the orings will they be ok. I want to only do so much cause the parts are tuff being of the shipments. I can order later and redue again. Also float bo was clean and the screen had maybe a little but I am surprised no dirt in the bowl. Any other suggestions please send. Thanks again

No problem using carb cleaner, remove small filter under valve, screw holdin in place, when having open the bowl. Be careful wigling this out, its not the strongest metal brass. Remove pin first holding needle for open close petrol supply, hanging from float device, then remove brass filter, maybe wanna order new to replace with needle. Be real careful prising pin out so you dont break the pin holding legs! If you do its trash..Search Walmart. Com you find rebuilt kit motorgenic carb Yamaha xt 600

Yes sir took it all out all good. Where the screen was there was some debris there but looked okay. Cleaned out tube where fuel goes cleaned might of been blocked cannot say for sur but gave it all a good over. Cleaned out jets and those little passages.

Did you check that the engine kill switch isn't faulty? Ignition switch?

Does the bike have a full petcock / tap as standard or an aftermarket one? They can gunk up, as can aftermarket online fuel filters.

Is your problem two fold, no spark and no fuel, or just one?

Great, read this Thread, maybe same problem
Engine cuts out
theoneandonlymin

Rock, I did read that article however so what your saying if the neutral switch is bad it would not start however mine is turning over. I thought that these safety switches are part of the ignition switch so they all have be closed to start or I should say turn over the motor as the push button is pressed Now if it’s cutting out I can understand there being a problem with one of the safety. But I will look into the switch for corrision because that will give me a voltage drop. I am going to check an clean all too

Just saying go over and check all components if you are missing power to coil, as the other thread we are on the transmitter for timing, just measure all so you know all are ok. Its the only way findding problems, good trick pass out all safety when its not turning. For now, get all togheter and try start up.

Neutral switch was the problem

Installed carb checked connection still cranks over but not even a back fire. I jumped out the relay for starter same.

Having a hard time checking valves. I see the rocker arm going up and down. Trying to get that feeler gauge in there. Now checked the manual I see as I turn the bolt counter clockwise 1-1 then 1, I line up that notch on the 1 correct there is no t on my flywheel correct. Thanks I think I’m giving up for tonight cleaning up

I did look at the video for the adjustment , maybe it’s that cdi box. The bike was running and stalled and then it doesn’t start back fire like it ran out of gas and that’s it. Now the neutral safety switch if that was bad it would not turn over correct. Thanks for all the help.

Valves dont go out of adjustment over night, they start making noise or go quiet if out of spec. Read thread Stillben xt600e no start, we been trough everything, start checking pickup coil.

Thanks Rock for not bailing out on me. I am going to take carbs out again and did not realize that the secondary carb has a main jet. Maybe that will help. But before all that I will keep cranking to see if there is fuel at spark plug when I take it out. The pick up coil ohm good. If I turn the ignition on I should get 12 v correct. The primary coil ohm good, the spark plug adapter ohm out good, the stator ohm out good even nothing to ground shorted. I did get wrapped from the spark plug wire when I was holding the spark plug against the motor with a set of pliers. But spark is hard to get against the motor. The battery is load test full chart and new but again it started then died. Do you know if there is anyway to to check to see if the tci is good. I don’t even see how to open it.

You say you don't have a spark. It could be the CDI - I've had this happen on a different bike, given the same symptoms.

I agree with the comments regarding valves. To me it sounds like you have an electrical problem - not fuel, air or compression.

You can probably rule out the ignition switch as it is turning over, as well as the starter relay, etc.

If you can set the kill switch to off and that also cuts out the starter switch (won't turn over), then you can probably also rule out the kill switch (some bikes don't have the starter and kill switch connected). If the engine still churns with the kill switch off, then it is worth checking the switch.

I don't see how the neutral switch has anything bro do with this. If anything but giving you a N light on the dash, it could on your bike be wired to prevent you from being able to run the starter in gear. As you say, it churns. Ergo, not at fault.

I've had spark plugs leads fail in several machines before, and sometimes in the middle. But if you've measured the continuity, and you have good contact, you should have seen a spark. You can probably rule this one out.

Your guess that it could be the CDI is a pretty good one I think. In fact, I think it is the most likely culprit from the intel you've gathered so far.

If you have a fuel problem, it is gunk or the pump... as you have ruled out the carburettor. However, it is unusual that you get a 100% blockage over night. Usually you will have a trickle of fuel, which will at minimum let the bike sputter for a few seconds after having rested for a while. Anyhow, testing if fuel is getting to the cylinder, and working yourself backwards, is usually quite simple.

Does anybody know of a coil that I can use temporarily just to see if I can get a bike to start because the coil is going to be coming in at the end of the month I’d rather check for something now just in case if it’s not it I can start doing more testing somewhere else like the CDI thanks again

Checking again, I checked the coil to the spark plug cap and got 23 ohms on the 200k scale. Does that seem off? thanks.

You have manual and it says spark plug cap 10k ohm at 20degree C, coil -+ 3,4-4, 6 ohm, sec coil - coil + lead on plug lead 10,4-15, 6k ohm.

Check the valves intake and exhaust they were tight at tdc. They seemed real tight by means the could not even get the feeler gauge on them. So adjusted valves still no start. Any other suggestions

Sound to me like you have adjustet on wrong top dead center, just not possible that bike was running if valves didnt open before. Never adjust before you can get feeler gauge down!

There were 2 marks as I was turning the nut, then the 3 rd mark, I even checked the piston for tdc and then the mark was right on the notch.

I did watch that video and had the same marks mine looked like l-l then l which I lined up to the notch the last mark. I did check the piston and it was up to the top. When I checked the intake it was very tight with the feeler gauge so loosen up and adjusted same with exhaust valves adjusted. I don’t remember when the last time the valves were adjusted that is why I tried that too.

360 degree again and it would be correct, If all was closed. I dont know, first you write couldnt get feeler gauge in and now it was tight? Did you use correct blade thickness?

I am sorry for being confusing. What I did first was put everything at tdc and I checked the intake valves first and I noticed that the feeler gauge was to tight ( using the spec from manual)and I could not get it in there so I tried the exhaust same even with a smaller size. So what I did was tried the piston up and down and got that at the top and I did notice that the mark on the inspection cover was right on. So still noticed that the gauge was way to tight to even get in there. So I adjusted per the manual.

You could be 360 degrees out on the crankshaft?
The easy way to check the camshaft is in the correct position to adjust the valves, is to rotate crankshaft to the point where the exhaust rocker has is just finishing closing and the inlet rocker is just starting to open, then rotate the crankshaft 360 degrees. It is now at the top of the compression stroke and the valves can be adjusted.

Bob

How does this happen ? I just lost you. Also if I go to tdc why can’t I just adjust them also how do you know this happens

For every 2 rotations of the crankshaft the camshaft does 1 rotation.
You must adjust the valves at TDC on the compression stroke(when the valves are closed), not TDC when the valves are in overlap(not fully closed).
The compression stroke occurs every 2 crankshaft rotations.
You can google "4-stroke cycle" for more info.

Bob
Certified Mechanic for 30 years

Your right on that. The manual said turn the crank counterclockwise till the t Is aligned and adjust. If so how do I know if it is on the compression stroke. Also is it on the compression stoke on the intake or exhaust valves. Thanks for your help

Its like i told you in the beginning, if you cant get feeler gauge in you are on wrong turn of tdc, if you had gap its ok, NEVER adjust if there is no gap!Look inside you will see different position of camshaft.

Well I guess I thought they were to tight and needed adjustment. So I guess I will start from scratch then and give it another try. So basically is that if I did it wrong then I can correct without damage correct. When I look at the cam I should be at the lowest point and at tdc instead of tdc at the highest. In the beginning I went by the manual not realizing the 2 different strokes. I just want to set that up and see where I am. Thanks

So guys if I screwed up let’s get me back on the right track. Start from scratch. Now say everything is loose intake and exhaust valves. Which should I do first and to watch for as I rotate the flywheel. Basically what I am saying get me on the right track. Thanks for your patience everybody

Its not very complicated, if you adjustet on the correct tdc you turn 360 and check for play, if no play its ok. You write earlier adjust with play so you must have been on correct tdc, dont worry.

If you did it wrong, yes you can correct without damage.
Another way to find the correct TDC is to remove the spark plug & put your finger in the spark plug hole, rotate the crankshaft until you feel lots of pressure on your finger through the spark plug hole. You are now on the compression stroke. Continue rotating the crankshaft in the same direction approx 90 degrees(1/4 turn) until the TDC mark appears. Then adjust the valves.

The rockers should be contacting the cam lobes at the lowest point, and at tdc. With the cam lobes facing downward.

Bob

Thank you for your patience. Usually I don’t panic but I normally don’t put a bike away if it’s not running. Unfortunately I thought basically a easy fix cause it just stalled out. Waiting for the coil to come but I want all this done before it comes. Still going to check the carbs again check the rubber diaphragm this time in case that has a tear and check the secondary jet.

Update. The bike started when I put the new coil. Now the old coil tested good. Now just have to do the valves and see what happens. I will keep you updated on this. What I did notice is I installed a temporary fuel tank. I used a clear hose from the plastic bottle to the carb. What I noticed is that the fuel went into the carb and stoped. But there was a big air gap from the bottle to the carb like a air bubble, and there was still gas in the jug . Maybe there is something that is causing the bike to stall in the beginning. But changing the coil did start the bike. Is there any idea. Thanks again for your patience

Bubble man now worries today? ;-) Sure it just came bubble up when carb filled up again, should be good to go now?

Back on the road again. Ready to go all button up. Thanks for your help all. After all this it was the coil and I test everything. The coil tested good too.

Great!
 

I have been following this thread - am no "expert" on XTs (have three, one a racer), but my 89 Tenere often worries me. I will start carrying a spare coil, thanks to your hard work, and the advice of the others.


Regards,


Dr. G, self-proclaimed "World's # 1 motorcycle adventure sleeper," and now known as a "Cheap Bastard" because I wont pay for self-promotional adverts to sell my books - Mr. Google knows where they are.keepcalm

I dont understand, it was coil and old coil was good?

I purchased a new coil and adapter. The old coil tested good along with the adapter.

So the carb was the problem?

Oops sorry old coil tested good but changed the coil anyway and it started. What I did through this headache was checked spark good, changed plug, used starting fluid still no start. Checked all connections and checked stator, pickup coil, and coil all tested good. Now took off carb all good. What I did was order up coil because i felt there was spark but maybe was not enough to ignite to start. After all that checked valves. Still no start. Coil came in and installed and started. To make sure that was the problem I installed the old coil and again it did not start. Put the new one in started right up. I read some where that you need real good spark to get these 690 started so I tried that for 100 bucks oem it did take 4 weeks to get.

Congrats