Won't start after valve adj

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Spark, fuel, compression.

If you have fuel running through the system you should be able to smell it coming out the exhaust while you are turning the starter.

You can check for spark by removing a plug, leave the wire on it amd hold the base of the plug against the metal engine while you turn the atrter. You should see a spark at the tip of the plug. Use a well insulated tool to hold the plug or you'll get a shock up your arm. Of course that would verify that tyou have spark as well as watching the plug tip.

That leaves compression. If you are sure that you didn't damage a valve, and you know that your cam chain timing is right, and your shims are correct, then it is not likely to be a compression problem.

My guess would be no spark due to a flooded engine. Remove the plugs, dry them, allow the engine to air out overnight with the plugs out while you fully charge the battery, If it doesn't start right up, then try the WOT technique described in several threads on this forum.

 
Spark, fuel, compression. ...You can check for spark by removing a plug, leave the wire on it amd hold the base of the plug against the metal engine while you turn the atrter. You should see a spark at the tip of the plug. Use a well insulated tool to hold the plug or you'll get a shock up your arm. Of course that would verify that tyou have spark as well as watching the plug tip...My guess would be no spark due to a flooded engine...
Geezer has the basics, the only curveball is that having mechanically mis-timed the engine (the cam chain uh-oh) other things could be at play here too. A quick compression test will show if there are mechanical problems like mechanical cam timing still wrong or other Bad Things.

As far as firing the sparkplugs, use The Force, let the power of diAG codes 30 & 31 show you the way... No need to mess with those cold, hard, knuckle busting tools. If you go to the diAG screen and sequence up to diAG code #30 then turn the red run/stop switch off and back on again plugs #1 & #4 will fire 5 times; at code #31 plugs #2 & #3 will fire 5 times. I can hear the plugs fire without having to remove anything, they make a strong popping noise. Codes 30 & 31 are intended to let a mechanic use a plug simulator to check for spark but it will work the same way with a standard plug too. Using the diAG codes you can fire any plug without having to crank the engine.

If you try the codes and don't hear anything then it is time to actually pull plugs and check for a fat blue spark. Weak yellow or red spark is no good, the spark must be blue/white.

Coil #1 fires plugs #1 & #4 at the same time; coil #2 fires plugs #2 & #3 at the same time. If anything is wrong with Coil 1 or Coil 2 usually both plugs associated with that coil will fail to fire.

 
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Geezer has the basics, the only curveball is that having mechanically mis-timed the engine (the cam chain uh-oh) other things could be at play here too. A quick compression test will show if there are mechanical problems like mechanical cam timing still wrong or other Bad Things™.
As far as firing the sparkplugs, use The Force, let the power of diAG codes 30 & 31 show you the way... No need to mess with those cold, hard, knuckle busting tools. If you go to the diAG screen and sequence up to diAG code #30 then turn the red run/stop switch off and back on again plugs #1 & #4 will fire 5 times; at code #31 plugs #2 & #3 will fire 5 times. I can hear the plugs fire without having to remove anything, they make a strong popping noise. Codes 30 & 31 are intended to let a mechanic use a plug simulator to check for spark but it will work the same way with a standard plug too. Using the diAG codes you can fire any plug without having to crank the engine.

If you try the codes and don't hear anything then it is time to actually pull plugs and check for a fat blue spark. Weak yellow or red spark is no good, the spark must be blue/white.

Coil #1 fires plugs #1 & #4 at the same time; coil #2 fires plugs #2 & #3 at the same time. If anything is wrong with Coil 1 or Coil 2 usually both plugs associated with that coil will fail to fire.
ionbeam, that's awesome...

& that folks may be the single most informative post I've read on this forum in a LONG time.

 
& that folks may be the single most informative post I've read on this forum in a LONG time.

I agree; thanks for that ionbeam/ :thumbsupsmiley:

(no I am never adjusting my valves myself but my bike has suffered from "won't start" syndrome and this will be great diag tool <_< )

 
Here's the latest scoop. zero compression in cyls 1, 2, 4. 50 lbs in #3. I take off the valve cover and the cams are still perfect. I then notice that some of the valves don't close all the way. It seems that both intake valves in 1, 2, & 4 are likely bent and don't close. Are the valves really that soft that I can bend them when cranking by hand?

Now that I've gotten it apart to the valves, it looks like it's not much more to pull the heads and take them to the shop for a complete valve job. Is it really that easy?

It says in the book to remove the radiator, exhaust, & I imagine the throttlebodies.

Or should I just tough it out & trailer the thing to the shop & let them do it all? :eek:

 
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Well shit Keith, this is gonna suck no matter what. Do you have a dealer that you absolutely trust, that has (successfuly) done this kind of work on a FJR before, that will warranty his work, and will stick with you and 'do the right thing' should it not go as well as expected? And, are you ready to pay >$2k? Then again, if you strike out on your own you are on the hook for all the cost, no support if there are problems, no Yamaha technical help and you are porked if the job doesn't go well and you have to pull it all apart again. There is a massive parts list of gaskets, seals plus all the little bits and pieces that are needed when the cylinder heads come off.

If you spun the motor with the starter, the mechanical advantage of the pistons will definitely bend the valves with no effort at all. You won't even have time to THINK 'oh shit' before the damage is done.

In my case, the cylinder head was trashed around a couple of valve guide castings so it didn't matter that there was one cyl head bolt that wouldn't come out and the head got damaged while removing the bolt.

Yamaha told my dealer that if there was enough force to bend almost all the valves that the crank needs to be pulled and to check the crank, plane bearings, rods and pistons. In my case there was no damage but there were stuck piston rings on 3 cylinders. The cam chain gear on the crank shaft is pressed on so the whole crank assembly has to be replaced if this gear is damaged. There are no FSM specifications for this gear, my shop had to have a Yamaha tech come out and measure the gear to determine its health. Your lower reciprocating components are probably fine. Do ya feel lucky and want to ignore all these parts?

My dealer, who has done this kind of work before put my engine back together just like every other engine, and did it all by the book. My engine ran like shit. My dealer 'did the right thing' and pulled my engine a second time at his cost. He had to have a Yamaha tech resolve the problem because they couldn't find it on their own. Even though they had aligned all the parts by the dimples, case seams and arrows per the Technical Addendum and FSM they still got it wrong. It seems that there are many parts that have secondary dimples 120° apart that none of the manuals mention. Once aligned with the Yamaha tech's help all is well. It only took them 6 months from beginning to end (January to June) to get it all done right. My bike is running well right now. My wife and I did ~2.5k miles in 6 days going to/from EOM and our FJR ran like a fine Swiss watch.

I can't tell you what to do, but I can supply some real life experience. If you didn't read my link in post #2, now is the time.

If we ever meet we can cry together over a couple o' drinks and tell horror stories about crushed valves. I feel for ya man!

 
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What an experience, Ion! I suspect the bottom end is fine because I never got the motor into a bind using the starter or while it was actually running. It either bent while I was turning the crank by hand, or by partially tightening the cam bolts while the cam was not lined up proper. I didn't actually tighten them completely down, but it was far enough to feel something wasn't right.

Given that, I'm thinking about taking the heads off and having them bench fixed. Unless, of course, this involves a lot more than the manual states. Is there enough room to remove the heads without dropping the motor?

 
The cylinder head can come off with the engine still in the frame.

I never had an indication of binding or any other catastrophic noises (until my screaming after seeing 0 psi of compression).

Best of luck!

 
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The motor has to come out to get the head off.
I never had an indication of binding or any other catastrophic noises (until my screaming after seeing 0 psi of compression).

Best of luck!
I wasn't there to witness it but when the tick was fixed on my 03 the head was removed with the engine in place. When I stopped by to check on it the head was on the bench and the rest was still in the bike. The tech said there is just enough room if you are carefull.

 
I wasn't there to witness it but when the tick was fixed on my 03 the head was removed with the engine in place. When I stopped by to check on it the head was on the bench and the rest was still in the bike. The tech said there is just enough room if you are carefull.
That's the difference between a guy who can beat flat rate and a guy who can't.

 
Here's the latest scoop. zero compression in cyls 1, 2, 4. 50 lbs in #3. I take off the valve cover and the cams are still perfect. I then notice that some of the valves don't close all the way. It seems that both intake valves in 1, 2, & 4 are likely bent and don't close. Are the valves really that soft that I can bend them when cranking by hand?
Now that I've gotten it apart to the valves, it looks like it's not much more to pull the heads and take them to the shop for a complete valve job. Is it really that easy?

It says in the book to remove the radiator, exhaust, & I imagine the throttlebodies.

Or should I just tough it out & trailer the thing to the shop & let them do it all? :eek:
Really sorry to hear about the valve crash, Keith. About the one and only positive is that at least you did this going into winter, rather than coming into spring.

:(

 
Thanks, guys. It looks like I have my winter project. :lol: I've already lined up a mechanic to benchfix the head at a reasonable cost. I won't take it to the nearest dealer (where I bought the bike) because the head mechanic has an attitude about do-it-yourselfers and I don't care to hear him get snotty.... :angry:

 
Many are the cases (concerning modern m/cycles) that, while 'possible', it's often better (if not actually faster) to R&R the engine assembly when performing extensive repairs on major engine components.

I remember well when I started seeing with increased frequency in shop manuals: "Remove the engine...". :(

Mechanics do find shortcuts, tho -- but, most of these serious things are probably not good candidates for those.... :eek: :huh:

 
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The head is off. It wasn't too bad and went pretty much just as the manual said. The head comes out to the front and took about 2 hours. Just as I thought, you can see the 6 intake valves very bent.

Nov252008007s.jpg


For only 24,000 miles, the pistons look like they are a little gunked up. So much for gasahol keeping the innards cleaner.

Nov252008009s.jpg


Off to the bench for new valves and some minor porting.

 
Oh man, Keith -- very sorry to hear that this was the result. While you're getting a complete valve job, you might want to consider having the exhaust valve guides replaced with the newer spec that is used for the tick fix. I'm assuming yours was never a ticker, but on the possibility that it could still develop later, maybe an ounce of prevention?

 
Man that sucks. In a nutshell, what went wrong? I know I'll need to adjust my valve clearances one day and I definately don't want to repeat this horror show. I guess its because you didn't have the camshafts aligned properly on the cam chain before trying to start the engine or because you tried to rotate the engine the wrong direction with the wrench.

 
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