Valve check problem

Auburn · Apr 13, 2019

Cross posting this from a thread started over on FJRiders.com

I did the valve check and discovered that the timing chain had slacked and skipped a tooth on the crank gear. Even though I had tye wrapped the chain before removing the cam chain tensioner.

(images borrowed from raYzerman)

I rechecked went through and reset the cams, all the marks line up, no slack in the chain on the exhaust side, chain is tight between the cams. Bike starts up easily, idles for about a minute. If I try to crack open the throttle, it dies. Restarts easily again.

My bike is set up with the following:
here are the valve numbers:

When I pulled the plugs they looked perfect. Nice clean, no build up, white in color. I also run a PC5 with auto tune (no changes to the settings). I add ring free with every tank. Bike was running fine when I parked it for the winter. Fuel had stabile added on the last tank before winter. Only have about 2 gallons left in tank, Bike has been stored on my bike lift all winter in the garage.

My bike is ridden 2 up about 95% of the time and has about 40,000 miles pulling a trailer. It has been worked hard, but not run at high RPM for extended periods of time.

Typically it is on the open road running about 4200 RPM in 5th.

I am going to go back in and recheck the valves clearances, check the timing marks all line up, do a compression test. If that all checks out then I will remove the PC5 from the equation.

After that I am at loss of what else to check. Any thoughts?

Auburn · Apr 13, 2019

I'm at a loss what to look for. Any ideas would be appreciated.
I went back in and checked the following:
Valves check out as shown on the valve sheet above.

Cam/crank timing are correct
Compression #1 190, #2 165, #3 192, #4 190 (Checked them twice, ran the starter until they stabilized for about 5 seconds before stopping, they were each up to pressure in about 4 cycles)
I also removed the PC5 form the system.

The bike starts easily, goes through the warm up cycle and starts to idle down after about 30 seconds. If I try to open the throttle, it dies. If I leave it idling, it dies after about a minute. It will restart again, but can't get it to go above an idle.

Ran the same way with the PC5 out of the system. Although it didn't start as easily.

I went back into check the timing again to make sure it was still correct and it is. While doing so an odd thing happened, when I unplug the fuel line to take the tank off, there is unusually high pressure on the fuel line. It gushes fuel when I separate the connector, normally you get just a little fuel, but this will soak a shop rag. This happened the other two times I removed the tank after the doing the first valve check.

The very first time I took the tank off, it was the normal few drops no crazy high pressure.
Is it possible I have a fuel injector(s) stuck open?

RossKean · Apr 13, 2019

Sounds like it isn't getting enough fuel. I am wondering if the pickup screen on the fuel pump is plugged or if fuel injectors are plugged. Seems to me that dcarver had a similar situation with plugged injectors...

Auburn · Apr 13, 2019

RossKean said:
Sounds like it isn't getting enough fuel. I am wondering if the pickup screen on the fuel pump is plugged or if fuel injectors are plugged. Seems to me that dcarver had a similar situation with plugged injectors...

I don't think the pick up screen is clogged. I'll check the injectors.

Never pulled any tank before and had this kind of pressure in the fuel line when separating the rubber hose before.

RossKean · Apr 13, 2019

This is what happened to Carver:

https://www.fjrforum.com/forum//index.php/topic/167438-2016-03-31-krzy8-running-rough-just-above-idle/?hl=injector

IIRC, you have a "Frankentank" on your bike. Just wondering if there is a possibility that body fill or residual crud from the manufacture eventually made it into your fuel system??

Not saying this is the issue but worth checking. The fuel pump is obviously producing enough pressure although pressure does not necessarily equate to flow if there is a restriction somewhere.

The only other thing that occurs to me is the connector for the "cylinder identification sensor" as referred to in the FSM (on the valve cover). For some reason, it is called a "speed sensor" in on-line parts fiches. Make sure it is hooked up. (Really the only electrical thing disconnected in a valve check other than the tank connections and PAIR stuff if you still have it.)

Edit: Also note my first response (Post #3) in dcarver's thread about an issue I had with a pinched wire to the O2 sensor on my bike. Not likely related but a quick check.

Edit again: I originally looked at this post (and replied) via my phone. Just looked at the original photos on a big screen. I assume that isn't a picture of your engine in the first pic? (Engine out of bike and cam sprockets don't line up.)

Auburn · Apr 13, 2019

RossKean said:
This is what happened to Carver:
https://www.fjrforum.com/forum//index.php/topic/167438-2016-03-31-krzy8-running-rough-just-above-idle/?hl=injector

IIRC, you have a "Frankentank" on your bike. Just wondering if there is a possibility that body fill or residual crud from the manufacture eventually made it into your fuel system??

Not saying this is the issue but worth checking. The fuel pump is obviously producing enough pressure although pressure does not necessarily equate to flow if there is a restriction somewhere.

The only other thing that occurs to me is the connector for the "cylinder identification sensor" as referred to in the FSM (on the valve cover). For some reason, it is called a "speed sensor" in on-line parts fiches. Make sure it is hooked up. (Really the only electrical thing disconnected in a valve check other than the tank connections and PAIR stuff if you still have it.)

Edit: Also note my first response (Post #3) in dcarver's thread about an issue I had with a pinched wire to the O2 sensor on my bike. Not likely related but a quick check.

Edit again: I originally looked at this post (and replied) via my phone. Just looked at the original photos on a big screen. I assume that isn't a picture of your engine in the first pic? (Engine out of bike and cam sprockets don't line up.)

the cam sensor (speed sensor) is connected. I don't believe the bike would start without it.

02 sensor is the wide band one for the auto tune. wires are all good.

The picture is raYzermans showing how the timing marks should look for the cams.

will check the tank and injectors today.

rushes · Apr 13, 2019

Just a random thought, you might check for a rodent nest in the airbox...

RossKean · Apr 13, 2019

I assume that there are no stored codes in the diagnostic?

Auburn · Apr 13, 2019

rushes said:
Just a random thought, you might check for a rodent nest in the airbox...

No nest, clean air box and filter

RossKean said:
I assume that there are no stored codes in the diagnostic?

No codes

ogopogo · Apr 13, 2019

Throttle sensor issue?

Auburn · Apr 13, 2019

ogopogo said:
Throttle sensor issue?

Nope checked that on the diagnostic, was in spec.

I went through and emptied the fuel tank, pulled the fuel pump assembly, everything looked good, no crud in the tank. Checked all the connectors, ran through the diagnostics, had the computer test each injector (diag 36, 37, 38, 39 then turn the kill switch off and then back on - fires each injector 5 times and you can hear the click audibly each time.) Used the diagnostic test to check and test all sensors, and other devices that it can do. All checked out. I had no codes being thrown before I started either.

put in new fuel about 3 gallons. put her all back together. Fired right up, revved like normal. Let it run for about 5 minutes enough to get 4 bars on the temp gauge. Now I'm letting it sit to draw antifreeze out of the overflow bottle to ensure the system is full.

I'll do a throttle body synch after it cools off in a couple of hours.

Not sure if it was fuel being old, not enough, or a connector not fully seated. I didn't find any particles in the fuel when I dumped it out into a clean oil catch pan. But you never know.

Thanks for everyones ideas.

samamoto · Apr 13, 2019

Edit: As I was writing these you posted that you solved the issue.

RossKean · Apr 13, 2019

Hopefully it was just fuel or a connection you "fixed" with the work you have been doing...

Plugged fuel injectors will still fire through the diagnostics. Can't tell if one (or more) is plugged without removing them.

Auburn · Apr 13, 2019

RossKean said:
Hopefully it was just fuel or a connection you "fixed" with the work you have been doing...Plugged fuel injectors will still fire through the diagnostics. Can't tell if one (or more) is plugged without removing them.

Yep. I'll keep track of it. I did do a throttle body synch with the 3500 rpm as my point that I wanted them spot on. at idle they vary less than one mark on the scale. At 3500 they are perfectly straight and don't vary at all. Nice and smooth.

I think it was just old fuel that had ethanol in it. The new fuel is ethanol free. I started it several times today to check, sounds very smooth, revs nicely, very snappy off idle.

JamesW · Apr 14, 2019

AuburnFJR said:
RossKean said:

Hopefully it was just fuel or a connection you "fixed" with the work you have been doing...Plugged fuel injectors will still fire through the diagnostics. Can't tell if one (or more) is plugged without removing them.

Click to expand...

Yep. I'll keep track of it. I did do a throttle body synch with the 3500 rpm as my point that I wanted them spot on. at idle they vary less than one mark on the scale. At 3500 they are perfectly straight and don't vary at all. Nice and smooth.

I think it was just old fuel that had ethanol in it. The new fuel is ethanol free. I started it several times today to check, sounds very smooth, revs nicely, very snappy off idle.

Amen.

dcarver · Apr 14, 2019

Interesting read. Hate it when there isn't a definitive smoking gun. If you need I have fresh refurbished injectors sitting in a box. Sounds like you are good to go though... Very thorough testing, congrats. And now I'm scared to lift Naomi's cams...

Auburn · Apr 15, 2019

dcarver said:
Interesting read. Hate it when there isn't a definitive smoking gun. If you need I have fresh refurbished injectors sitting in a box. Sounds like you are good to go though... Very thorough testing, congrats. And now I'm scared to lift Naomi's cams...

You can do it. IF you have an impact driver, (after you have #1 cylinder at TDC on the compression stroke - cams facing out) then remove the crank sensor so you can mark the chain and the gear to make sure it doesn't move. That is what I had to do verify the timing with no slack between the crank gear and the exhaust cam.

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