VFRDiscussion ARCHIVE / READ-ONLYREAD-ONLY

Rear cam tensioner plunger

15 posts Started 4 Nov 2016 Last recovered post 31 Dec 2016 Wayback Machine snapshot 2 Jul 2017

#1

I was wondering if anyone could help me?  I just replaced my rear cam chain tensioner plunger (it was clicking!) and it was pretty straight forward.  Only problem was when I got the new one in, the bike wouldn't start.  It turns over and if I turn the throttle it tries but won't light off.  Is it possible the chain slipped or something similar that might be causing the timing to now be off?  I can't figure it out.  Everything seemed to go easily and smoothly.  I used the little tool to back the plunger out and hold it there while I took the old one out and then again when I put the new one in.  Any help would be appreciated.

Matt

#2

Everything plugged in? i.e rear cylinder coil packs

#3

The cam timing could only be off if the engine was turned over while the tensioner was removed or if not installed properly.  What all did you remove to get to the tensioner?

#4

I didn't unplug anything.  The only things I removed was the heat shield with the right foot peg bracket (had to in order to get at the plunger).  I did not run the motor until everything was buttoned back up again.  I left the bracket and shield off until I tried running the bike to see if it worked, and it did not.  The only thing I can think of is somehow the plunger hit the tensioner when the tool was removed and caused it to jump the chain?  I am truly mystified.  I appreciate the responses and help.  Though this was going to be easy!

#5

Where are the coil packs plugged in?  Could I have inadvertently unplugged them because I didn't unplug anything on purpose.

#6

The coil packs are on top of the plugs.   Each has a pigtail from the wiring harness attached to fire the coil.  If detached it's an easy fix.  

#7

I'll take a look but I don't think I did that.  I was only on the side down low as I was only doing the rear plunger.

#8

If you suspect that the cam timing is off, you'll need to remove the timing cover and the rear cam cover to check the timing marks.  You can download the FSM for free in the downloads section. 

#9

Ouch.  Seems like a lot of work.  What are the odds something like that happened?  I just can't imagine I did something to throw the chain off and thus the timing?!

#10

Before you panic, maybe it's something simple.

Is the kill switch turned on?

Is the battery fully charged?

Did you perhaps flood the engine while trying to start it?

Maybe hook up the bike to a car battery (car turned OFF) and try to start your bike that way.

Hold throttle fully open and crank for ~15 seconds to clear the cylinders if you think they're flooded (strong smell of raw fuel).

#11

Thanks.  I am working through that now.  It is just the oddest thing.  Take out a cam tensioner plunger - put in a new one and the motor doesn't start!  Kill switch is on.  Starter turns the motor and with full throttle it tries to stay running but never gets above 4-500 rpm and if I let the starter go or the throttle it dies.  It really makes me think it is something electrical.  Can't imagine I messed something up inside.  Who knows at this point.  Slow methodical process of elimination.  Appreciate all the input.

#12

It's happened to others that a service they performed just happened to coincide with a developing problem surfacing.   It's not a given they're related.  Checking the cam timing is not too big a deal - remove the right side fairing, timing cover plug and cam cover.  If you can swing the tank around to the rear you probably don't even need to disconnect it (unless close to empty siphon it to make it easier to handle).   Poor fuel delivery or a weak electrical system - even mice nesting in the aribox could cause / contribute to those symptoms.  Checking the cam timing would also allow you to verify that the chain tension is good ruling out that the tensioner is not working properly.  Good luck with it. 

#13

Thanks a lot for the input.  I will be digging into this over the coming weeks.  Kids preclude this being a quick fix!

#14

So Let us know how does the story end ?

What was the problem ? 

#15

Well it has been a while but... nothing has worked.  I have tried everything I can think of.

- Cam chain tensioner is back in.

- I did not remove anything else;  no wires, no hard parts, nothing.

- If I try to start the bike it turns over but won't light off.  If I use about 1/2-3/4 throttle it sounds like it wants to run but won't.

- I have checked the battery.  It is good to go.  I attempted to jump the bike from a "jump pack" to no avail.

- I checked the fuses in the front right fairing.  All are good (are there any others to check?)

- I removed the air filter and put fuel into the four intakes.  Turned the throttle and tried starting - nothing.  Didn't even sound any different than previous attempts.

- I hooked a timing light to one of the coil packs on top of the spark plugs.  Got a flashing light the first time and then nothing later.  Don't know if I was doing something wrong or if I should even be able to get a light.  I am not checking the timing, just trying to see if electricity is getting out there.

- I don't know what else to check.  The shop manual says the ecu could be bad? 

If anyone has any suggestions I would appreciate it.  It ran fine before I removed the cam chain tensioner plunger and afterwards it just won't start!  The actual starter (sequence) sounds normal (nice and healthy) it just doesn't light off.  I am about to have to take it in.


Thanks for all the replies so far.  Great group to be a part of.

Matt

End of thread · 15 posts recovered Wayback Machine snapshot 2 Jul 2017