K75 Starting Issues.. Fuel Pump priming?

[rbm]

So the latest installment... still not starting...
We took out the Injectors and watched the spray pattern/volocity - looks weak to us, mild squirting going on but nothing to compare it too except a Video on Youtbe, but all three are squirting fuel. We've ordered a Manometer to measure Fuel Pressure and Drop.

The injector spray pattern should be strong, not weak.  If you are uncertain of the supplied fuel pressure, then the resulting pattern could be caused by (1) dirty/stuck injectors or (2) low pressure.  Can you find a local diesel repair shop who could refurbish the injectors?

Sparks wise we had nothing again, went back to the troubleshooting bible and measured a low voltage on Pin 2 of the ICU - the Hall sensor Feed - not 12v, more like 11v dropping to 8v when cranking which would point to issues energizing the Coils and wiring problems
So we fashioned a direct permanent 12v direct to the Hall Sensor plug - 2/3 sparks came back.

How did you measure the voltage drop across the HES?  Was it using a digital voltmeter?  Was the voltmeter set to AC Volts or DC volts?  I think your diagnosis process is flawed.  It doesn't truely tell you the condition of the HES since the DCV setting is not responding fast enough and the ACV setting would show you the true RMS value of the resulting output.  You'll have to use an oscilloscope or LED to test the HES.

Can anyone confirm the Fuel Pump Pressure on a K75 for when we get the Meter?
K100 Guide says 65 PSI from Pump dropping to 35 PSI at the regulator - is this the same for the K75?

Yes, those pressures are also applicable to the K75.

[bluebossa]

The injector spray pattern should be strong, not weak.  If you are uncertain of the supplied fuel pressure, then the resulting pattern could be caused by (1) dirty/stuck injectors or (2) low pressure.  Can you find a local diesel repair shop who could refurbish the injectors?


>> Thanks RBM - The Injectors have been out and sonic Cleaned in the last couple of weeks... Pressure gauge / Manometer on order for proper pressure measurement.

How did you measure the voltage drop across the HES?  Was it using a digital voltmeter?  Was the voltmeter set to AC Volts or DC volts?  I think your diagnosis process is flawed.  It doesn't truely tell you the condition of the HES since the DCV setting is not responding fast enough and the ACV setting would show you the true RMS value of the resulting output.  You'll have to use an oscilloscope or LED to test the HES.


>> The Voltage I am referring too is from the Troubleshooting guide and is the energizing voltage rather than the operational RMS Values. i.e. it should be 12V static on Ignition on. When we crank it reads down to 8V DC not AC, we don't have an oscilliscope.

Yes, those pressures are also applicable to the K75.


>> Thanks

[bluebossa]

The fuel pressure is correct.
Did you do the dark room crank looking for sparking wires? 2/3 plugs is pointing to your ignition system.

Hi Laitch when you say Fuel pressure is correct, do you mean the 65 and 35 PSI I quote are correct for the K75?


Re Dark Room test - yep we turned the lights off today as you suggested, no stray sparks, arcing witnessed.
If it's pointing to our ignition system - to which part is it pointing?

[rbm]

The Voltage I am referring too is from the Troubleshooting guide and is the energizing voltage rather than the operational RMS Values. i.e. it should be 12V static on Ignition on. When we crank it reads down to 8V DC not AC, we don't have an oscilliscope.

Ok, got it.  I just assumed that you were measuring the output of the HES but you're measuring the supply voltage to the HES.  And you're seeing a substantial drop in the supply voltage during cranking (some reduction in supply voltage during cranking is to be expected but not 4 volts).  Can you also measure the terminal voltage drop during cranking at the battery?  If it also is 4 volts or theres about, the CCA capacity of the battery may be insufficient.


Is it possible to eliminate one unknown factor from your testing -- the LiPo battery.  Can you remove the LiFePo battery and test with a regular lead acid instead, maybe even a spare car battery temporarily hooked up with jumpers?  You can't say for sure whether the LiFePo battery you've been using is sufficiently sized in CCA to not cause these problems.

[Laitch]

Hi Laitch when you say Fuel pressure is correct, do you mean the 65 and 35 PSI I quote are correct for the K75?
Re Dark Room test - yep we turned the lights off today as you suggested, no stray sparks, arcing witnessed.
If it's pointing to our ignition system - to which part is it pointing?

Yes that's what I meant and that's what rbm indicated also.
The condition of only two out of three spark plugs igniting points me to the ignition system.

[Laitch]

Saw an online video about squirting 10ml of Oil into Each Cylinder - to get it too start, but not tried this...?
Anyone one know if this is real - Engine Oil?

If you mean were you watching a video with special effects and that no motor oil was used, no. It was real. The technique can restore compression in an engine that has been idle for months or years. Restored compression helps the fuel ignite. It's difficult to get any engine started when enough fuel might not be getting to the cylinders and only two out of three spark plugs are firing as you have indicated is the condition of your bike's engine.

[bizzaro]

Pardon me, have you checked the cylinder compression?  (Not that poor compression can be the result of only two plugs firing, or vice versa, etc. etc.  but if compression is not high enough, no amount of gas, or spark will start an engine)( I think that is what the reference to squirting oil in the cylinders was, to raise compression in the cylinder)  It would seem to me, if you have some good spark, and some fuel, GOOD FUEL,( I mean your in Dubai  :hehehe ), and have good compression, it should at least belch and fart on occasion when you attempt to start it? And I haven't seen where you have confirmed you have good flow of gas to the FPR? 

Damn. Once again Laitch has beaten me to the punch!  I throw in the towel!! :falldown:
I need to learn to compose faster and more concisely...................I rewrite everything a dozen timessssss! :musicboohoo:

[bizzaro]

Sure would be nice for the folks who took the time to respond to this thread know what your conclusion was bluebossa? Hello?????? :nono Even if you "gave up"?  I would like to know?? 

[bluebossa]

So - we got  back onto the K75 - we kept on fiddling.... then Boom, we discovered the issue and got it running...
We only got it running this last week so apologies for the delay, but we lost interest in it for a few weeks after all the troubleshooting and time we'd put in...



After following everything on this thread, and more plus following the troubleshooting guide it turned out to be>

A FAULTY IGNITION SWITCH - HIGH RESISTANCE ON THE INTERNALS


Here's what we did. After checking again basic Top Dead Centre, Timing Hall Sensor position and Fuel Pressure with a Manometer.


[/size]We reverted to the Old Clocks and noticed that fully charged and connected the Ignition lights were weak?


As we'd taken the ignition switch off from it's modified position on the tank, we were holding this away from the Bike in order to turn it on... My brother noticed that a slight bend of the Ignition wires brought the Dash lights back to Full strength?


So while pushing on the rear of the Ignition barrel - we cranked it up.
Boom - It sprung into life... We couldn't believe it...!!


We noticed that one of the Connections of 3 on the switch was taking all the Amps - RED HOT to the Touch... i.e. it was draining all the current to the entire Electronics...


We dismantled the entire Ignition switch - which was the original unit, cleaned everything out, and put everything back together...


A quick tweak of the Timing and it's up and running....


I'll re-read the troubleshooting guide, but I think I'm right in saying nothing is mentioned about checking the Ignition switch - we spent hours, cleaning connections, earths, suspecting it was Voltage related but didn't come across this until a fresh pair of eyes appeared...


Thanks to everyone who helped and I hope this helps others!!
In short nothing wrong with any ECU, ICU, Injectors, Sensors, Fuel Pump, Fuel Pressure, Relays, Fuses, Earths, Battery, Connections, Cables, Throttle Position Sensor, Temperature Sensor etc etc etc...


Never mind - very frustrating but ultimately back in action... just before we set fire to it... !

[The Mighty Gryphon]

By ignition switch, do you mean the key switch?  They are notorious or causing trouble, but normally it prevents the entire electrical system from turning on.  The starter will not run. 

Since it appeared that you were able to crank the engine we did not think the switch was behind your problem.  In any event, congratulations on getting your bike running. :clap:

[Laitch]

Thanks for the update.  :clap:

[bluebossa]

Yeah, Ignition Switch = Key Switch, that's what we call em in Blighty...


It threw us off the trail too, the Bike always cranked and turned over and the new Digital Speedo lit up so we didn't investigate it whatsoever...


We never suspected it because it apparently was doing what it should - i.e. Turn the Bike on!
It was only when we sensed the heat being built up that we realized what a high resistance it was presenting...


Guessing this was dropping the Power - reducing it to the ECU / ICU and causing the weak sparks we had witnessed.
We'd even taken the Starter off and cleaned that as we always suspected power issues...

[bluebossa]

Thanks for the update.  :clap:

You're welcome - we put the tools down for a few weeks, my Brother flew out to Dubai, so we gave it another look and he spotted it...


Moral of the Story - beyond Earthing, check the Ignition switch out... for heat and resistance...

[The Mighty Gryphon]

Thanks for the update!  Putting information into the data bank.