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Crankcase filling with fuel

3217 Views 22 Replies 6 Participants Last post by  mpp12
Edit: Faulty PC3 was the culprit.

Recently my case has been filling with fuel on my 2005 10r with only 30000km. I thought it was the power commander so I took that out of the equation but it's still happening. I'm definitely going to pull the injectors and get them serviced but I was wondering if anyone else has had this similar problem and was it the injector(s) or electrical.

Thanks
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I'm pretty sure you can't service your injectors. Just an additive in your gas. I ran into the same problem with my 04 z10r
I changed oil filter ( used a cheap oil ran couple min then dumped that and refilled with proper oil. Any way it turned out to be a dead plug , or weak plug. Changed plugs ( that was a time consuming job so do it yourself cuz labour cost )
Also I stopped using a really high octane gas and I'm just running Reg 87% octane unless I race then I'll use a high test but really not much of difference in power my bike seems to run better and cooler with Reg gas


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Always look at the simple things first


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I'm pretty sure you can't service your injectors. Just an additive in your gas. I ran into the same problem with my 04 z10r
I changed oil filter ( used a cheap oil ran couple min then dumped that and refilled with proper oil. Any way it turned out to be a dead plug , or weak plug. Changed plugs ( that was a time consuming job so do it yourself cuz labour cost )
Also I stopped using a really high octane gas and I'm just running Reg 87% octane unless I race then I'll use a high test but really not much of difference in power my bike seems to run better and cooler with Reg gas


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By servicing I mean sonic cleaned and flow tested, that will let me know the condition and if I need to look elsewhere.

I just checked the plugs when I did a VC gasket and all looked proper with the same pattern.

I have motor work done and higher compression so I have to use premium as that's what it's tuned for.

Thanks for the advise.


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Ive also also had work done on my z10 and run higher compression , and was told I should run the highest octane I can find , so I ran 94 -96 when I can find it. ( Ont canada)
I also have a power commander fuel injection module All I'm saying is when I run a higher premium gas , it runs really lean and hot
I thought about shit caning the module after remapping and no effective change but before I did that I dumped the premium into my truck and refuels with regular gas and my race time stayed the same 9.46 @ 144 mph the bike is just as fast but runs way cooler.
I hope your gas in oil problem is a simple thing and not major , mine was a bad plug All the best to you friend :)


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Ive also also had work done on my z10 and run higher compression , and was told I should run the highest octane I can find , so I ran 94 -96 when I can find it. ( Ont canada)
I also have a power commander fuel injection module All I'm saying is when I run a higher premium gas , it runs really lean and hot
I thought about shit caning the module after remapping and no effective change but before I did that I dumped the premium into my truck and refuels with regular gas and my race time stayed the same 9.46 @ 144 mph the bike is just as fast but runs way cooler.
I hope your gas in oil problem is a simple thing and not major , mine was a bad plug All the best to you friend :)


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Really eh? Mine runs lean up top and gets hot as well. Ok well I'll try dropping the octane to 89 instead 93 and see if there's a difference. I'm in Ont as well.

Thanks man


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I don't have a lot of experience with Kawi's in this regard, but on the Honda's we always check the Fuel Pressure Regulator when things like this happen. When they go bad they can slowly drain fuel into the cylinders at rest and it seeps past the rings and can also cause fouled plugs during start-up as well. In really bad cases it can literally fill the cylinders with fuel and hydrolock upon cranking which usually results in bent rods.
That is something to definitely look at ...good call


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I don't have a lot of experience with Kawi's in this regard, but on the Honda's we always check the Fuel Pressure Regulator when things like this happen. When they go bad they can slowly drain fuel into the cylinders at rest and it seeps past the rings and can also cause fouled plugs during start-up as well. In really bad cases it can literally fill the cylinders with fuel and hydrolock upon cranking which usually results in bent rods.

The only way fuel can enter the engine is through the injectors as they are the end of the chain. With my system the residual pressure would bleed off into the cylinder if a injector was stuck open. I should know tomorrow after flow testing is done if I need to dig deeper.


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The only way fuel can enter the engine is through the injectors as they are the end of the chain. With my system the residual pressure would bleed off into the cylinder if a injector was stuck open. I should know tomorrow after flow testing is done if I need to dig deeper.


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This is absolutely correct. It is not uncommon for old or dirty injectors to develop internal leaks that can cause this.... it's basically debris or deposits that keep the solenoid from completely closing, and siphoning effect can drain quite a bit of fuel into the cylinder(s) if there is no check valve for low-pressure flow. What's interesting to note about our bikes is that there is really no residual pressure OR low flow check valve in the system.... the pump has neither and the FPR is a 'venting' style set-up that is not in direct line with the fuel delivery (It just T's into the system and vents anything more than 43psi back to the tank).

In theory, if the injector is functioning properly it can hold an obscene amount of pressure for any period of time without issue..... too much pressure will actually prevent the injector from opening, not cause it to leak.... but we're talking well over 150psi in most cases there. If the FRP sticks closed the bike will flood on startup and not run.... if it fails open it will go lean the second you put any load on it and barely get off the kickstand.... they are really simple devices in our pump assemblies.
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Interesting, that is good info thank you , think I'm going to have my injectors Flow tested as well


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The only way fuel can enter the engine is through the injectors as they are the end of the chain. With my system the residual pressure would bleed off into the cylinder if a injector was stuck open. I should know tomorrow after flow testing is done if I need to dig deeper.


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On the Honda the Fuel Pressure Regulator is controlled by a vacuum line(s) that leads back to the throttle bodies. When the diaphragm fails fuel is allowed to travel that vacuum line and enter the cylinder completely bypassing the injectors.

Just for my own knowledge how does the Kawi control the FPR?
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On the Honda the Fuel Pressure Regulator is controlled by a vacuum line(s) that leads back to the throttle bodies. When the diaphragm fails fuel is allowed to travel that vacuum line and enter the cylinder completely bypassing the injectors.

Just for my own knowledge how does the Kawi control the FPR?


On my 05 the the regulator is in tank with the pump. Pressure is set at 44psi and will hold residual for 30sec then start to bleed off.
My injectors tested perfectly so time to start digging, lol.

Great advice and info guys!


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On the Honda the Fuel Pressure Regulator is controlled by a vacuum line(s) that leads back to the throttle bodies. When the diaphragm fails fuel is allowed to travel that vacuum line and enter the cylinder completely bypassing the injectors.

Just for my own knowledge how does the Kawi control the FPR?
That's good info! I've never seen a vacuum referenced FPR on a modern motorcycle... just goes to show how many different ways there are to skin a cat! I've seen what you describe on cars fairly often (recently did one on an Evo 8, actually), but didn't think about it on a bike.

All the ZX pumps I've had apart (10R, 6R, 14R, C14, etc) use a spring controlled bypass circuit to bleed off any excess pressure past whatever the spring is, uhm, sprung. :) They make it a removable part of the fuel pump assembly... usually a metal piece roughly as big around as a quarter and about an inch long that T's into the supply side of the housing after the filter element... and it just bleeds right back into the tank that way. A common mod to get a little more fuel pressure is to 'crush' them slightly to increase the vent pressure threshold. In this system the only thing that holds fuel pressure once it's turned off is the pump. Some pumps have internal check valves, but most simply bleed down slowly until they equalize.
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On my 05 the the regulator is in tank with the pump. Pressure is set at 44psi and will hold residual for 30sec then start to bleed off.
My injectors tested perfectly so time to start digging, lol.

Great advice and info guys!


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Just a thought: are you doing a lot of short rides or warm-ups without really riding it for long periods? Fuel past the rings is natural on start-up, but getting the oil up past 190F for a good period of time is usually enough time to evaporate it from the crankcase. People who do lots of short rides or 'warm-ups' without really riding it for a good distance have this problem. Just getting it up to operating temp is not enough... the oil has to get all the way up and stay there for a bit to get most of the moisture and fuel 'burnt' out of it.

You seem like you know your stuff, but best not to assume. :)
Oh! I doubt this is the case based on your performance modifications, but does the bike still have any of the emissions equipment or tubing still installed... that can do some evil stuff if there is malfunction.....
Just a thought: are you doing a lot of short rides or warm-ups without really riding it for long periods? Fuel past the rings is natural on start-up, but getting the oil up past 190F for a good period of time is usually enough time to evaporate it from the crankcase. People who do lots of short rides or 'warm-ups' without really riding it for a good distance have this problem. Just getting it up to operating temp is not enough... the oil has to get all the way up and stay there for a bit to get most of the moisture and fuel 'burnt' out of it.

You seem like you know your stuff, but best not to assume. :)


All the short rides I jump in the cage, lol. 30sec after startup I'm gone and all my bike rides are 100km+ and hard, I don't use it as a commuter one bit. All the emissions stuff is gonzo and blocked off.

I try not to assume but it happens from time to time, lol. Thanks for the input, appreciate it.


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I tested the injectors with and without the PC3 and it turns out it actually was the PC3 triggering the injectors. There must have been residual fuel in the case causing the ticking because when I changed the oil the ticking went away everything is back to normal. 2 bad PC3 in two years, geez.

Thanks for all the help and info guys.


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Another pc3 bites the dust, I hope it didn't wipe out your rings.
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