Author Topic: Fuel in engine oil  (Read 9248 times)

Offline Soggz

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Fuel in engine oil
« on: March 13, 2019, 05:54:05 PM »
Ok.
Got the bike running pretty well.
Idle is still a bit strange on start up,need to rev it to keep it going until it's warm....but....
I have noticed the oil level has got higher.
Drained the oil to find that it's got petrol in it.
When I first got the bike, I gave it a little service, as in, oil,filter,,etc,then went about trying to get it to run properly. Had the injectors cleaned,new temp sensor,etc,now I have discovered fuel in the 'new' oil. Could this have been down to the dirty injectors before the clean,as to be honest,I never thought about checking oil levels until yesterday when I discovered the problem.
Thanks in advance.
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Offline Martin

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Re: Fuel in engine oil
« Reply #1 on: March 13, 2019, 06:00:40 PM »
Check the vacuum hose from the FPR for signs of fuel.
Regards Martin.
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Offline Soggz

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Re: Fuel in engine oil
« Reply #2 on: March 13, 2019, 06:28:16 PM »
Check the vacuum hose from the FPR for signs of fuel.
Regards Martin.
the smaller of the 3 hoses going into the throttle bodies, Martin?
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Offline Martin

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Re: Fuel in engine oil
« Reply #3 on: March 13, 2019, 06:35:15 PM »
The first two vacuum outlets have rubber blanking caps the last one near the TPR has a hose that supplies vacuum to the FPR.
* Fuelpressureregulator.jpg (14.55 kB . 295x379 - viewed 447 times)
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Offline Soggz

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Re: Fuel in engine oil
« Reply #4 on: March 13, 2019, 06:48:08 PM »
The first two vacuum outlets have rubber blanking caps the last one near the TPR has a hose that supplies vacuum to the FPR.
* Fuelpressureregulator.jpg (14.55 kB . 295x379 - viewed 447 times)
Thanks Martin.
Can that ' backfire' fuel back into the system via the to inlet? Not sure of these engines. Do I look for fuel traces, I.e,wet? in the pipe? What would cause this,if so? Dodgy regulator?
Thanks in advance.
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Offline Soggz

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Re: Fuel in engine oil
« Reply #5 on: March 13, 2019, 06:52:09 PM »
Ah,I see.
Could be perished or blocked diaphragm rubber,maybe?
It was sat for 16 years,before I bought it...
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Offline Martin

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Re: Fuel in engine oil
« Reply #6 on: March 13, 2019, 09:07:11 PM »
You can try putting a large syringe on the hose and draw it back. I don't recommend sucking on it, but it's your choice. If the leak is bad you will see it dribbling or spurting out of the hose when running.
Regards Martin.
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Offline daveson

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Re: Fuel in engine oil
« Reply #7 on: March 14, 2019, 01:31:06 AM »
While you had a serious overfueling problem, some of it would have got past the rings.
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Offline Soggz

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Re: Fuel in engine oil
« Reply #8 on: March 14, 2019, 03:47:08 AM »
You can try putting a large syringe on the hose and draw it back. I don't recommend sucking on it, but it's your choice. If the leak is bad you will see it dribbling or spurting out of the hose when running.
Regards Martin.
I have had the pipe off when it was running before, but never noticed fuel from it, I will look this morning.
Thank you.
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Offline Soggz

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Re: Fuel in engine oil
« Reply #9 on: March 14, 2019, 03:49:53 AM »
While you had a serious overfueling problem, some of it would have got past the rings.
This is true. The injectors have been sorted now, and I have a new thermo sensor in the bike now, so it may be cured(?),as the computer should be getting the right temp reading and not sending in more fuel, maybe?

I am slowly learning about FI.

Thanks.
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Offline Soggz

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Re: Fuel in engine oil
« Reply #10 on: March 14, 2019, 05:49:33 AM »
You can try putting a large syringe on the hose and draw it back. I don't recommend sucking on it, but it's your choice. If the leak is bad you will see it dribbling or spurting out of the hose when running.
Regards Martin.
Hi Martin, no syringe, but I got the bike running, and sucked on the pipe. No fuel came out and pipe held suction, so I’m guessing the pump is ok. First start of the day is always hard with this bike. The battery is only a few months old now, but has been on a charger (tender), all night.Any Idea why it’s tricky to start? I have to constantly press the starter button and roll the throttle on and off, also with the ‘choke’ lever.Thanks for the advice.
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Offline Soggz

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Re: Fuel in engine oil
« Reply #11 on: March 14, 2019, 05:46:18 PM »
Ok. Ran the bike again earlier, then let it sit. I think you can probably make out the fuel on top of the oil.
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Offline johnny

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Re: Fuel in engine oil
« Reply #12 on: March 14, 2019, 05:54:02 PM »

* Screenshot_20190112-155634.jpg (34.61 kB . 708x576 - viewed 524 times)
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Offline Soggz

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Re: Fuel in engine oil
« Reply #13 on: March 14, 2019, 06:26:51 PM »

* Screenshot_20190112-155634.jpg (34.61 kB . 708x576 - viewed 524 times)
lol. You might be right Johnny!
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Offline Laitch

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Re: Fuel in engine oil
« Reply #14 on: March 14, 2019, 10:00:42 PM »
Ran the bike again earlier, then let it sit. I think you can probably make out the fuel on top of the oil.
What's your diagnostic plan?
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Offline Chaos

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Re: Fuel in engine oil
« Reply #15 on: March 14, 2019, 10:19:29 PM »
don't despair,  2-stokes lead long and happy lives with a much higher percentage of fuel in their oil.
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Offline Soggz

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Re: Fuel in engine oil
« Reply #16 on: March 15, 2019, 03:45:59 AM »
What's your diagnostic plan?
Hey! Dug yourself out of the snow then?
Not sure yet.
Could be injector, could be stuck rings.... what do you think?
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Offline Soggz

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Re: Fuel in engine oil
« Reply #17 on: March 15, 2019, 03:59:55 AM »
don't despair,  2-stokes lead long and happy lives with a much higher percentage of fuel in their oil.
Helpful, thanks.
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Offline szabgab

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Re: Fuel in engine oil
« Reply #18 on: March 16, 2019, 09:00:18 AM »
You had conpression checked,  haven't you? If it was,  it will not be the rings.  If no compression test was done,  get it done as soon as...  That will tell an experienced mechanic a lot
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Offline Soggz

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Re: Fuel in engine oil
« Reply #19 on: March 16, 2019, 10:14:50 AM »
You had conpression checked,  haven't you? If it was,  it will not be the rings.  If no compression test was done,  get it done as soon as...  That will tell an experienced mechanic a lot
checked the compression. 100,150,150. Not good, but all good fun. Wondering if sticky or broke.
I remember doing a test a while ago and I’m sure all three,they were similar.
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Offline szabgab

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Re: Fuel in engine oil
« Reply #20 on: March 16, 2019, 04:08:20 PM »
checked the compression. 100,150,150. Not good, but all good fun. Wondering if sticky or broke.
I remember doing a test a while ago and I’m sure all three,they were similar.

Soggz, fortunately I have never been to the dark side of piston rings stuck or broke in their bores... What I have read on the theme, you might want to try some light penetrating oil down the bores for a day or two, especially in the low compression cylinder, probably after you have taken the bike around the block, so everything is nice and warm. After that you might want to drive the bike for an extended period and probably redline it too, so the piston rings get unstuck.
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Offline Soggz

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Re: Fuel in engine oil
« Reply #21 on: March 16, 2019, 04:56:21 PM »
Soggz, fortunately I have never been to the dark side of piston rings stuck or broke in their bores... What I have read on the theme, you might want to try some light penetrating oil down the bores for a day or two, especially in the low compression cylinder, probably after you have taken the bike around the block, so everything is nice and warm. After that you might want to drive the bike for an extended period and probably redline it too, so the piston rings get unstuck.
yes, I too have read of oils put down the bores. I can’t imagine it’s broke tbh. Stuck, maybe, yes. I will do a wet compression test in a few days. If the psi goes up. It’s got to be rings. If not, it has to be a valve, I would imagine. I’m sure it’s just where it’s been sat for so long. I will try and obtain some fine viscosity oil and pump a load down there and crank it over to get in all the gaps and let it sit for a bit. Can’t really ride it to far, as it’s not legal yet.
Thanks.
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Offline Soggz

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Re: Fuel in engine oil
« Reply #22 on: March 17, 2019, 05:16:21 AM »
REDEX. We have that here, same stuff as MMO and Seafoam, pretty much?
I’ll try some of that down them.
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Offline stokester

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Re: Fuel in engine oil
« Reply #23 on: March 17, 2019, 05:29:48 AM »
yes, I too have read of oils put down the bores. I can’t imagine it’s broke tbh. Stuck, maybe, yes. I will do a wet compression test in a few days. If the psi goes up. It’s got to be rings. If not, it has to be a valve, I would imagine. I’m sure it’s just where it’s been sat for so long. I will try and obtain some fine viscosity oil and pump a load down there and crank it over to get in all the gaps and let it sit for a bit. Can’t really ride it to far, as it’s not legal yet.
Thanks.
Not too much...  you don't want hydrolock.
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Offline Soggz

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Re: Fuel in engine oil
« Reply #24 on: March 17, 2019, 02:09:06 PM »
Not too much...  you don't want hydrolock.
Hi. No, not much. I did it this afternoon. About 10 cc or so in each. Turned it over,  I’ll leave it for a couple of days, then do the same again. Then do the wet and dry compression test.
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