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-   -   Fuel getting in the oil? (https://www.nopistons.com/rotary-engine-failure-discussion-102/fuel-getting-oil-74994/)

thatpoorguy 12-11-2010 02:11 PM

I had a shop rebuild my engine not too long ago and now about 18 mo. Later I'm starting to have some issues. It's a 13b rew with single conversion and street ports.



The problems started last winter when it started not wanting to stay running after startup when it was near freezing out. Then I noticed my oil level wasn't getting lower between oil changes like it should, but instead increasing and it smells like fuel. I thought maybe it was

doing that cause I flooded it a couple times. But it kept

doing the fuel in oil thing during the summer too even though I didn't flood it at all that summer. I can't think of anything that would cause the fuel to find passage to the oil pan so i'd really like some advice on what it could be before the engine has a major breakage

1988RedT2 12-11-2010 04:37 PM

Hopefully, someone will correct me if I am wrong, but so far as I know, the only way for fuel to get into your oil is via a too-rich mixture. I can detect some fuel smell in my oil after just a few hundred miles, but I know that I'm way too rich, with AFR's around 10.0 at full boost. I make it a point to change my oil frequently, but this car sees very little mileage--way less than 1000 miles a year.



Any way to verify what kind of AFR's you're running at cruise and full boost? How's your gas mileage? Are you running the stock ECU or an aftermarket? Things like a bad coolant temp sensor can cause the computer to run the engine very rich.

thatpoorguy 12-11-2010 06:03 PM

No, I know why it's running rich. When the shop put the break in tune on it they set it rich so it wouldn't detonate on break in. I haven't been able to afford to take her in for her final tune and I drive her fairly frequently. It floods a LOT during the winter months and my af gauge is always rich. I guess I just need to save up and get it tuned in the spring :/

thatpoorguy 12-11-2010 06:10 PM

I'm running a power fc with walboro pump, 850 primaries and 1600 secondaries. My gas mileage blows :P

1988RedT2 12-11-2010 07:22 PM

Yeah, you're just hosing down the combustion chamber with raw gas. Some of it is going to end up in the oil. Get it tuned when you can. In the meantime, change your oil OFTEN. Gas does bad things to oil and it's not going to lubricate and protect the internals.

thatpoorguy 12-11-2010 07:46 PM

Yeah, unfortunately their tunes aren't cheap and they are booked till spring :/

j9fd3s 02-20-2011 03:09 PM

i notice with the PP, that in the tuning phase with a lot of idling, slow driving while running rich the oil got dark and fuel smelly really quick. out on the track though, the oil stayed clean, and it doesn't smell at all, which was a happy surprise...



anyways, if you have an O2 sensor, or WB, you can start leaning out the cruise areas yourself. with the PFC its a little tricky, you have to go look at all the settings, there is a way to richen the whole map globally, and you need to make sure the engine guy didn't do that.



if he didn't do that, you can use the map trace while just cruising, and lean it out in those cells. if you're just cruising under 3200rpm, AFR should be 14.7:1, richer than that and you're just wasting gas, and ruining the oil

thatpoorguy 02-21-2011 09:07 AM

What kind of software and hook ups do I need? The power fc was on the car when I bought it so I didn't get any goodies that came with it.

j9fd3s 02-21-2011 12:45 PM


Originally Posted by thatpoorguy (Post 846834)
What kind of software and hook ups do I need? The power fc was on the car when I bought it so I didn't get any goodies that came with it.



dataloggit would be the best, but you can use the commander too

thatpoorguy 02-22-2011 12:14 PM

You can tune from the commander? I need to get the directions from a'pexi because I didn't even know that lol


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