3 different motors, same blow by issue (lots of gas in oil)
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Joined: Dec 2002
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From: louisiana
Those are the two main things I will be doing. Hopefully, like someone else said, if I take care of these two things then even if my side housings need lapping I will still be able to last 1k before an oil change.
Dude do you have the vent on fill tube capped off ?????????? i just run wide open and very little oil comes out if not get a vented can but make sure its not blocked in any way blow air into it and see if it clean inside..
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Joined: Dec 2002
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From: louisiana
I hope you're right...
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Joined: Dec 2002
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From: louisiana
Joined: May 2005
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From: North Bay, Ontario
If you really want to be sure that racing beat pulley is true 0* TDC, why don't you take the #1 leading and trailing plugs out, turn the engine over until an apex seal is centered in the trailing hole, mark the pulley with a pencil, then turn the engine backwards until the next apex seal is centered in the leading hole, and mark the pulley again. Check that 0* on the pulley is EXACTLY between those two marked spots.
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Joined: Dec 2002
Posts: 10,116
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From: louisiana
Really? Is this what people have to do everytime they get a pulley from racing beat? I thought all 86-91 motors had the same timing? I guess if worse comes to worse than I'll have to do this even though it'll be a bitch since the motor is in the car already.
Could racing beat really sell a pulley like this and not be held liable for people's motors blowing up because the timing isn't correct?
Could racing beat really sell a pulley like this and not be held liable for people's motors blowing up because the timing isn't correct?
Last edited by hondahater; Dec 17, 2009 at 11:08 AM.
Joined: May 2005
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From: North Bay, Ontario
I was always told that they were dead-on, since they are 1 piece, and the e-shaft key is the same, regardless of year, etc. So it should be fine, but if you were concerned, it's not that hard to check
Really? Is this what people have to do everytime they get a pulley from racing beat? I thought all 86-91 motors had the same timing? I guess if worse comes to worse than I'll have to do this even though it'll be a bitch since the motor is in the car already.
Could racing beat really sell a pulley like this and not be held liable for people's motors blowing up because the timing isn't correct?
Could racing beat really sell a pulley like this and not be held liable for people's motors blowing up because the timing isn't correct?
The condition of your Irons would surely aid fuel in getting past the side seals but I'm telling you that this is still a pretty common problem. The more boost your run the higher likelihood that the "richer" mixture you're running will be able to pass the gap of your sideseal.
If you motor makes good power and the car pulls I wouldn't worry about it. I'm quite confident that your motor is in good shape as you're a reputable person. Gasoline isn't good for most rubber seals but if you have the viton oil control rings you're in a little better shape.
I'm still pretty sure that changing your oil every 1000 miles and putting some tuning time will help but not completely dissolve your problem. Just like in life you can never expect one change to be the complete solution, sometimes it's the little things all added together that make the difference. Okay I'm done
If you motor makes good power and the car pulls I wouldn't worry about it. I'm quite confident that your motor is in good shape as you're a reputable person. Gasoline isn't good for most rubber seals but if you have the viton oil control rings you're in a little better shape.
I'm still pretty sure that changing your oil every 1000 miles and putting some tuning time will help but not completely dissolve your problem. Just like in life you can never expect one change to be the complete solution, sometimes it's the little things all added together that make the difference. Okay I'm done
I don't mean to distract from anything that's already been said (removing plugs and marking the pulley is a pretty cool idea, BTW)... but will your ECU allow you to adjust the injector phasing (the crank angle when the injectors are fired, not the pulsewdth)?
My theory is that the intake ports are open sometimes and other time the intake ports are 'closed' because the side of the rotor is covering them and preventing air from getting in the chamber. I suspect that shooting fuel at the side of the rotor would encourage fuel to mix with the oil, especially if you're running big injectors. Shooting fuel into an open port might result in less fuel mixing in the oil and maybe a richer AFR given the same pulsewidth. There was a pretty cool diagram showing port opening vs. crankshaft angle on the yawpower.com site.
Just my opinion so feel free to take it with a grain of salt... unfortunately I don't have much data to back it up.
My theory is that the intake ports are open sometimes and other time the intake ports are 'closed' because the side of the rotor is covering them and preventing air from getting in the chamber. I suspect that shooting fuel at the side of the rotor would encourage fuel to mix with the oil, especially if you're running big injectors. Shooting fuel into an open port might result in less fuel mixing in the oil and maybe a richer AFR given the same pulsewidth. There was a pretty cool diagram showing port opening vs. crankshaft angle on the yawpower.com site.
Just my opinion so feel free to take it with a grain of salt... unfortunately I don't have much data to back it up.
this is also a good reason why i don't lap housings, especially on an engine that has to go through such a rich in fuel trial before being tuned. i'm guessing the irons were lapped anyways..
Thread Starter
Joined: Dec 2002
Posts: 10,116
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From: louisiana
The condition of your Irons would surely aid fuel in getting past the side seals but I'm telling you that this is still a pretty common problem. The more boost your run the higher likelihood that the "richer" mixture you're running will be able to pass the gap of your sideseal.
If you motor makes good power and the car pulls I wouldn't worry about it. I'm quite confident that your motor is in good shape as you're a reputable person. Gasoline isn't good for most rubber seals but if you have the viton oil control rings you're in a little better shape.
I'm still pretty sure that changing your oil every 1000 miles and putting some tuning time will help but not completely dissolve your problem. Just like in life you can never expect one change to be the complete solution, sometimes it's the little things all added together that make the difference. Okay I'm done
If you motor makes good power and the car pulls I wouldn't worry about it. I'm quite confident that your motor is in good shape as you're a reputable person. Gasoline isn't good for most rubber seals but if you have the viton oil control rings you're in a little better shape.
I'm still pretty sure that changing your oil every 1000 miles and putting some tuning time will help but not completely dissolve your problem. Just like in life you can never expect one change to be the complete solution, sometimes it's the little things all added together that make the difference. Okay I'm done

I don't mean to distract from anything that's already been said (removing plugs and marking the pulley is a pretty cool idea, BTW)... but will your ECU allow you to adjust the injector phasing (the crank angle when the injectors are fired, not the pulsewdth)?
My theory is that the intake ports are open sometimes and other time the intake ports are 'closed' because the side of the rotor is covering them and preventing air from getting in the chamber. I suspect that shooting fuel at the side of the rotor would encourage fuel to mix with the oil, especially if you're running big injectors. Shooting fuel into an open port might result in less fuel mixing in the oil and maybe a richer AFR given the same pulsewidth. There was a pretty cool diagram showing port opening vs. crankshaft angle on the yawpower.com site.
Just my opinion so feel free to take it with a grain of salt... unfortunately I don't have much data to back it up.
My theory is that the intake ports are open sometimes and other time the intake ports are 'closed' because the side of the rotor is covering them and preventing air from getting in the chamber. I suspect that shooting fuel at the side of the rotor would encourage fuel to mix with the oil, especially if you're running big injectors. Shooting fuel into an open port might result in less fuel mixing in the oil and maybe a richer AFR given the same pulsewidth. There was a pretty cool diagram showing port opening vs. crankshaft angle on the yawpower.com site.
Just my opinion so feel free to take it with a grain of salt... unfortunately I don't have much data to back it up.
Thanks for the replies everyone, it's much appreciated!!!
With my large streetport I don't have any blowby problems. I have the s4 OMP and I use oil at a normal rate. My cruising EGT's are 1000-1300 F preturbo. Side seals are all clearanced to .002" +/- .00025" spec is .002 - .0059
I also agree that your timing map seems too retarded in cruising. With a half bridge I'd run up to 25 degrees around the idle area, but you really should be 30 - 50 degrees in low load vacuum areas with 0 - 3 split in most areas. Some people run negative split but only under very low loads.
I also agree that your timing map seems too retarded in cruising. With a half bridge I'd run up to 25 degrees around the idle area, but you really should be 30 - 50 degrees in low load vacuum areas with 0 - 3 split in most areas. Some people run negative split but only under very low loads.
I just changed my oil last week and this week I'm about a quart or a quart and a half over the fill line today (so lots of gas in the oil).
I am running a bit rich during cruise at about 10.5 or so but am working on the cruise map as we speak.
You need to watch out for when the engine is doing the bridge port stutter, though - that will add extra oxygen to the exhaust and make the readings leaner than actual. Even my street port will do the stutter under super low load conditions,, so at that point I just ignore the wideband entirely and go by feel. My maps always end up with a "hammock" between 40 and 80kpa and 1200 to 4000rpm. (I don't consider running over 4000 to be cruising, with the nice tall gearing I use
)
I'll probably be in the 12-13 range when finished (half bridge port). If this clears up the problem then great but somehow I don't think it's this because I've got a pretty good ignition system that should be able to burn most if not all of this (4 crane coils and 2 hi-6 amps and microtech x4 box).
Anyways my question is this. I've got nothing setup to handle my blowby (no catch can) I've only got the upper nipple on the oil filler tube vented to atmosphere and I barely get anything out of it at all. Should I have anything other than this setup to pull it out like a vac hose coming from before the turbo going to a catch can along with a hose coming from the oil fill tube? Just looking for some pointers on this because this blow by thing is killing me!
My Plan for this winter is to put the air pump back on and route the oil filler to a labyrinth catch can (okay, a GM style A/C accumulator) and the air pump will pull everything under a slight vacuum.
Me too
I have the same issue. For me it's mainly a tuning issue. Thats why I run cheap oil while I tune, and switch to Royal Purple once I'm ready to power/boost tune. Once I tune its not too bad unless I race/boost.
I have also noticed if I idle for a long period of time it is worse. I think leaking/sloppy injectors and porting may play into it. My engine idles great at 12.5 but once I get my new IAC I'm going back to a 13.5-14 idle to fix this.
If you find a smoking gun/black leather glove that fits let me know!
I have also noticed if I idle for a long period of time it is worse. I think leaking/sloppy injectors and porting may play into it. My engine idles great at 12.5 but once I get my new IAC I'm going back to a 13.5-14 idle to fix this.
If you find a smoking gun/black leather glove that fits let me know!
Thread Starter
Joined: Dec 2002
Posts: 10,116
Likes: 1
From: louisiana
All rotaries do this to some degree. Mazda engineered a quick-change into the oil so they could change the oil during endurance races, back in the early 80's.
It takes me about 2,000 miles (one or two rallycrosses, plus maybe 10-15 quarter mile passes) to get to that point. I change the oil every month (how long it takes me to get to that point) and the filter once a year.
A BIT!!! Get that sucker leaned out! I'm running 15 to 16.5 at anything not idle or over 80kpa absolute. Basically I keep leaning it out until power goes away and it starts misfiring, then add half a point. Under cruise it will be making maybe 20-30hp so you're not hurting a thing. A half-bridge may require more fuel to run acceptably smooth but the same principle applies - just give it enough fuel to run cleanly.
You need to watch out for when the engine is doing the bridge port stutter, though - that will add extra oxygen to the exhaust and make the readings leaner than actual. Even my street port will do the stutter under super low load conditions,, so at that point I just ignore the wideband entirely and go by feel. My maps always end up with a "hammock" between 40 and 80kpa and 1200 to 4000rpm. (I don't consider running over 4000 to be cruising, with the nice tall gearing I use
)
If it is richer than 14.7 then by definition you will not be able to burn all of the fuel. Even with running lean, you're not going to be able to burn all of the fuel because some of it will always end up in the corners of the combustion chamber where the flame can't really get to it.
I run something similar, a hose coming off of the fill pipe goes to a catch bottle. Mostly the bottle fills with oily water vapor, and by "fills" I mean I added about 5oz of goo in about 8,000 miles.
My Plan for this winter is to put the air pump back on and route the oil filler to a labyrinth catch can (okay, a GM style A/C accumulator) and the air pump will pull everything under a slight vacuum.
It takes me about 2,000 miles (one or two rallycrosses, plus maybe 10-15 quarter mile passes) to get to that point. I change the oil every month (how long it takes me to get to that point) and the filter once a year.
A BIT!!! Get that sucker leaned out! I'm running 15 to 16.5 at anything not idle or over 80kpa absolute. Basically I keep leaning it out until power goes away and it starts misfiring, then add half a point. Under cruise it will be making maybe 20-30hp so you're not hurting a thing. A half-bridge may require more fuel to run acceptably smooth but the same principle applies - just give it enough fuel to run cleanly.
You need to watch out for when the engine is doing the bridge port stutter, though - that will add extra oxygen to the exhaust and make the readings leaner than actual. Even my street port will do the stutter under super low load conditions,, so at that point I just ignore the wideband entirely and go by feel. My maps always end up with a "hammock" between 40 and 80kpa and 1200 to 4000rpm. (I don't consider running over 4000 to be cruising, with the nice tall gearing I use
)If it is richer than 14.7 then by definition you will not be able to burn all of the fuel. Even with running lean, you're not going to be able to burn all of the fuel because some of it will always end up in the corners of the combustion chamber where the flame can't really get to it.
I run something similar, a hose coming off of the fill pipe goes to a catch bottle. Mostly the bottle fills with oily water vapor, and by "fills" I mean I added about 5oz of goo in about 8,000 miles.
My Plan for this winter is to put the air pump back on and route the oil filler to a labyrinth catch can (okay, a GM style A/C accumulator) and the air pump will pull everything under a slight vacuum.
Sounds like the timing issue I had. 10 AFRs at cruise with super hot EGT's. My fuel map wasn't uber rich so I didn't have the oil issue but what your describing sounds like the CAS isn't stabbed properly. You may be close as mine started and drove but had 2/3 of your symptoms.
Oh the post above reminded me of something. I have 3 engines in my shop; one that I pulled out of my car that was running like crap, one I bought from Hinson that was thought to be blown and one that has 5k on it that was built by KDR. All 3 had the tabs on the CAS broken and were leaning over. They kind of dryrot and become brittle. this would creat havoc with your timing but then again it would have been caught during the first rebuild. Anyway look down there and check both of them and make sure one isn't wiggling around.
Thread Starter
Joined: Dec 2002
Posts: 10,116
Likes: 1
From: louisiana
Thanks fellas. I just heard back from Brian at BDC. If all goes well (which it usually doesn't with this particular car) He'll be coming down here to tune it at some point and when it's finished we'll see how much blow by I get afterwards. If it's still up there then I guess one of these days when I feel like taking the motor apart for a 4th time I'll have the housings resurfaced.
ya keep us updated, im running into the same problem myself with 720/1600cc injectors, my oil level goes up and when i looked in my vented catch can, i had raw fuel in there.
brand new primaries, one new secondary and the other was cleaned.
i been changing my oil every 1,500 but may have to do 1k now.
i get 14.7during cruise, bout 1200-1400* EGT post turbo w? bout 28* advance. idle is 13.5 when warm and bout 12.3 when cold. i removed fuel during decel and i just got bout 12mpg on last tank full yet oil has lots of fuel.
i dont boost the car that much and i do see 10-11 afr when cold from 1k to 3k rpms. this is on a streetport.
brand new primaries, one new secondary and the other was cleaned.
i been changing my oil every 1,500 but may have to do 1k now.
i get 14.7during cruise, bout 1200-1400* EGT post turbo w? bout 28* advance. idle is 13.5 when warm and bout 12.3 when cold. i removed fuel during decel and i just got bout 12mpg on last tank full yet oil has lots of fuel.
i dont boost the car that much and i do see 10-11 afr when cold from 1k to 3k rpms. this is on a streetport.





