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-   -   Holy Smokes (omp Question)! (https://www.nopistons.com/rotary-engine-building-porting-swaps-55/holy-smokes-omp-question-40744/)

heretic 06-20-2004 01:19 PM

It's coming from the turbos. If it was from the engine, the oil would be introduced into the engine when the rotor passed over the intake ports, applying vacuum to the area between the oil seals and the side seals. Then the oil would be mostly burned, converted to smoke if you will by the act of combustion.



Another good test is to pull the spark plugs. If they look like they were dragged face-down through a Chevy oil pan, you're burning the oil. If they look fairly clean with no massive oil sludge, then it's coming from the turbos. (edit: n/m, didn't see you were going to check that, but it's nice to have confirmation that it's a good idea, no?)



Before you blame the magic snails, make sure you have good, clear oil returns, and that the oil returns don't have to go uphill, and that the oil level in the engine is not higher than the return's entry point. Turbos need large, clear oil returns or they can start puking oil past the seals.

boost_this 06-20-2004 03:24 PM

Well, I pulled the plugs and they looked real clean, Leading plugs were clean and dry, trailing had some carbon and a bit of wetness on the tops but not much at all...rechecked compression and got 120 in rear and 95 in the front...not really happy with the big difference but I know I had some questionable side seals/springs that I used anyways thinking they looked fine so that might explain the difference.



I pulled the OMP and installed the K2RD block off plate, warmed the car up kept it at a steady 3000 rpm to burn out whatever oil was in there the engine runs smooth at 3k but man it fogged up the neighborhood!!! So ruled out the OMP...will prob leave it off and pre-mix for piece of mind.



That leaves oil rings or turbo... The turbo looked great (only had 20K on it) and was relatively dry inside prior to putting it on......pulling turbo now and will take a look at the exhaust ports to see how oily they are. I hate to say this but I hope it the turbo seals. I have two rebuild kits from turbo city ready to go.



Has anyone ever seen the turbo exhaust oil seal blow before...I thought it was mostly intake sides that go?



I appreciate the comments.



Thanks,



Chris

Fd3BOOST 06-20-2004 03:48 PM

Chris my money is on the turbo but I'm glad you seem to be making progress in either case. Anyway I am done with mine for the day, very little left to do. Really only left with the rack to mount the coils and the pipe that needs welding. Anyway I'll leave the hood unlatched if you wanna have a peek. Leslie and I are off to BBQ with the folks. The fans are sitting out for you. Good luck.



-Dave

j9fd3s 06-20-2004 04:29 PM

ive seen the exhaust side of the turbos die before

boost_this 06-20-2004 07:19 PM

Well I pulled the DP/turbos off and found alot of oil in the DP leading to some oil on the inside of the y-pipe that joins the two exhaust snails as it exits to the downpipe....but no real wetness around the wheels at all where the oil would have to come from???



The exhaust ports on the motor looked real dry but I still wasn't completely convinced it was the turbos so I decide to try and run the motor with no manifolds to confirm any oil being spit out of the motor. I ran the turbo oil pip to the oil return in block and then ran it for 30 seconds at a time unil I got the motor up to full temp (I DONT RECOMMEND THIS TO ANY ONE WITH AN OILY ENGINE BAY).... because those BLUE FLAMES shooting out the exhaust port will light it up! Anyways, happy to report no smoke at all and no oil on the piece of aluminum I put infront of the exhaust ports to shield the body from the exhaust.



So I think I just confirmed I need to rebuild my turbos (damn things are only suppose to have 20k on them)!!!!!! I plan on knocking that out this week and hopefully move on to other things like my fans, miss at idle, small coolant leak etc.



I will post some pics later tonight.



Chris

Fd3BOOST 06-20-2004 08:39 PM


Originally Posted by boost_this' date='Jun 20 2004, 04:19 PM
Well I pulled the DP/turbos off and found alot of oil in the DP leading to some oil on the inside of the y-pipe that joins the two exhaust snails as it exits to the downpipe....but no real wetness around the wheels at all where the oil would have to come from???



The exhaust ports on the motor looked real dry but I still wasn't completely convinced it was the turbos so I decide to try and run the motor with no manifolds to confirm any oil being spit out of the motor. I ran the turbo oil pip to the oil return in block and then ran it for 30 seconds at a time unil I got the motor up to full temp (I DONT RECOMMEND THIS TO ANY ONE WITH AN OILY ENGINE BAY).... because those BLUE FLAMES shooting out the exhaust port will light it up! Anyways, happy to report no smoke at all and no oil on the piece of aluminum I put infront of the exhaust ports to shield the body from the exhaust.



So I think I just confirmed I need to rebuild my turbos (damn things are only suppose to have 20k on them)!!!!!! I plan on knocking that out this week and hopefully move on to other things like my fans, miss at idle, small coolant leak etc.



I will post some pics later tonight.



Chris

Chris It's always been told to me by Peter and a few other "pros" that any stock twin with over 10k will blow by alot of oil and 20k is damn near shot. Food for thought. Well i guess you didn't get a chance for the fan issue yet as I got home and they are still here. I will leave them out for you just in case for the next few days.

heretic 06-20-2004 09:24 PM


Originally Posted by boost_this' date='Jun 20 2004, 12:24 PM
Well, I pulled the plugs and they looked real clean, Leading plugs were clean and dry, trailing had some carbon and a bit of wetness on the tops but not much at all...



(...)



That leaves oil rings or turbo...

No, it just leaves turbo. If that much oil was going past the oil control O-rings, the spark plugs would be heavily fouled, probably to the point of misfiring, even after only a few minutes.



But you now know this already...

boost_this 06-20-2004 09:28 PM

Dave, thanks for the effort, I meant to pick them up but got too worked up on chasing down the smoke. I will pick them up tomorrow. I am just happy that it looks to be the turbos and not the motor itself. Although I am a little pissed about paying 400 bucks for turbos that need a rebuild https://www.nopistons.com/forums/pub...O_DIR#>/11.gif



Anyways, I hope to have it together in the next couple of days so I can confirm then try to get some of my money back from that dude.



Chris

boost_this 06-20-2004 09:34 PM

Thanks to all for bits of common sense and sanity checks today. Its always nice to hear someone else confirm your suspicions. I was running back and forth between the garage and computer all day long searching through the forums for those that had similar problems.



I will report the progress and post some pics later this week.



Hey, while I have the turbos out and am doing a rebuild has anyone ever gone through the trouble of machining out the turbo pre-control flapper/casting? It seems everyone wires them open anyways when going non-sequential. Are there any measurable gains from removing the round flapper and the webbing associated with it?



Thanks,



Chris

boost_this 06-21-2004 07:45 PM

Pulled the turbos apart tonight..... check out the pic of the crack in primary wastegate...hhhhmmmmm, do you think that had anything to do with it?? https://www.nopistons.com/forums/pub...IR#>/angry.png https://www.nopistons.com/forums/pub...IR#>/angry.png Trying to contact the seller of these "ready to run, low mileage turbos" right now!



Chris


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