na, BOV on mine since the turbo was on there, i never spooled the turbo up without a bov and mine still went out. never up the boost either.

i have heard some opinions that the oil drain is a bad design, the spout coming out going to the oil pan, that it does not drain quick enough for a car with high rpms thus oil backs up, but oil is still coming into the turbo. there goes the seals.

I don't know the alternative oil drain though, does anyone else know other ways to drain a turbo, how is a stock turbo set up?
greddy turbos have also been very unrealiable in hondas also, same oil drain, or so i heard.

 

Well on TIIs the oil drain is not that disimilar,but it flows into the front cover.In my mind the more significant difference is water cooling of the turbo--according to Mazda data when the engine is shut down the metal of the turbo is about 302F lower with water cooling.So the risk with the Greddy is that if you do not manage the heat very carefully you fry the seals and bearings

 

maybe so, then an extra oil cooler might help, i dunno, if its oil temps then any oil cooled turbo would be prone to fail though, are that they unrealible on other vechicles?

 

Oil temperature inside the turbo when you shutdown the engine is the issue.If the metal of the turbo is too hot,the oil in contact with it will carbonise and the carbon grit and sludge will chew up the seals/bearings when the engine is restarted.
I think careful management prior to shutdown is the only way and the best oil you can buy(whatever that is).

 

sorry to hear about your turbo guys, now im having a second thought about installing the kit (GREDDY), i have gotten my turbo kit finally NOV 18 05 to be exact, and now this Thread mmmmm?????
i think im just gonna sit on it for a while till somebody works the bugs out.
i like to boost ......someday,but i love driving my 8 TURBOED or NOT.
Daily Driven
PLEASE PLEASE PLEASE ROTARY GOD find a cure for our GREDDY KIT.

 

You've had it since NOV 18 05??? Wow, you've gots some patience, or just lazy. If it was me, it would have been in nov19,05.

I installed my greddy turbo 1 month after philodox and the turbo has almost 10k miles on it now. I've been running 10psi now for about a month with the interceptor X. Runs very good.
My turbo hasn't given me any problems at all (knock on wood). My probs were with cats breaking up, boost line leak, and the emanage w/ R-flash.

 

I was always EXTREMELY **** about shutting my car off after anything close to hard running. MY GF hated driving in my car until I got my turbo timer because she hated waiting for 5min while I let it cool down. Plus most other aftermarket turbos aren't water cooled and they don't break.

I was talking to turbonetics today and they said one of the leading causes of turbo failure is improper oil pressure. So perhaps the routing of the oil line, or the diameter of the oil line is incorrect and that is the cause of the failures.

 

I have a completely random idea, and really don't know if it would help or is possible. But maybe if you had the GReddy oil pan, with 2 spouts on the side, you could design some sort of oil return line shaped like a Y. That way it would allow more oil to flow out, and not get backed up.

 

I spoke about the problem with Rick from Rotary Performance, and he has an intersting opinion that makes sense. I'll try to relay what he was saying. When he installed PURNRG's turbo, and oil pressure gauge, he noticed that the pressure was significantly lower than what he had seen in previous generation turbocharged rotaries. He thought this may be a problem on his own turbocharged 8, so he has been running thicker weight oil, and this will make a small increase in the pressure. But apparently the problem has more to do with the engine design itself. When he rebuilt Saphonicca's engine, he noticed that our oil pump is only about the size of the 12A's pump, so its undersized. Although this may be fine while N/A, while turbocharged, its not going to allow the turbo to receive enough pressure, especially at lower rpms. This in turn will lead to the hot oil clogging up inside the turbo, and eating away at the bearings. He also said that when he was putting Saphonicca's car back together, he upgraded a part in the oil system. I can't remember what the name was, but it was by Racing Beat, and can be accessed by removing the oil pan. We also discussed how GReddy should have done more research into the characteristics of the engine before they released the kit, but more than likely, the problems people are starting to have aren't with their turbo kit at all, but with the engine itself. Maybe some gurus out there could do some research into this as soon as possible. If all these turbo's are starting to go bad in the winter, the summer is going to be very expensive for some of us.

Discuss!

 

[QUOTE=Moostafa29]I spoke about the problem with Rick from Rotary Performance, and he has an intersting opinion that makes sense. I'll try to relay what he was saying. When he installed PURNRG's turbo, and oil pressure gauge, he noticed that the pressure was significantly lower than what he had seen in previous generation turbocharged rotaries. He thought this may be a problem on his own turbocharged 8, so he has been running thicker weight oil, and this will make a small increase in the pressure. But apparently the problem has more to do with the engine design itself. When he rebuilt Saphonicca's engine, he noticed that our oil pump is only about the size of the 12A's pump, so its undersized. Although this may be fine while N/A, while turbocharged, its not going to allow the turbo to receive enough pressure, especially at lower rpms. This in turn will lead to the hot oil clogging up inside the turbo, and eating away at the bearings. He also said that when he was putting Saphonicca's car back together, he upgraded a part in the oil system. I can't remember what the name was, but it was by Racing Beat, and can be accessed by removing the oil pan. We also discussed how GReddy should have done more research into the characteristics of the engine before they released the kit, but more than likely, the problems people are starting to have aren't with their turbo kit at all, but with the engine itself. Maybe some gurus out there could do some research into this as soon as possible. If all these turbo's are starting to go bad in the winter, the summer is going to be very expensive for some of us.

Discuss![/QUO

MOOSTAFA , THAT'S REALLY IS NOT AN OIL PRESSURE SENSOR , IS A PRESSURE SWITCH WITH A PROGRAMATED GAGE SCALE. WHEN I REMOVE SENSOR FROM THE ENGINE I NOTICE THAT'S ONLY A PRESSURE SWITCH INSTEAD OF PRESSURE SENSOR.

 

You are talking about something completely different. I'm refering to an aftermarket gauge, not the switch that you remove and hook the supply line up to.

 

According to the Manual,the reference oil pressure in Renesis is 51psig at 3000rpm,with oil temperature of 100C.This is about the same as the spec for a TII.I checked the oil pump size for the TII,and it is about 50% greater than a 2nd gen NA.

 

Oops,I intended to ask what kind of oil pressure those with proper oil gauges are seeing?

 

talk amongst your selves guys, we might just find out what the deal is with these turbos!

 

Hmm. I put a restrictor in my oil line when I installed it - I was worried about the oil pressure being to high coming straight off of the sender.
I've done this on all of my turbo cars. Turbos need very little oil. Too much pressure with blow the seals and too much flow will do strange things to the bearings.

The oil source tube that comes with the Greddy kit is huge compared to mine as well - it is nearly twice the inside diameter (outside too) and a good 6 inches shorter.

I am about to install a Greddy turbo/manifold on Monday (just 'cause I can - how do you like them apples ) while I take my turbo/manifold off for investigation (I have a small exhaust leak on the engine side of the tube between the center and rear ports and I am building a better version of the manifold, so I need it off the car for a while but I can't stand to be without turbo for any length of time), so I will be able to give you all a little report on the kinds of minimum pressures the turbo can take.

BTW - the draining issue isnt the quality of the drain itself - it is the position of the turbo.
Fluid holds its own level and the bottom of the turbo is already really close to the top of the oil level in the sump. This means the drain rate isn't going to be very fast.
The trick is to only get the oil moving through the turbo via gravity and no more.

 

I've seen cars with a very low mounted turbo that had their own small pump to help move the oil through the turbo. I believe this was on a Corvette and the turbo/s were actually mounted below the engine. It had a small electric oil pump. perhaps someone could try this. If MazdaManiac really believes that oil getting backed up in the turbo could be a problem.

 

Corky Bell mentions that kind of thing in his book.
I don't know if backed up oil or incorrect pressure is the culprit, though I would bet that it is high pressure that is doing it in.

 

Isn't the factory drain location that the Greddy turbo return line uses below the oil level of the pan? Otherwise how would the oil drain during an oil change? It seems to me that this isn't a good idea for drainage, unless enough oil is circulating through the engine when running to pull the level down sufficiently.

 

the turbo drain is higher than the oil pan drain.

 

You mean with the Greddy oil pan? Alot of us are still using the stock pan.

 

well mm was talking about the oil feed line so i thought i say yeah, my new oil feed line i bought was much smaller than the greddy one and a little longer.

What exactly is an oil restrictor, where do we get them, and how do we know if the turbo is getting enough oil?

mm, ya may have found the problem, my seals were gone and of course bearing, this may be the culprit!

 

I made my own restrictor, but you can get on from any turbo supply place.
It is just a little brass insert that goes inside the feed fitting on top of the turbo with a smaller orifice than the hose. I think it is .035", but I'm not sure at the moment.

 

of course ya made your own, ya da man!

if i get the specs on my oil feed and pm them to you would you mind looking at them to make sure the restrictor will not cut too much oil off? this is kinda techy for me, i am learning as i go, the only way to learn, but sometimes expensive way

 

i'm gonna agree with MM on this issue i think that the pressure of the oil is gonna be the culprit i was talking to a friend about it last night and thats the only thing that we could think of that could cause this problem that or the fact that the turbos are just junk. now about drainage though the pressure would be low (with restrictor) it should still be enough to flow through turbo unless your oil pan somehow became pressurized but thats just my $.02

 

Our turbo is a common turbo that many people have been using for a long time without problem. Granted Greddy does modify it, but I believe the bearings and seals are still standard Mitsubishi style. At the very least the 350z's twin turbo setup uses a similar turbo, TD05-18g, and I was checking the 350z forums the other day and they don't seem to be having a problem. So, while they're not the greatest turbo, I don't think they're junk either. I think the oil pressure is a likely culprit. Maybe if we put a pressure gauge on the line, and measure the pressure, we can confirm with Greddy if that is what they expected when they designed the kit.