Is this amount of oil normal?

Discuss the RB20, RB25 and RB26 series engines.
AxiOn419
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I was cleaning up the engine today before I put it in the new car and came across this. Seems to be a good amount of oil in the intake. I dont know if this is normal or not. The shop that put the engine in (3 years ago) removed the recirculating hose so that it would blow off atmospherically. The car didnt idle right so I attached a hose from the recirculating valve back to the intake, which fixed the idle problem. The recirculating valve does blow some oil down into the intake. Is this too much oil?





Thanks for the help in advance


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BoostFab
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that is way too much oil.

look in your intercooler, see if there are oil in there also! your turbo compressor seal probably may be bad.

AxiOn419
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I just checked the intercooler, there appears to be a bit of oil on one side, but then again this engine has been sitting up for over a year because I was involved in a wreck so it is hard to tell how much was in there when the engine was in use.

If someone could clear this up as to why that much oil is there and what I need to do to fix it I would appreciate it. Also, how do I go about chekcing the turbo compressor seal?


Cpt_Impossible
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A light layer of oil is normal, like a film... but that looks like way more than normal. Was the engine stored somewhere really humid or outside or something? If you put a catch can between the valve covers and where it goes back into the intake it will keep that from happening again, and it will let you gauge just how much oil you are losing and at what rate. Some people put some steel wool or chain in the catch can to help it trap more moisture.

AxiOn419
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Yes it was stored outside under a cover. I just pulled off the spark plug covers and it appears I am in a whole other world of trouble there. Each slot where the plugs are is flooded with oil and water. It is nasty. I will get a picture.

AxiOn419
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Cpt_Impossible wrote:A light layer of oil is normal, like a film... but that looks like way more than normal. Was the engine stored somewhere really humid or outside or something? If you put a catch can between the valve covers and where it goes back into the intake it will keep that from happening again, and it will let you gauge just how much oil you are losing and at what rate. Some people put some steel wool or chain in the catch can to help it trap more moisture.
Oh and how exactly do I go about putting a catch can between it? I am sort of confused as to the setup you explained. If you could show me a picture that would be awesome. That sounds like a good idea, something I might need to try.

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fast_s13
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last time i seen that much oil in a intake of an rb the ringlands were gone between the rings...... so you may want to do a compression check

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Abdo
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That sucks man.. Just hope it's your compressor seal and not the ring lands.Good luck anyways.

fly240
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hey, my rb25 has the same thing....oil all around the intercooler pipes ..it must be bad seal....because last summer, i raced and the turbo is totally smoke out of the exhaust....talking about hugh smoke.....

nismopwr240
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my guess would be that the compression is low, get a compression tester from sears and find out

AxiOn419
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Thanks for all the responses. I have a compression test tool and I will use it when I get home to see. I read earlier the proper process for testing compression.. isnt it as easy as screwing in the tool then cranking the engine over (not electronically but using a big wrench)?

Also, 170 +-5 is normal across all cylinders, correct?

If it is the ringlands, is it worth fixing? If its just a compressor seal, how hard is that to change/find a seal?

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Abdo
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AxiOn419 wrote:If it is the ringlands, is it worth fixing? If its just a compressor seal, how hard is that to change/find a seal?
Well it's definitely a good excuse to rebuild your motor with forged internals.

AxiOn419
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Hmmm, that might be a little bit expensive and a daunting task for me. If thats what it needed I would probably be better off selling the motor and getting an RB25.

This may be a stupid question but what exaclty is a ringland and why does oil in the intake point to that being the problem? If someone could give me an overview of what happens inside the engine when you have bad ringlands that would be great, this whole engine swap process is a big learning experience for me.

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nizmo zilvia
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Yea I bet your piston rings are no good and since it was stored the way it was all the oil probably leaked. Or when it ran.

I strongly suggest you take off your head and see whats going on with your pistons. Then take off the oil pan and see how the rods are.

OR maybe even your turbo seal is no good so its leaking oil out aswell but Im not positive on that. Eitherway its not looking good.

nismopwr240
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search "pcv valve" in wikipedia, this explains what is being talked about. If the rings, or ringlands are bad, a lot of oil (blow by) gets passed the pcv valve and into the intake, causing pools of oil as shown in the photos.

Darius
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Just swap it in and fire it up. Half of our motors sat in a junkyard for years before being shipped over to the US. If it blows and/or the rings are shot, THEN rebuild it.

Can you manually crank the engine over with a socket wrench? i.e. its not siezed up.

AxiOn419
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Darius wrote:Just swap it in and fire it up. Half of our motors sat in a junkyard for years before being shipped over to the US. If it blows and/or the rings are shot, THEN rebuild it.

Can you manually crank the engine over with a socket wrench? i.e. its not siezed up.
Yes, I can manually crank it and its fairly easy to do actually, has a very fluid feel to it. All pulleys and such turn great.

I am going to read about the pcv vavle right now, thanks

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fast_s13
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AxiOn419 wrote:Hmmm, that might be a little bit expensive and a daunting task for me. If thats what it needed I would probably be better off selling the motor and getting an RB25.

This may be a stupid question but what exaclty is a ringland and why does oil in the intake point to that being the problem? If someone could give me an overview of what happens inside the engine when you have bad ringlands that would be great, this whole engine swap process is a big learning experience for me.
the ringlands are a small area of your piston between your rings.. when they break it usaully puts a small hole in the side of your piston.. that causes oil to be sucked up into the cylinder then pushed out in to the intake and exhaust.. i know on my buddys rb20 it wouldnt smoke or pump the oil through it till the motor was warm...

AxiOn419
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fast_s13 wrote:the ringlands are a small area of your piston between your rings.. when they break it usaully puts a small hole in the side of your piston.. that causes oil to be sucked up into the cylinder then pushed out in to the intake and exhaust.. i know on my buddys rb20 it wouldnt smoke or pump the oil through it till the motor was warm...
I used this motor for 2 years straight without any major mechanical issues. Wouldnt the engine have seized up by this point? Up until the wreck the engine ran pretty strong and made no funny noises

AxiOn419
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fast_s13 wrote:the ringlands are a small area of your piston between your rings.. when they break it usaully puts a small hole in the side of your piston.. that causes oil to be sucked up into the cylinder then pushed out in to the intake and exhaust.. i know on my buddys rb20 it wouldnt smoke or pump the oil through it till the motor was warm...
I think I see the big picture now. So wouldnt my exhaust have been pooring out blueish smoke constantly in this case? It never did. There was a little bit of black smoke here and there but I wouldnt say anything way abnormal. I believe the car was running rich. The turbo compressor seals seem to make more sense, is there a way to check if I pull the turbo off?

Cpt_Impossible
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AxiOn419
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Right? I see your catchcan has a little air filter on top, where can i can a little catch can like that?

Thanks

Cpt_Impossible
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Yeah, that is correct.

http://www.roadraceengineering.com

It's a great DSM vendor buut only do order forms or over the phone which I found kind of odd... but all my friends with DSM's used to buy from them and that is where I got mine. Good People.

or, you could get one of the crappy ones like everyone else has with that chinsy little clear tube on the side that you know will be stained to hell in a month or so.

Darius
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hey cpt_impossible. does that line running from your valve cover to the intake manifold have some kind of ball check valve or pcv valve on it?

AxiOn419
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Darius wrote:hey cpt_impossible. does that line running from your valve cover to the intake manifold have some kind of ball check valve or pcv valve on it?
I am not trying to question your question but just for my own clarification.. the line running from the valve cover (the right side of the valve cover) does not run to the intake manifold but rather the oil catch can, right? Or does the catch can somehow connect to the intake manifold as well?

Also, after talking with some people, the more reasonable problem seems to be the turbo compressor seal. If the rings were bad, wouldnt the engine have ran like poo and smoked like crazy? Remember that I used this engine for 2 years prior to it sitting. There is oil in the intercooler and throughout the whole intake system. If this rings were the issue, wouldnt the oil have to travel through the cylinder then out the valve? That seems unlikely but again, I may not be understanding it fully, if I am wrong in my thinking please do correct me. So.. rings or turbo seals?

I am going to call a local turbo shop and ask what it costs to replace the seals as I would like to have it done professionally. Let me know what you guys think! Thanks
Modified by AxiOn419 at 7:36 AM 10/4/2007

Darius
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Right, in his setup the line from the right valve cover runs to the catch can and then he has a line running back from the can to the intake upstream of the turbo to pull vacuum on the valve covers. I'm just hoping there's a check valve of sorts between the manifold and left valve cover or he would be putting boost pressure into the crank case. Bad! I'm guessing that aluminum block has a check valve in it somewhere. I'm just not as familiar with the RB20.

AxiOn419
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Looks like the stock setup to me. Here is a picture of my engine before the wreck:



Looks the same as cpt_impossibles. I dont fully understand the scenario you explained as to why it is a bad thing but I take your word for it.

Would that little aluminum block attached to the side of the manifold be the check valve? The hose runs from that block to the valve cover

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blurrbosi
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just get a catch can! They come with instructions. megan makes em... $60, Greddy makes em... $100. There are several places that sell all kinds of sizes and shapes.

Cpt_Impossible
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My catch can system goes:

Intake manifoldIntake side valve coverExhaust side valve coverCatch can inCatch can outTurbo Intake recirculation pipe

There are no check valves or anything that I added... It still allows the crank cases to vent and not build up pressure while keeping the oil from flowing through the turbo, intercooler and all that other business you want to keep oil free inside.

AxiOn419
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Alright, so maybe a catch can is all I will need? I will definatly get one, do most people use one?

I checked that site, didnt see the can. What about this:

http://cgi.ebay.com/ebaymotors...ZWDVW


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