smoke at cold idle
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TECH Apprentice
Joined: Apr 2013
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From: eastern nc
smoke at cold idle engine fresh .after local machine shop screwed me over.problem At cold start up smokes after idling for 3 minutes smokes out of tail pipe .UNLESS AT start up I bring idle up to1800-2000 til engine temperature reach 180 then no smoke .afr open loop 13.2-13.6 ,number 6 feed to turbo no restrictor,number 10 drain .both valve covers vented with filters. suggestion any one?
Originally Posted by Redbull87
Why no oil feed restrictor? I would think you would need one on it.
What turbo? Did you measure the drain ID?What's likely happening is a poor flowing drain. Can you take a pic? How far is the drop from turbo to pan? You are probably right at the ragged edge of what the drain will flow and it backing up when it's cold and makin its way past the ring seals. I would either step up to a -12 drain and or take any bends/90's etc. out of the line.
Thread Starter
TECH Apprentice
Joined: Apr 2013
Posts: 367
Likes: 4
From: eastern nc
What turbo? Did you measure the drain ID?What's likely happening is a poor flowing drain. Can you take a pic? How far is the drop from turbo to pan? You are probably right at the ragged edge of what the drain will flow and it backing up when it's cold and makin its way past the ring seals. I would either step up to a -12 drain and or take any bends/90's etc. out of the line.
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Just asking in regard to a freshly built motor when I was turbo shopping and asking about when to use a restrictor or not a common answer I was getting on ls motors were to more likely use a restrictor depending on the oil pump being stock or a high pressure or high volume pump.Aside from what you mentioned already in regards to oil drain having the easiest path back to the pan etc. When my original drain was routed and had a 90* fitting and a slight kink in the line,also didnt have a restrictor.The car smoked lightly at idle..smoke screen underload.
Naturally I asked for help from the vendor and on here and was given the same advice about triple checking my drain line.The vendor advised me to verfiy my oil pressure at cold idle and hot idle and wot and report back. I do have a melling hv pump. Found the kink in my drain line and it reduced alot of smoke.Was told to run a restrictor that was supplied with the turbo and havent had an issue since.
Many guys dont use them Im well aware,but alot of them that Ive seen are using scavenge pumps also and much larger turbos than my lil 78mm.
For his symptom of only smoking at cold idle doesnt quite appear to be a lack of drainage.Im still new to having a turbo car(2yrs) and still learning.This is just what I experienced and what was told to me by the vendor and quite a few other ls builders I trust.
Naturally I asked for help from the vendor and on here and was given the same advice about triple checking my drain line.The vendor advised me to verfiy my oil pressure at cold idle and hot idle and wot and report back. I do have a melling hv pump. Found the kink in my drain line and it reduced alot of smoke.Was told to run a restrictor that was supplied with the turbo and havent had an issue since.
Many guys dont use them Im well aware,but alot of them that Ive seen are using scavenge pumps also and much larger turbos than my lil 78mm.
For his symptom of only smoking at cold idle doesnt quite appear to be a lack of drainage.Im still new to having a turbo car(2yrs) and still learning.This is just what I experienced and what was told to me by the vendor and quite a few other ls builders I trust.
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Verdad Gallardo What are you taking about? Cold idle smoking and poor drainage go hand in hand.. You shouldn't listen to anyone besides the turbo manufacturers. I don't care what a vendor told you or some LS "expert" You will be extremely hard pressed to find a JB turbo manufacturer that will tell you to stick a restrictor in line. Most of the time a restrictor in a JB is a band aid and is doing nothing more than hiding the real issue.
Further more the comment about the majority of non restricted JB turbo guys using scavenge pumps is no where near the truth. Where do you guys come up with this crap?
Proper Turbo drain setup is not rocket science.. But you have to know how to do it. No kinks, minimize bends, make sure you have a decent drop, make sure your outlet (if in pan) is above resting oil line and most importantly make sure you're ID of the drain on the turbo matches the ID of your drain line.. Cover these bases and I bet your car doesn't smoke at all, ever.
Further more the comment about the majority of non restricted JB turbo guys using scavenge pumps is no where near the truth. Where do you guys come up with this crap?
Proper Turbo drain setup is not rocket science.. But you have to know how to do it. No kinks, minimize bends, make sure you have a decent drop, make sure your outlet (if in pan) is above resting oil line and most importantly make sure you're ID of the drain on the turbo matches the ID of your drain line.. Cover these bases and I bet your car doesn't smoke at all, ever.
Last edited by oscs; Aug 18, 2016 at 08:12 AM.
I never said majority of guys with a jb turbo run pumps. I said what Ive seen around here are guys with much larger turbos than mine are using pumps without a restrictor. The vendor..manufacturer and my tuner all said to run a restrictor. I didnt make it up for ***** n giggles. Ill quote it directly from On3 site if you like.In my case I followed their advice and my issue was solved.
From On3:
If you are running one of the On 3 Performance Ceramic Ball Bearing turbochargers and do not have a restrictor, this is absolutely required. If you run a standard -3 or -4 feed up to the turbo, you will most likely start seeing oil in the compressor or smoke under boost coming out of the tail pipes. This is our restrictor fitting which cuts the oil volume down to what the turbo requires to operate.
Some customers running the On 3 Performance Journal turbochargers also may possibly require this with high volume oil pumps. In most cases where you are seeing around 60psi or more under load, you might consider running this if you are getting any oil passing through the seal. Often times on the GM LSX based platforms, we run these even on the journal bearing turbochargers due to the engine oil pressure.
From On3:
If you are running one of the On 3 Performance Ceramic Ball Bearing turbochargers and do not have a restrictor, this is absolutely required. If you run a standard -3 or -4 feed up to the turbo, you will most likely start seeing oil in the compressor or smoke under boost coming out of the tail pipes. This is our restrictor fitting which cuts the oil volume down to what the turbo requires to operate.
Some customers running the On 3 Performance Journal turbochargers also may possibly require this with high volume oil pumps. In most cases where you are seeing around 60psi or more under load, you might consider running this if you are getting any oil passing through the seal. Often times on the GM LSX based platforms, we run these even on the journal bearing turbochargers due to the engine oil pressure.
I never said majority of guys with a jb turbo run pumps. I said what Ive seen around here are guys with much larger turbos than mine are using pumps without a restrictor. The vendor..manufacturer and my tuner all said to run a restrictor. I didnt make it up for ***** n giggles. Ill quote it directly from On3 site if you like.In my case I followed their advice and my issue was solved.
Of course you did because you put a band aid on it like they asked.. Did you go through all the proper checks like I mentioned earlier? Did they ask where your drains entered the system? height of turbos in comparison to the pan etc? Did your experts ask you about turbo drain angle degree? did they know the ID of the drain size and have you verify it or did they just tell you to slap a restrictor on it and move along
From On3:
If you are running one of the On 3 Performance Ceramic Ball Bearing turbochargers and do not have a restrictor, this is absolutely required. If you run a standard -3 or -4 feed up to the turbo, you will most likely start seeing oil in the compressor or smoke under boost coming out of the tail pipes. This is our restrictor fitting which cuts the oil volume down to what the turbo requires to operate.
Irrelevant to this argument
Some customers running the On 3 Performance Journal turbochargers also may possibly require this with high volume oil pumps. In most cases where you are seeing around 60psi or more under load, you might consider running this if you are getting any oil passing through the seal. Often times on the GM LSX based platforms, we run these even on the journal bearing turbochargers due to the engine oil pressure.
Of course you did because you put a band aid on it like they asked.. Did you go through all the proper checks like I mentioned earlier? Did they ask where your drains entered the system? height of turbos in comparison to the pan etc? Did your experts ask you about turbo drain angle degree? did they know the ID of the drain size and have you verify it or did they just tell you to slap a restrictor on it and move along
From On3:
If you are running one of the On 3 Performance Ceramic Ball Bearing turbochargers and do not have a restrictor, this is absolutely required. If you run a standard -3 or -4 feed up to the turbo, you will most likely start seeing oil in the compressor or smoke under boost coming out of the tail pipes. This is our restrictor fitting which cuts the oil volume down to what the turbo requires to operate.
Irrelevant to this argument
Some customers running the On 3 Performance Journal turbochargers also may possibly require this with high volume oil pumps. In most cases where you are seeing around 60psi or more under load, you might consider running this if you are getting any oil passing through the seal. Often times on the GM LSX based platforms, we run these even on the journal bearing turbochargers due to the engine oil pressure.
This last one makes me laugh from a good hardy place. 60 PSI is high oil pressure?
I get that you're just doing what the manufacturer says "may" be correct but this is a load of ****. 60 PSI is LOW compared to some of the applications ive seen. On3 has once again proven to me that they are a sub par turbo manufacturer. With that said in some actual circumstances a resitrictor can be used on JB turbos. I believe Garret has recommended the use of one in a few situations but its rare. JB turbos love oil. Don't you find it odd that in cases with the same turbo some people have issues with oil blowing past the seals and others don't? Do you honestly think that has to do with the turbo it self or the 900 other things application related that the user could have screwed up like using china AN fittings when under sized ports.
My last twin turbo car had the knarliest meling pump you can get and i never had a single issue. I've read countless threads where people with the exact same setup where struggling with smoke.. Its all in the setup man.
Last edited by oscs; Aug 18, 2016 at 10:06 AM.
By all means Im not saying you are right or wrong or discrediting your engine building/racing experience.Just stating what I have come across..what I was told and by who.The steps Ive taken and so far I havent had an issue for me to say they steered me wrong at this point. As I said Im still learning also, Now i fully agree on having a proper drain. I had to clock mine and check the angle and found a much easier path to drain into the front timing cover. Which helped alot.Well I wouldnt go around saying On3 are on the level of other manufacturers of much better quality units lol.Just a budget chinese turbo alternative lol.Im not expecting the world from my turbo for what it cost me 
Now you said earlier about cold idle and smoking out the turbo goes hand in hand,care to explain more about it? Want to understand why it wouldnt be a constant smoke machine even when the oil is hot or at higher rpms it clear out. Is oil pooling up from lack of drainage at the turbo more as its cold and idling,then once its up to temp and flows easier his issue fades away?
Now you said earlier about cold idle and smoking out the turbo goes hand in hand,care to explain more about it? Want to understand why it wouldnt be a constant smoke machine even when the oil is hot or at higher rpms it clear out. Is oil pooling up from lack of drainage at the turbo more as its cold and idling,then once its up to temp and flows easier his issue fades away?
By all means Im not saying you are right or wrong or discrediting your engine building/racing experience.Just stating what I have come across..what I was told and by who.The steps Ive taken and so far I havent had an issue for me to say they steered me wrong at this point. As I said Im still learning also, Now i fully agree on having a proper drain. I had to clock mine and check the angle and found a much easier path to drain into the front timing cover. Which helped alot.Well I wouldnt go around saying On3 are on the level of other manufacturers of much better quality units lol.Just a budget chinese turbo alternative lol.Im not expecting the world from my turbo for what it cost me
Now you said earlier about cold idle and smoking out the turbo goes hand in hand,care to explain more about it? Want to understand why it wouldnt be a constant smoke machine even when the oil is hot or at higher rpms it clear out. Is oil pooling up from lack of drainage at the turbo more as its cold and idling,then once its up to temp and flows easier his issue fades away?
Now you said earlier about cold idle and smoking out the turbo goes hand in hand,care to explain more about it? Want to understand why it wouldnt be a constant smoke machine even when the oil is hot or at higher rpms it clear out. Is oil pooling up from lack of drainage at the turbo more as its cold and idling,then once its up to temp and flows easier his issue fades away?
Last edited by oscs; Aug 18, 2016 at 10:27 AM.
Ok got it, now if his issues were different as you said putting a bandaid on masking other problems and smoking underload would his original thought of pcv or worse..piston rings be a more likely culprit?
If he went through all the proper checks such as Drain angle, length of drain, outlet position, degree angle of turbo, drain size etc. Than yes it very well could be a major issue like excessive blow by. That could be checked very easily though. However i would say that is unlikely as he mentioned it clears up under load.
Common cold start non turbo application points to valve seals, which one some engines might be installed upside down or incorrect types used.
On a turbo engine, you can easily tell if the turbo is the cause for the smoke, inspect the inside of the downpipe near the turbine... there will be oil all over it during a cold start, still slightly sticky/liquid. I would let the engine run a few seconds to get the oil to appear then inspect the downpipe inside. Or simply attack the drain whichever is easier.
CLearing up under load is a misnomer. For starters, it might not be cleared up completely, but simply masked by the engines output. In other words, during load there is much more pressure and temperature in the exhaust system, which could mask a little bit of oil/smoke if it is minimal. That is why I say to check when the downpipe is still cold, after a slight cold start, to make sure you catch any liquid oil seeping from the turbine side. It is this viscous additive nature of warming oil (not yet hot enough to fully smoke clean) you are looking for that can 'disappear' when the downpipe heats up fully.
On a turbo engine, you can easily tell if the turbo is the cause for the smoke, inspect the inside of the downpipe near the turbine... there will be oil all over it during a cold start, still slightly sticky/liquid. I would let the engine run a few seconds to get the oil to appear then inspect the downpipe inside. Or simply attack the drain whichever is easier.
CLearing up under load is a misnomer. For starters, it might not be cleared up completely, but simply masked by the engines output. In other words, during load there is much more pressure and temperature in the exhaust system, which could mask a little bit of oil/smoke if it is minimal. That is why I say to check when the downpipe is still cold, after a slight cold start, to make sure you catch any liquid oil seeping from the turbine side. It is this viscous additive nature of warming oil (not yet hot enough to fully smoke clean) you are looking for that can 'disappear' when the downpipe heats up fully.
As said, valve guides can cause smoke at idle besides the turbo, and the PCV system.
I found my LS 6 valley cover was causing a problem on mine-oil was being sucked thru the valley PCV and into my 90 deg adapter, where I pick up vac.
I moved the PCV to the valve cover, and added an oil sep.
You just have to find out whats causing it
I found my LS 6 valley cover was causing a problem on mine-oil was being sucked thru the valley PCV and into my 90 deg adapter, where I pick up vac.
I moved the PCV to the valve cover, and added an oil sep.
You just have to find out whats causing it
One thing to consider in regards to valve seals being shot or installed wrong. He said it only does it on cold start up. If the seals were not functioning properly it would get worse or at least continue when it comes up to temp. The problem is elsewhere IMO. The guy needs to spend some time and look.
Thread Starter
TECH Apprentice
Joined: Apr 2013
Posts: 367
Likes: 4
From: eastern nc
findings inside diameter of drain 5/8 but bulkhead fitting at oil pan inside diameter is 1/2 ,also when I disconnected drain ,half of quart of oil ran out .drain might be to low.
Last edited by tim wellington; Aug 19, 2016 at 12:52 AM. Reason: words
Thread Starter
TECH Apprentice
Joined: Apr 2013
Posts: 367
Likes: 4
From: eastern nc
pcv help I hooked my pcv back to factory spot .smoking stop. but cant leave that way. because of boost . Again can some post there pcv routing with check valve and canister in stall