How to manage a bad case of blow by ...
How to manage a bad case of blow by ...
Well, after much reading it is fair to say that I'm not a happy camper.
I have a builtzmotors engine that I bought in August of 2006, since then I've only put about 17k miles on it. About a year ago (3k ish miles ago) it started smoking under decel, since then it's been a non-stop battle on figuring out a way to elimitate this smoke.
In a recent leakdown test we found the following :-
14%, 16%, 1, 2
20%, 22%, 3, 4
16%, 25%, 5, 6
Spark plugs look like this ..
I had my PCV hosing setup the same way that rcdash is successfully running but I was still getting smoke so I took out the PCV valve and made the following device, a 1/2" open plug replacement for the PCV.
I then proceeded to hook up vacuum source (from the plenum) to my catchcan and took it for a test drive. In the 4 miles it is from my house to work there was not a hint of smoke and I felt quite triumpant except which I checked under the hood and found that I have managed to suck about 1/2 quart of oil into the catch can.
At this point I have disconnected my source of vaccuum and am just venting both drivers and passenger side to atmosphere but I am still smoking under decel and according to a friend that was following me 'quite often'.
I guess my next step is to take off the driver's side valve cover and drill out the rear connection.
So I guess the few questions that I have are :-
1) Is anyone else having this kind of blow by and how are they managing it?
2) At this level of leakdown and with only 17k on the motor how long before I will need a new bottom end?
3) How can I apply vaccuum to the catchcan and NOT draw out such a massive amount of oil?
4) How the hell is it even drawing out that much oil in the first place?
5) Has anyone considered using an air/oil seperator and then feeding the excess oil back into the pan somehow?
On that last question, forge have a seperator for sale that might work ...
http://www.forgemotorsport.co.uk/con...roduct=FMOS070
Ninja edit: I have searched and read every PCV related post ...
Thoughts ???
I have a builtzmotors engine that I bought in August of 2006, since then I've only put about 17k miles on it. About a year ago (3k ish miles ago) it started smoking under decel, since then it's been a non-stop battle on figuring out a way to elimitate this smoke.
In a recent leakdown test we found the following :-
14%, 16%, 1, 2
20%, 22%, 3, 4
16%, 25%, 5, 6
Spark plugs look like this ..
I had my PCV hosing setup the same way that rcdash is successfully running but I was still getting smoke so I took out the PCV valve and made the following device, a 1/2" open plug replacement for the PCV.
I then proceeded to hook up vacuum source (from the plenum) to my catchcan and took it for a test drive. In the 4 miles it is from my house to work there was not a hint of smoke and I felt quite triumpant except which I checked under the hood and found that I have managed to suck about 1/2 quart of oil into the catch can.
At this point I have disconnected my source of vaccuum and am just venting both drivers and passenger side to atmosphere but I am still smoking under decel and according to a friend that was following me 'quite often'.
I guess my next step is to take off the driver's side valve cover and drill out the rear connection.
So I guess the few questions that I have are :-
1) Is anyone else having this kind of blow by and how are they managing it?
2) At this level of leakdown and with only 17k on the motor how long before I will need a new bottom end?
3) How can I apply vaccuum to the catchcan and NOT draw out such a massive amount of oil?
4) How the hell is it even drawing out that much oil in the first place?
5) Has anyone considered using an air/oil seperator and then feeding the excess oil back into the pan somehow?
On that last question, forge have a seperator for sale that might work ...
http://www.forgemotorsport.co.uk/con...roduct=FMOS070
Ninja edit: I have searched and read every PCV related post ...
Thoughts ???
Where is the smoke coming out of, crankcase or exhaust? I had this same experience and it was cranked ring lands (Back when I was learning how to tune, got careless a couple of times on my vq30). But mine was not at decel it was during acceleration and at idle, huge load of smoke would come out of the crankcase (both valvecovers).
So to understand more clearly you said you vented both valve covers, plugged the manifold, and still smoked?
So to understand more clearly you said you vented both valve covers, plugged the manifold, and still smoked?
Where is the smoke coming out of, crankcase or exhaust? I had this same experience and it was cranked ring lands (Back when I was learning how to tune, got careless a couple of times on my vq30). But mine was not at decel it was during acceleration and at idle, huge load of smoke would come out of the crankcase (both valvecovers).
So to understand more clearly you said you vented both valve covers, plugged the manifold, and still smoked?
So to understand more clearly you said you vented both valve covers, plugged the manifold, and still smoked?
Yes, vented both valve covers (although only passenger side has been opened up) and the manifold is plugged and still smoking ...
I'm wondering if because of how bad the blowby is on the driver's side (4 & 6), opening up the driver's port is gonna make a huge difference, I'm gonna tackled this once I get home ...
It shouldnt matter which side is vented, below the heads its all one area, so even if its just one cylinder you'll see smoke on both valve covers. Perhaps its valve seals? I would assume if it was bad case of blow by you will be getting smoke out the valve covers not the exhaust (although or both). you have zero smoke out the valve covers?
It shouldnt matter which side is vented, below the heads its all one area, so even if its just one cylinder you'll see smoke on both valve covers. Perhaps its valve seals? I would assume if it was bad case of blow by you will be getting smoke out the valve covers not the exhaust (although or both). you have zero smoke out the valve covers?
The smoke may be coming from the exhaust, but the spark plug valve cover seal is a thought - were any of the spark plugs covered in oil when removed? Didn't look like it.
If you have breathers on both valve covers and you are still smoking on decel, then there is a good chance you have residual oil in your intake system - did you clean out the manifold and charge piping (and maybe check the IC also)?
During my various experiments with hose routing, I managed to fill up my IC with oil on more than one occasion...
With the two breathers on there and a clean manifold/charge pipe/ic, you should NOT be smoking unless there is a turbo seal or valve stem seal issue...
If you have breathers on both valve covers and you are still smoking on decel, then there is a good chance you have residual oil in your intake system - did you clean out the manifold and charge piping (and maybe check the IC also)?
During my various experiments with hose routing, I managed to fill up my IC with oil on more than one occasion...
With the two breathers on there and a clean manifold/charge pipe/ic, you should NOT be smoking unless there is a turbo seal or valve stem seal issue...
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The smoke may be coming from the exhaust, but the spark plug valve cover seal is a thought - were any of the spark plugs covered in oil when removed? Didn't look like it.
If you have breathers on both valve covers and you are still smoking on decel, then there is a good chance you have residual oil in your intake system - did you clean out the manifold and charge piping (and maybe check the IC also)?
During my various experiments with hose routing, I managed to fill up my IC with oil on more than one occasion...
With the two breathers on there and a clean manifold/charge pipe/ic, you should NOT be smoking unless there is a turbo seal or valve stem seal issue...
If you have breathers on both valve covers and you are still smoking on decel, then there is a good chance you have residual oil in your intake system - did you clean out the manifold and charge piping (and maybe check the IC also)?
During my various experiments with hose routing, I managed to fill up my IC with oil on more than one occasion...
With the two breathers on there and a clean manifold/charge pipe/ic, you should NOT be smoking unless there is a turbo seal or valve stem seal issue...
Here is a pic of the lower plenum, apart from fuel residue it is as clean as anything ... I'm gonne take off the driver's side valve cover tonight and drill out the hole and then re-install everything then see what happens. As you say if I'm still smoking like this then something else is up ...
MrPharmD:
I have pretty much come to the conclusion that I need a new short block, I just want to limp through this summer if I can but if my smoking persists I will have no excuse but to garage the thing until I can get the work done to fix it.
So, anyone care to guess as to how much on average a shop will charge to swap a shortblock ???
pic of lower plenum :
The oil would be pooled under the center brass bracket if you've been using the manifold as a vacuum, but the rest looks pretty clean as far as I can tell from the pic. It's a shame to tear down a motor that's making good power - just gotta find out where that oil is coming from...
EDIT: one thing I notice is a hose coming off your rear driver's side port. Rather than going to all the trouble of drilling that out - try to just put the breather right on that nipple - no hose. Same thing on passenger side - keep all tubing real short or don't use any at all. It's possible that you are generating so much blow by that you are still building crankcase pressure and are spilling oil through the turbo seal I suppose. With the breather right on the nipple, it should help minimize that possibility.
EDIT: one thing I notice is a hose coming off your rear driver's side port. Rather than going to all the trouble of drilling that out - try to just put the breather right on that nipple - no hose. Same thing on passenger side - keep all tubing real short or don't use any at all. It's possible that you are generating so much blow by that you are still building crankcase pressure and are spilling oil through the turbo seal I suppose. With the breather right on the nipple, it should help minimize that possibility.
Last edited by rcdash; Jun 7, 2010 at 08:46 AM.
The oil would be pooled under the center brass bracket if you've been using the manifold as a vacuum, but the rest looks pretty clean as far as I can tell from the pic. It's a shame to tear down a motor that's making good power - just gotta find out where that oil is coming from...
EDIT: one thing I notice is a hose coming off your rear driver's side port. Rather than going to all the trouble of drilling that out - try to just put the breather right on that nipple - no hose. Same thing on passenger side - keep all tubing real short or don't use any at all. It's possible that you are generating so much blow by that you are still building crankcase pressure and are spilling oil through the turbo seal I suppose. With the breather right on the nipple, it should help minimize that possibility.
EDIT: one thing I notice is a hose coming off your rear driver's side port. Rather than going to all the trouble of drilling that out - try to just put the breather right on that nipple - no hose. Same thing on passenger side - keep all tubing real short or don't use any at all. It's possible that you are generating so much blow by that you are still building crankcase pressure and are spilling oil through the turbo seal I suppose. With the breather right on the nipple, it should help minimize that possibility.
Edit: I just found K&N part 62-1340 has 5/8" on a 2" filter, just bought 2 ...
Last edited by cersoft; Jun 7, 2010 at 09:16 AM.
If you've already got the valve covers off, then I would go ahead and drill out the driver's side port, put on new gaskets and then put the breathers right on the ports.
Once you get the smoking issue licked, you can work on a catch can set up if you really feel the need to...
Once you get the smoking issue licked, you can work on a catch can set up if you really feel the need to...
If you've already got the valve covers off, then I would go ahead and drill out the driver's side port, put on new gaskets and then put the breathers right on the ports.
Once you get the smoking issue licked, you can work on a catch can set up if you really feel the need to...
Once you get the smoking issue licked, you can work on a catch can set up if you really feel the need to...
Like you said, it would be a shame to tear down a motor that is making good power and it is definately still doing that. It's just really embarrasing smoke like it is ...
to confirm that the cylinder leakage is happening at the pistons, remove the oil cap and listen in there for the leaking air. its plain as day. also listen in the tailpipe to check exhaust valves (if you have a true dual make sure to listen at the bank you are testing), and intake valves you will hear through the throttle body.
edit; im sure you understood already but just to be clear this would only work WHILE doing the leakdown test LOL, just listening in there at any given time isnt going to work haha.
but since you are moving a lot of oil, its pretty much definately the pistons.
im in the same boat, im on 5 years on my short block. i dont know about you, but for me its no surprise since i am very mean to my engine. to go 5 years per short block is cool with me.... i guarentee any exotic with the same type of HP would have required MUCH MUCH more money in maintance then freshening up my pistons every 5 years!
my leakage isnt as bad as yours, ive got one at 18%, two at 15%, and the rest at 8% or below. I get no oil at all through my PCV system. I just burn during hot starts (and only hot starts, not a single puff on cold starts) at idle, and a decent enough puff at full throttle. I burned half a quart in 800 miles of mostly beating it.
send me over short block parts and maybe my machine shop will give us a discount for doing a pair
edit; im sure you understood already but just to be clear this would only work WHILE doing the leakdown test LOL, just listening in there at any given time isnt going to work haha.
but since you are moving a lot of oil, its pretty much definately the pistons.
im in the same boat, im on 5 years on my short block. i dont know about you, but for me its no surprise since i am very mean to my engine. to go 5 years per short block is cool with me.... i guarentee any exotic with the same type of HP would have required MUCH MUCH more money in maintance then freshening up my pistons every 5 years!
my leakage isnt as bad as yours, ive got one at 18%, two at 15%, and the rest at 8% or below. I get no oil at all through my PCV system. I just burn during hot starts (and only hot starts, not a single puff on cold starts) at idle, and a decent enough puff at full throttle. I burned half a quart in 800 miles of mostly beating it.
send me over short block parts and maybe my machine shop will give us a discount for doing a pair
Last edited by phunk; Jun 7, 2010 at 12:17 PM.
hey nice find on that cosworth oil seperator. it reminds me of what all the honda B,D, and H series motors have hiding under the intake manifold. Pretty sweet.
I have a nice oil seperator i never installed, but its just a catch tank. However, it would of course be no problem to simply drill and tap a fitting on the bottom to return it to the crank case just like this cosworth piece.
I have a nice oil seperator i never installed, but its just a catch tank. However, it would of course be no problem to simply drill and tap a fitting on the bottom to return it to the crank case just like this cosworth piece.
Pistons or piston rings, or both?
I'm just wondering because I just got a built engine and I do intend to beat on it, and I'm wondering what will need to be refreshed when it's time comes...
I'm just wondering because I just got a built engine and I do intend to beat on it, and I'm wondering what will need to be refreshed when it's time comes...
but since you are moving a lot of oil, its pretty much definately the pistons.
im in the same boat, im on 5 years on my short block. i dont know about you, but for me its no surprise since i am very mean to my engine. to go 5 years per short block is cool with me.... i guarentee any exotic with the same type of HP would have required MUCH MUCH more money in maintance then freshening up my pistons every 5 years!
im in the same boat, im on 5 years on my short block. i dont know about you, but for me its no surprise since i am very mean to my engine. to go 5 years per short block is cool with me.... i guarentee any exotic with the same type of HP would have required MUCH MUCH more money in maintance then freshening up my pistons every 5 years!
if a built motor is leaking down high through the pistons, most likely you have melted or cracked the ring lands on the pistons, and the rings no longer have proper support to seal correctly.
its not always a normal thing to have to expect to do, it depends on how much on the edge you tune it, how often you screw up and lean it out or run shitty gas etc etc... its just that the higher HP the more sensitive it will become. but if you go apeshit on being careful with it, you dont need to expect to replace pistons. ive built motors that are on 10 years no problems yet. im just not exactly very careful with my personal engine and keeping up with its state of tune. just last week i leaned it out REALLY bad from trying full throttle during a hard right turn on a low tank of gas. i know very well about the limitiations of the stock fuel tank in this car and how full throttle during a hard right at low tank level will likely starve you.
its not always a normal thing to have to expect to do, it depends on how much on the edge you tune it, how often you screw up and lean it out or run shitty gas etc etc... its just that the higher HP the more sensitive it will become. but if you go apeshit on being careful with it, you dont need to expect to replace pistons. ive built motors that are on 10 years no problems yet. im just not exactly very careful with my personal engine and keeping up with its state of tune. just last week i leaned it out REALLY bad from trying full throttle during a hard right turn on a low tank of gas. i know very well about the limitiations of the stock fuel tank in this car and how full throttle during a hard right at low tank level will likely starve you.
to confirm that the cylinder leakage is happening at the pistons, remove the oil cap and listen in there for the leaking air. its plain as day. also listen in the tailpipe to check exhaust valves (if you have a true dual make sure to listen at the bank you are testing), and intake valves you will hear through the throttle body.
edit; im sure you understood already but just to be clear this would only work WHILE doing the leakdown test LOL, just listening in there at any given time isnt going to work haha.
but since you are moving a lot of oil, its pretty much definately the pistons.
im in the same boat, im on 5 years on my short block. i dont know about you, but for me its no surprise since i am very mean to my engine. to go 5 years per short block is cool with me.... i guarentee any exotic with the same type of HP would have required MUCH MUCH more money in maintance then freshening up my pistons every 5 years!
my leakage isnt as bad as yours, ive got one at 18%, two at 15%, and the rest at 8% or below. I get no oil at all through my PCV system. I just burn during hot starts (and only hot starts, not a single puff on cold starts) at idle, and a decent enough puff at full throttle. I burned half a quart in 800 miles of mostly beating it.
send me over short block parts and maybe my machine shop will give us a discount for doing a pair
edit; im sure you understood already but just to be clear this would only work WHILE doing the leakdown test LOL, just listening in there at any given time isnt going to work haha.
but since you are moving a lot of oil, its pretty much definately the pistons.
im in the same boat, im on 5 years on my short block. i dont know about you, but for me its no surprise since i am very mean to my engine. to go 5 years per short block is cool with me.... i guarentee any exotic with the same type of HP would have required MUCH MUCH more money in maintance then freshening up my pistons every 5 years!
my leakage isnt as bad as yours, ive got one at 18%, two at 15%, and the rest at 8% or below. I get no oil at all through my PCV system. I just burn during hot starts (and only hot starts, not a single puff on cold starts) at idle, and a decent enough puff at full throttle. I burned half a quart in 800 miles of mostly beating it.
send me over short block parts and maybe my machine shop will give us a discount for doing a pair
How many miles have you done in that 5 years, like I said, I've only done 17k on this motor and it's pretty done and I don't beat on it anywhere near as much as you probably do.
Also, do you have an idea as to the pricing for a lower end refresh, my biggest concern here is what was found with other builtzmotors when taking them apart ... If the motor is coming out I might as well just get a new S1 short block from FP ...
sigh ....
VV That's exactly what happened to my stock block...burned ring land on 1 piston due to a faulty injector...back then running at about 400whp
Well, with the built engine I'm running around ~500whp so we'll see how it goes, I'll probably do at the very least an annual re-tune to make sure there are no leaness issues...but now I have a CJM Stage 0 so I can monitor fuel pressure for any issues
And when the built engines time come, maybe I'll be able to get away with just piston replacement, but at that labor cost a full shortbock replacement might be a more practical...
Well, with the built engine I'm running around ~500whp so we'll see how it goes, I'll probably do at the very least an annual re-tune to make sure there are no leaness issues...but now I have a CJM Stage 0 so I can monitor fuel pressure for any issues
And when the built engines time come, maybe I'll be able to get away with just piston replacement, but at that labor cost a full shortbock replacement might be a more practical...
if a built motor is leaking down high through the pistons, most likely you have melted or cracked the ring lands on the pistons, and the rings no longer have proper support to seal correctly.
its not always a normal thing to have to expect to do, it depends on how much on the edge you tune it, how often you screw up and lean it out or run shitty gas etc etc... its just that the higher HP the more sensitive it will become. but if you go apeshit on being careful with it, you dont need to expect to replace pistons. ive built motors that are on 10 years no problems yet. im just not exactly very careful with my personal engine and keeping up with its state of tune. just last week i leaned it out REALLY bad from trying full throttle during a hard right turn on a low tank of gas. i know very well about the limitiations of the stock fuel tank in this car and how full throttle during a hard right at low tank level will likely starve you.
its not always a normal thing to have to expect to do, it depends on how much on the edge you tune it, how often you screw up and lean it out or run shitty gas etc etc... its just that the higher HP the more sensitive it will become. but if you go apeshit on being careful with it, you dont need to expect to replace pistons. ive built motors that are on 10 years no problems yet. im just not exactly very careful with my personal engine and keeping up with its state of tune. just last week i leaned it out REALLY bad from trying full throttle during a hard right turn on a low tank of gas. i know very well about the limitiations of the stock fuel tank in this car and how full throttle during a hard right at low tank level will likely starve you.
if a built motor is leaking down high through the pistons, most likely you have melted or cracked the ring lands on the pistons, and the rings no longer have proper support to seal correctly.
its not always a normal thing to have to expect to do, it depends on how much on the edge you tune it, how often you screw up and lean it out or run shitty gas etc etc... its just that the higher HP the more sensitive it will become. but if you go apeshit on being careful with it, you dont need to expect to replace pistons. ive built motors that are on 10 years no problems yet. im just not exactly very careful with my personal engine and keeping up with its state of tune. just last week i leaned it out REALLY bad from trying full throttle during a hard right turn on a low tank of gas. i know very well about the limitiations of the stock fuel tank in this car and how full throttle during a hard right at low tank level will likely starve you.
its not always a normal thing to have to expect to do, it depends on how much on the edge you tune it, how often you screw up and lean it out or run shitty gas etc etc... its just that the higher HP the more sensitive it will become. but if you go apeshit on being careful with it, you dont need to expect to replace pistons. ive built motors that are on 10 years no problems yet. im just not exactly very careful with my personal engine and keeping up with its state of tune. just last week i leaned it out REALLY bad from trying full throttle during a hard right turn on a low tank of gas. i know very well about the limitiations of the stock fuel tank in this car and how full throttle during a hard right at low tank level will likely starve you.
I have Arias ED's and my engine has pretty much always lived on the safely rich side of perfect, and I never get on it without at least 1/4 tank of gas