Oil and piston problem on built motor...

[Maglin]

I've recenntly learned how happens when you take the PCV system out of vacuum. Oil consumption is one of the systems but usually not anything this high. Mainly it's worst effect is sludge build-up and a dirtier engine. IE the burnt oil build up on all the engines walls. I've been running with no PCV system for little over a year and my oil consumption problem was very minimal. I 'm planning on using a vacuum pump on my crankcase for PCV operation this next time around.

It's possible that the crank pressure is enough to unseat the oil control rings and allow oil to pass this ring instead of the scrappers pushing it down to the bottom of the cylinder. Will crank vacuum the oil control rings are actually sucked to the cylinder walls thus doing a better job of oil control. Their are numerous benifits to running a vacuum pump crank case ventilation system. Their is a GM pump used on a lot of older caddy's that works pretty well. It doesn't provide to much vacuum but enough to allow a vacuum at high RPMS. Might want to think about giving it a try. Should be able to get one cheap at a salvage yard.

 

[tsunari]

A question:

When your head was built, did you get bronze valve guides put in? Or were they bronze inserts/liners?

 

[Enraged78]

A question:

When your head was built, did you get bronze valve guides put in? Or were they bronze inserts/liners?

I had bronze valve guides put in, as well as OEM valve seals and cut valves.

Matt.

 

[Enraged78]

I've recenntly learned how happens when you take the PCV system out of vacuum. Oil consumption is one of the systems but usually not anything this high. Mainly it's worst effect is sludge build-up and a dirtier engine. IE the burnt oil build up on all the engines walls. I've been running with no PCV system for little over a year and my oil consumption problem was very minimal. I 'm planning on using a vacuum pump on my crankcase for PCV operation this next time around.

It's possible that the crank pressure is enough to unseat the oil control rings and allow oil to pass this ring instead of the scrappers pushing it down to the bottom of the cylinder. Will crank vacuum the oil control rings are actually sucked to the cylinder walls thus doing a better job of oil control. Their are numerous benifits to running a vacuum pump crank case ventilation system. Their is a GM pump used on a lot of older caddy's that works pretty well. It doesn't provide to much vacuum but enough to allow a vacuum at high RPMS. Might want to think about giving it a try. Should be able to get one cheap at a salvage yard.

I think this is a very good idea. The V8 guys have been using vacuum pumps for years with great benefits. th 4G63 has pretty poor crank ventilation as it is, maybe a vacuum pump is really the cure here. Not to mention the power and gas mileage you pick up when the crankcase is under vacuum.

Matt.

 

[tsunari]

I had bronze valve guides put in, as well as OEM valve seals and cut valves.

Matt.

Alright, cause I had guide inserts/sleeves put in mine . . . there goes my idea . . .

 

[Enraged78]

Update:

I pulled the head off the car last night, and found a few wierd things.

First, there is NO gouge on any of the piston tops. I have no idea what I saw a few weeks ago when I looked down the spark plug hole into the combustion chamber, but these pistons are absolutely perfect. It may have been a funny reflection, or possibly a piece of carbon broke off, exposing the piston and making it look gouged. Either way, the pistons look great. Crosshatch pattern is still perfect, no bad lines on the cylinder walls. In addition to the oil deposits, there is a little bit of carbon on the piston tops, but not too much. there are quite a few places where the carbon is actually burning off. I attribute this to the water/alch injection, which seems to be working well.

Second, there is oil on TOP of my top ring of all four pistons. This tells me that the oil leak is coming from the head, and not the bottom end (please tell me if you disagree with this assesment). The pistons showed signs of oil burning inside the combustion chamber.

Third, 6 of my 8 intake valves were wet. Really wet. One was partially open and had oil covering the entire opening. The top of the head showed oil marks all around every intake valve. Exhaust valves looked better, but not great.

Fourth, I had oil deposits in my intake manifold where the manifold bolts to the head, and only there. The plenum was dry and oil-free. It almost looks like oil dripped into the intake manifold after the car was shut off. Wierd.

Anyway, here's what I'm doing to the head. I'm having it checked by a third party shop. This same shop found a crack in the #3 runner of my last head, which drove me nuts for a while. The shop that built the head is willing to stand behind their work, but I want a reputable independant third party to check it first, just so I know exactly what I'm dealing with. Once I know more about the head, I'll post it.

I'm considering replacing my oil control rings anyway, just to be safe. What do you guys think? Overkill? Bad idea in general?

Thanks,
Matt

 

[tsunari]

Update:
. . . I'm considering replacing my oil control rings anyway, just to be safe. What do you guys think? Overkill? Bad idea in general?

Thanks,
Matt

Interesting finds indeed . . . I realize that if one were to replace the oil rings, now would be the time to do it, but I think personally I would hold off and see what the the status of the head is. With all of the methodical work that has been put into troubleshooting this issue on both of our parts, it would seem a bit of a waste to go and change a few things up all at once and not know what the true source of the problem was. In the same breath, I would not want you to have to pull the head yet again, to just replace the rings . . .

Would it be feasable to pull the pistons out and check the condition of the rings? Check for damage, etc . . . I guess with the head off, you're a half-step away from doing that anyways.

On another thought . . . if you were to replace the oil rings, would that require re-honing the cylinder walls? Perhaps with a ball hone?

 

[Enraged78]

Interesting finds indeed . . . I realize that if one were to replace the oil rings, now would be the time to do it, but I think personally I would hold off and see what the the status of the head is. With all of the methodical work that has been put into troubleshooting this issue on both of our parts, it would seem a bit of a waste to go and change a few things up all at once and not know what the true source of the problem was. In the same breath, I would not want you to have to pull the head yet again, to just replace the rings . . .

Would it be feasable to pull the pistons out and check the condition of the rings? Check for damage, etc . . . I guess with the head off, you're a half-step away from doing that anyways.

On another thought . . . if you were to replace the oil rings, would that require re-honing the cylinder walls? Perhaps with a ball hone?

This is exactly the set of demons I've been wrestling with. If I've learned anything from these last two years of my informal education, it's that you shouldn't change more than one variable when trying to troubleshoot any problem. Replacing the rings as well as the head would introduce a new set of variables, and it would be impossible to tell which was really the culprit here. I think I will heed your advice and just wait for the machine shop to let me know the status of the head. With the oil marks as prominant as they are, and the valves of a 3K mile head as bad as they are, I think my best option is just to wait and see. Upon looking at the head, you'd think it was obvious that it is the root cause of my problems, especially considering I never burned any oil before I swapped this head on. However, the 1,000 miles I was running with elevated crankcase pressure may have offset that. Is 1,000 miles of high crankcase pressure enough to unseat an oil control ring?

As far as the oil control rings go, I shouldn't have to re-hone when it was just done 10K ago and considering the fact that oil control rings have the least amount of tension exterting outward toward the cylinder walls. However, ring seating is a very delicate balance, and I'm worried that replacing the oil control rings may cause another problem that I have not even contemplated.

As of right now, I think that waiting for the head diagnosis is the best idea. I'll post when I know more.

Thanks,
Matt.

 

[Maglin]

Matt,
Hey glad to see that it does appear to be the head. Usually the exhaust won't have oil on them as they run very very hot. The intake valves are cooled by the intake charge considerably and the oil won't burn right off it and thus you see what you are seeing now.

As for pulling pistons. I would highly recomend you don't. For a few reasons. Even with a torque plate hone your cylinders start to go out of round from the high dynamic compression that a turbo engine sees. The rings will form to the cylinder wall and kept it's seal. If you pull the pistons the rings will all turn and you can't install them with the same end gap arangment as they where when you pulled them. Now your rings won't seal as efficently as they were. And as for replacing any ring on a motor with over 50 miles on it is not advised without a new hone. And the oil control ring is one of the most important rings that is often never thought about. It does have the least tension on the scrapers and thus would be a nightmare to reseat if you where to change them after the initial break in. Then you might end up with an oil consumpiton nightmare and definitly be cursing yourself out over it.

If you want to go with spiffy valve guides Ferrea sells copper exhaust valve guides and bronze intake valve guides. They are not to expensive and if the shop knows what they are doing should be no problem to install. You would have to recut your valve seats with new guides but it's mainly just a freshing as the valve placement will most likely change and not seal correctly. I'm going to go with the copper/bronze valve guide arangment with my new head.

It would also be a good idea to put a oil press gauge on the port at the back of the head where the 1G stock oil feed is. You might not be seeing very much pressure and cause of that toasted your valve guides and most likely valves as well. I put an electric oil sending unit on that port and just used a on-on toggle switch to change between my oil filter housing and head oil pressure as to still only have one oil press gauge in the car. (I personally hate gagues as people think you are either rice or fast if you have a ton of them. I don't want people thinking either when they see my car.) Thanks for kepting us posted on whats going on.

 

[steel_3d]

It would also be a good idea to put a oil press gauge on the port at the back of the head where the 1G stock oil feed is. You might not be seeing very much pressure and cause of that toasted your valve guides and most likely valves as well.

Actually I'm pretty sure the valve stems or guides are never supposed to see oil, never mind oil pressure. You'd be burning oil constantly if that was the case. That's what seals are for, to keep oil on one side.

But it is likely that the valve guides are screwed since that's the only likely way the seals would have died so soon, which is the only way oil can get to the top of the valve (unless it's coming through the intake, which you should be able to see elsewhere in the intake tract).

Also, I don't believe in rehoning cylinders after such a short time. Some people suggest not even honing after hundreds of thousands of miles. You still have a good crosshatch. Honing will just add rough peaks to that, which the rings shave off quickly and it just becomes shavings in your oil. Most performance hone jobs include a "plateau hone" step that takes off these peaks and provides a finish that's closer to an already broken-in cylinder. This is to save the rings from unnecessary initial wear.

 

[Enraged78]

Matt,
Hey glad to see that it does appear to be the head. Usually the exhaust won't have oil on them as they run very very hot. The intake valves are cooled by the intake charge considerably and the oil won't burn right off it and thus you see what you are seeing now.

...

If you want to go with spiffy valve guides ...

...

It would also be a good idea to put a oil press gauge on the port at the back of the head where the 1G stock oil feed is....

Jer,

Thanks for the reply. I'm starting to lean in your direction when it comes to pulling the pistons. I'm just going to leave well enough alone, unless my engine builder is REALLY adament about pulling them for one reason or another. From the way I see it, the worst case scenario here is that I have to pull the head again to replace the rings, in which case I'd need a hone anyway, and for that, I'd pull the motor to have it done right. Bottle-brush honers are good in their own right, but I'd rather have a honing machine do it if I had to.

As far as the valve guides go, if I find that they're bad, I'll replace them. Ferrea makes some great stuff, so I might go that way if I have to. It's just more cheap insurance.

In regards to oil pressure, I have a 1g head on a 7-bolt block and my balance shafts blocked off. I have more oil pressure than I know what to do with. I have so much that I actually went back to the head feed for my turbo because the flow from my Evo III oil filter housing was just too much. I tested oil drain flow from both locations, and the pressure from both was way beyond stock, so I have my Evo III fed from the head. Mitsu uses this setup on the Evo III, which came with my turbo, so if it's good enough for them, it's good enough for me. As a result, I strongly doubt that my head problems were from lack of oil pressure. If it were, I would have killed my Evo III already, as the turbo is much more suspect to low pressure, and the turbo is fed after the head is. My gauge is almost always 1/4" from the high pressure mark. I will wind up installing a real gauge at some point, but I really don't have a place to mount it. Like you, I don't like attracting attention, so I ditched my A-pillar triple pod for a dual cluster dash kit, which is filled up right now.

Thanks,
Matt.

 

[Enraged78]

Actually I'm pretty sure the valve stems or guides are never supposed to see oil, never mind oil pressure. You'd be burning oil constantly if that was the case. That's what seals are for, to keep oil on one side.

But it is likely that the valve guides are screwed since that's the only likely way the seals would have died so soon, which is the only way oil can get to the top of the valve (unless it's coming through the intake, which you should be able to see elsewhere in the intake tract).

Also, I don't believe in rehoning cylinders after such a short time. Some people suggest not even honing after hundreds of thousands of miles. You still have a good crosshatch. Honing will just add rough peaks to that, which the rings shave off quickly and it just becomes shavings in your oil. Most performance hone jobs include a "plateau hone" step that takes off these peaks and provides a finish that's closer to an already broken-in cylinder. This is to save the rings from unnecessary initial wear.

Interesting post. Makes a lot of sense. With a plateau hone, the end result is something that works like a serrated knife. You still have your crosshatch pattern, but the peaks are wide and smooth, which serves to keep the rings alive longer. I imagine that this would also be good for oil control and ring seating, as the crosshatch will direct the ring's natural center within the cylinder bore.

I'm really thinking you're correct about the valve guides being fubar. The only other rational explanation I can come up with is that the seals may have just been installed incorrectly, or the head builder got lazy and left the old valve guides in. Either way, I'll have an answer from the second head shop pretty soon.

Thanks,
Matt.

 

[Maglin]

Actually I'm pretty sure the valve stems or guides are never supposed to see oil, never mind oil pressure. You'd be burning oil constantly if that was the case. That's what seals are for, to keep oil on one side.

But it is likely that the valve guides are screwed since that's the only likely way the seals would have died so soon, which is the only way oil can get to the top of the valve (unless it's coming through the intake, which you should be able to see elsewhere in the intake tract).

Also, I don't believe in rehoning cylinders after such a short time. Some people suggest not even honing after hundreds of thousands of miles. You still have a good crosshatch. Honing will just add rough peaks to that, which the rings shave off quickly and it just becomes shavings in your oil. Most performance hone jobs include a "plateau hone" step that takes off these peaks and provides a finish that's closer to an already broken-in cylinder. This is to save the rings from unnecessary initial wear.

Yes the guides don't see oil. I was more or less leaning in the direction that no to little oil in the head would allow the valve guides to overheat. It might not be anything but it was what I was thinking.

As for the hone job I disagree. Those peaks you speak about are what wear/break-in the rings to the cylinder. Their is a reason why rings that don't seat don't seal. They have to be worn to the cylinders. And that is because the rings are definitly not going to be a perfect circle once they are in the bores they will be compressed and not true round. So it wears into the shape of the given cylinder. The cylinder will loose the ridges very quickly. The OEMs don't use anything special on their motors when they build them and they can go for 200K+ miles these days. I'm not to sure if I've ever seen anything aftermarket last that long. The only reason I go with moly rings over cast is because they are stronger and are less likly to crack for high heat and pressures. Not cause they will last any longer. I don't expect any HO motor I build to go longer than 50K miles before I'm into it again. That is because I drive everything I own like it stole it and that has it's price in more maintance.

I'm not going to say a platue hone is bad or good. I wouldn't do it. I see it as gimicky and just something for a machine shop to sell you. And is their any proof that this they are even doing what they are selling? Most machine shops don't want to pay for motors. So they usually overbore as to not make any of their motors tight. That kepts them from buying their customers new pistons if they get scored. I really don't see them making a all ready broken in cylinder wall that is less likely to seat the rings. They they are having to rehone and buy new rings. I'm not flaming you. Just supporting my opinion on engine break-in and build up. I firmly believe in a full power break-in N/A. Boosted I wouldn't want to go over 10 PSI if you can.

And one last thing to think about. You said you have very very high oil pressure. That is very very bad. Not only for seals but your motor as well. With high oil pressure you are going to have unfiltered oil in your engine. Because your oil system has a oil bypass valve that will bypass the oil filter if oil pressure gets past a certain point. OEMs do this so a plugged up oil filter won't kill the oil system. On engine break-in with high oil pressure a lot of the metal shavings just kept going through the oiling system. That is why a lot of turbo's die on break-in. 10 PSI of oil pressure per 1000 RPM is a very good rule of thumb. That isn't my opinion. That is fact. Enlarge your pressure valve opening to get your oil press where it needs to be. Mine is almost 2x as large as stock and I have almost perfect oil pressure. No Balance shafts. Was going to remove the squirters but I don't want 150 PSI of oil pressure at 9000 RPMS so I left them in.

 

[TSIfreek]

Good post above all good info. I agree as well with your Idea to ring sealing. I think the platue hone is there for less wear on the rings when the engine is first started but I also agree you may have a better oil controlled engine without it since the rings and walls will wear together to give a greater seal? Depending on the rings used I guess also has somthing to do with how smooth the walls should be. Moly rings are just Iron rings coated with moly.

 

[Enraged78]

Yes the guides don't see oil. I was more or less leaning in the direction that no to little oil in the head would allow the valve guides to overheat. It might not be anything but it was what I was thinking.

I'm not going to say a platue hone is bad or good....

...

And one last thing to think about. You said you have very very high oil pressure. That is very very bad. Not only for seals but your motor as well. With high oil pressure you are going to have unfiltered oil in your engine. Because your oil system has a oil bypass valve that will bypass the oil filter if oil pressure gets past a certain point. OEMs do this so a plugged up oil filter won't kill the oil system. On engine break-in with high oil pressure a lot of the metal shavings just kept going through the oiling system. That is why a lot of turbo's die on break-in. 10 PSI of oil pressure per 1000 RPM is a very good rule of thumb. That isn't my opinion. That is fact. Enlarge your pressure valve opening to get your oil press where it needs to be. Mine is almost 2x as large as stock and I have almost perfect oil pressure. No Balance shafts. Was going to remove the squirters but I don't want 150 PSI of oil pressure at 9000 RPMS so I left them in.

I don't have a plateau hone, so it shouldn't be an issue with my motor. Interesting post, either way.

As far as oil pressure goes, I have an Evo III oil housing, which has a slightly larger relief port than the 2G housing. I compared the two when I swapped it over, and it was definately bigger. I don't know how this compares to a 1G. I don't have a 'real' pressure gauge right now, and I'm not about to port the housing without knowing what my true pressure is. In the event that I get one, and have time to pull the timing side apart, port the hole, and repeating this process until I get the oil pressure I want, I'll post my results. I can definately say that I don't have that kind of time right now, and the motor is apart right now anyway.

Just out of curiosity, what kind of oil pressure are you seeing at idle and load? What about when the bypass valve opens?

I know that both too much and too little oil pressure are really bad for a motor, and I have heard the 10PSI per 1000 rule before. We know that I definately don't have a shortage of oil pressure, but too much might be an issue here too.

Matt.

 

[steel_3d]

As for the hone job I disagree. Those peaks you speak about are what wear/break-in the rings to the cylinder. Their is a reason why rings that don't seat don't seal. They have to be worn to the cylinders[...]

Well, people smarter than me and with actual experience are saying that smoother finishes (or even unhoned broken-in finishes) are fine for sealing up the rings. It seems the crosshatch is what's important, and the extra roughness of a stone hone job is not necessary. http://www.babcox.com/editorial/ar/eb40250.htm
Some of their statements do sound a bit fishy, like why would the lack of plateau honing cause the engine to use more oil?? But overall it's not a bad article and there's more on the subject.

Whether you wanna follow this theory on a new engine or not is everyone's own call, I was just trying to say that it's probably not necessary to re-hone such a fresh engine, and just opens the door to more error. This is if he decided to open the bottom end, which he shoundn't in this case anyway.

Your theory definitely has merit to it, I just wanted to point out that other people say otherwise from experience. Here's another link on the subject: http://www.dsmtuners.com/forums/showthread.php?t=219422
Everyone can make up their own mind, I'm not trying to change your mind

 

[Enraged78]

One more thing I would like to add.

I would like to thank everyone who has contributed to this thread over the last few weeks. None of the issues I've had are easy to answer in any way, and the information you have all posted here has helped me immensely.

Thank you all for keeping your posts informative and civil. It makes this board a much better place for finding the information that keeps our cars running.

Thanks,
Matt.

 

[tsunari]

I'm curious . . . how is the head shop going to know if the valve seals are bad through mere inspection? Or are they most likely going to tear the head down and look at the guides for damage?

 

[Enraged78]

I'm curious . . . how is the head shop going to know if the valve seals are bad through mere inspection? Or are they most likely going to tear the head down and look at the guides for damage?

I'm not entirely sure. All I know is that the head shop I bought the head to for diagnosis was very familiar with my head. They correctly diagnosed my last head when everyone else was giving me "maybe" and "that's unlikely".

I do know that the head shop does plan on tearing the entire head down and checking valves, seats, guides, and seals. How they do this, I'm not sure, but this is what I asked for.

I know that the head shop is in the middle of the head right now. If it's a cheap fix, I'll let the head shop do it. If it involves anything else, it's going back to the shop that sold it to me. I already let them know what I was doing, and they had no problem with it. It sucks that I've had to go through all this grief, but at least everyone I'm dealing with is standing by their work. I'm not going to name either shop doing the work, just in case someone searches this thread in the future. Both shops are amazing to deal with, and I don't want a bad part soiling either of their reputations.

I also realize that by doing this, I'm incurring a diagnostic cost that I would not have had to bear if I just brought it back to the shop that sold me the head. However, I don't like the runaround, and I thought a repuatble second opinion was worth the extra cost.

Thanks,
Matt.

 

[tsunari]

I'm not entirely sure. All I know is that the head shop I bought the head to for diagnosis was very familiar with my head. They correctly diagnosed my last head when everyone else was giving me "maybe" and "that's unlikely".

I do know that the head shop does plan on tearing the entire head down and checking valves, seats, guides, and seals. How they do this, I'm not sure, but this is what I asked for.

I know that the head shop is in the middle of the head right now. If it's a cheap fix, I'll let the head shop do it. If it involves anything else, it's going back to the shop that sold it to me. I already let them know what I was doing, and they had no problem with it. It sucks that I've had to go through all this grief, but at least everyone I'm dealing with is standing by their work. I'm not going to name either shop doing the work, just in case someone searches this thread in the future. Both shops are amazing to deal with, and I don't want a bad part soiling either of their reputations.

I also realize that by doing this, I'm incurring a diagnostic cost that I would not have had to bear if I just brought it back to the shop that sold me the head. However, I don't like the runaround, and I thought a repuatble second opinion was worth the extra cost.

Thanks,
Matt.

I would have to completely agree . . . and am anxiously awaiting the results as I too am going to have to contact those who built my motor and let them know what's up. They already know about it burning so much oil, but really have no idea why. They only offered up that maybe I should switch to another brand of synthetic oil since there are a good number of cars that burn Mobil1.

Now that I think about it, I just did an oil change yesterday and didn't try another brand of oil . . . oh well, guess I wasn't thinking . . .

 

[tsunari]

So how about it man? Any word?

 

[Enraged78]

So how about it man? Any word?

Not yet. My machinist ran into some personal problems and I had to wait a few weeks. He pulled it apart last night, and should be giving me an answer later today. I'll post when he gets back to me.

Thanks,
Matt.

 

[tsunari]

Not yet. My machinist ran into some personal problems and I had to wait a few weeks. He pulled it apart last night, and should be giving me an answer later today. I'll post when he gets back to me.

Thanks,
Matt.

sweet . . . found out over the weekend that I am blowing white/blue smoke:

-Accelerating from a stop (engine is in vaccuum of course)
-Accelerating after a decel (engine is again in vaccuum)

So when the motor is in vaccuum . . . where would I be sucking oil into the combustion chamber from? Past the rings? Or perhaps the valve guides?

Doesn't smoke on initial startup from sitting overnite . . .

 

[Enraged78]

sweet . . . found out over the weekend that I am blowing white/blue smoke:

-Accelerating from a stop (engine is in vaccuum of course)
-Accelerating after a decel (engine is again in vaccuum)

So when the motor is in vaccuum . . . where would I be sucking oil into the combustion chamber from? Past the rings? Or perhaps the valve guides?

Doesn't smoke on initial startup from sitting overnite . . .

This is pretty much what I was getting. Granted, I wasn't getting too much of it, but it was enough to deprive the engine of a quart of oil in only 500 miles. I noticed mine more when I would get on the car hard and then let off. It wouldn't smoke under boost, but once you got back under vacuum, you could see and smell a little bit of it. It wasn't too bad under cruise, and it never smoked on initial startup from sitting overnight.

Either way, I do have the results from my machinist on my head, which hopefully will help you. As it turns out, the machinist who built my head did NOT put new valve guides in (which is funny, considering I paid for it...), and the valves were just barely on the acceptable edge. The valves are certinaly not good enough for a head that would run for 50,000 miles or better.

The guides were also egg-shaped, and there was over .003 clearance between the valves and the guides, which isn't horrible, but enough for it to burn oil. The valves were loose enough where you could move them within the guide back and fourth, much like a turbo with too much shaft play.

Either way, I was pretty pissed when I got the news. I brought the head and the numbers that my machinist got back to the original shop that sold the head to me. It looks like they will take care of it, but we'll see what really happens. I was halfway tempted to put better springs in there while it's apart again, but I really just want to get the car back on the road at this point.

Thanks,
Matt

 

[tsunari]

This is pretty much what I was getting. Granted, I wasn't getting too much of it, but it was enough to deprive the engine of a quart of oil in only 500 miles. I noticed mine more when I would get on the car hard and then let off. It wouldn't smoke under boost, but once you got back under vacuum, you could see and smell a little bit of it. It wasn't too bad under cruise, and it never smoked on initial startup from sitting overnight.

Either way, I do have the results from my machinist on my head, which hopefully will help you. As it turns out, the machinist who built my head did NOT put new valve guides in (which is funny, considering I paid for it...), and the valves were just barely on the acceptable edge. The valves are certinaly not good enough for a head that would run for 50,000 miles or better.

The guides were also egg-shaped, and there was over .003 clearance between the valves and the guides, which isn't horrible, but enough for it to burn oil. The valves were loose enough where you could move them within the guide back and fourth, much like a turbo with too much shaft play.

Either way, I was pretty pissed when I got the news. I brought the head and the numbers that my machinist got back to the original shop that sold the head to me. It looks like they will take care of it, but we'll see what really happens. I was halfway tempted to put better springs in there while it's apart again, but I really just want to get the car back on the road at this point.

Thanks,
Matt

Yup- sounds like you and i have pretty much the exact same symptoms . . . ~500 miles and I'm dumpin in 3/4 to a full quart of M1 10w30 Full Synthetic

As for your findings on the valve guides- that is quite interesting. Because the place that had my motor last . . . while it was in there I went ahead and had them put some SS valves in, new springs & retainers, and some new bronze valve guide inserts (as opposed to entire new guides).

Although it sucks, your findings definitely have me sufficiently excited to see that the culprit may have been found. I'm wondering if I should send my head to a local shop for them to check out or just send it back to the guys that did the work.

I've mentioned my situation a few times to the owner and he was completely stumped, but said that whatever I ended up doing that they would help me out. So anyone know of a good 4G63 Head shop in the Baltimore/DC area . . . perhaps even NOVA?


On a side-note . . . if you have the $$$, I'd say throw some springs and retainers in it while it's torn apart . . . will save a slight headache later on. But if you have to wait like 3 weeks for the parts to get in . . .well that's a judgement call on your part.