Get ready for a story book.
Alright so where to start... had the engine rebuilt local here in Houston and I've got maybe 10 miles or so on the motor. The motor smokes out the exhaust pretty heavily once the engine is warmed up (blueish tint, its oil). Under normal throttle and acceleration/full boost (7-10psi) it does not smoke. Come up to a stop light or pull into the driveway it eventually start smoking again within 30 seconds or less. To eliminate a few things from this conversation it is a twin turbo car and its not the turbos (no oil in intake piping, intake manifold, downpipes are dry and I have also ran the motor without the turbos to eliminate this and it still smokes at idle). It is not the PCV system as the car has two AN lines running to a vented catch can, no vacuum being pulled pre/post throttle body. A while back I took the intake manifold off and oil (approximately a teaspoon give or take) was on top of every intake valve except the cylinder on it's intake stroke obviously as it was opened. So I pulled the valve cover to inspect the valve stem seals on the passenger side since its obviously easiest and they seemed fine to me. Also head gasket was not blocking oil return ports down to pan as I thought maybe oil was building up inside the head area from this. I thought maybe it could be the rings but no way oil could end up on top of the intake valves other than bad valve stem seals or bad guides. In addition to that when I removed the turbos to remove them from the equation I saw oil accumulation at several ports of the exhaust flanges where they meet the head. I peaked inside the manifold itself and there is oil coming down from the exhaust ports. Just to eliminate the rings from the picture I did a cylinder leak down test at 100 PSI and there was 1% or less at every cylinder. I did a dry compression test also but I can't remember the numbers as its been some time I think they were like 160ish or so, motor is 9:1 CR. So I put it back together to just drive it some more making pulls to try seat the rings which I don't think it is personally especially after seeing the leak down test and it also feels strong with only 7 psi of boost. It's also on a Holley dominator, AFR is good, logs look great, it's not rich at idle or anything like that.
So fast forward to now as I have just lost motivation to work on the car as its been such a project for me and this is the second motor, first motor guy didn't know what he was doing. I don't drive it much as it's embarrassing with how much it smokes at idle to be honest. Good thing is I have just moved into a new house and now have a two post lift. I dropped the motor out the bottom two days ago. There is NO oil on the intake valves now although is still smokes as I had just driven it a few days before. I pulled both valve covers, nothing abnormal upon initial visual inspection. Next is to pull the timing cover and remove the cams so I can gets the springs off a few valves and feel for any play and the guide to valve stem. Also inspected the seals to see if there is anything going on. I bought new seals from Jordan at Modular Head Shop and at a minimum are going to swap those in if I don't find anything else. In my opinion its either the valve seals or the clearance is too loose at the guide and stem of the valve, which I really hope it is not as this motor is brand new. What was shocking to me was every valve had oil on it the first time I took the intake manifold off so I knew that the same issue was across the board, not just one cylinder, but now there is none it's clean as can be.
So at the end of the day I'm just here to see if anyone has been in this same situation before or shed any new light. Do I need to just drive it more? I've seen new motor before and they don't smoke like this at idle, it doesn't have stainless rings so I figured after some spirited driving and multiple pulls the rings would be set. Although since it only does it under vacuum (idling) it leads me to believe it is a head issue. I can search the internet for similar situations which there are plenty of them but no one has it with a brand new motor. I will update with any new findings in case anyone else ever has this issue. Anything I left out or any question feel free to ask!
Alright so where to start... had the engine rebuilt local here in Houston and I've got maybe 10 miles or so on the motor. The motor smokes out the exhaust pretty heavily once the engine is warmed up (blueish tint, its oil). Under normal throttle and acceleration/full boost (7-10psi) it does not smoke. Come up to a stop light or pull into the driveway it eventually start smoking again within 30 seconds or less. To eliminate a few things from this conversation it is a twin turbo car and its not the turbos (no oil in intake piping, intake manifold, downpipes are dry and I have also ran the motor without the turbos to eliminate this and it still smokes at idle). It is not the PCV system as the car has two AN lines running to a vented catch can, no vacuum being pulled pre/post throttle body. A while back I took the intake manifold off and oil (approximately a teaspoon give or take) was on top of every intake valve except the cylinder on it's intake stroke obviously as it was opened. So I pulled the valve cover to inspect the valve stem seals on the passenger side since its obviously easiest and they seemed fine to me. Also head gasket was not blocking oil return ports down to pan as I thought maybe oil was building up inside the head area from this. I thought maybe it could be the rings but no way oil could end up on top of the intake valves other than bad valve stem seals or bad guides. In addition to that when I removed the turbos to remove them from the equation I saw oil accumulation at several ports of the exhaust flanges where they meet the head. I peaked inside the manifold itself and there is oil coming down from the exhaust ports. Just to eliminate the rings from the picture I did a cylinder leak down test at 100 PSI and there was 1% or less at every cylinder. I did a dry compression test also but I can't remember the numbers as its been some time I think they were like 160ish or so, motor is 9:1 CR. So I put it back together to just drive it some more making pulls to try seat the rings which I don't think it is personally especially after seeing the leak down test and it also feels strong with only 7 psi of boost. It's also on a Holley dominator, AFR is good, logs look great, it's not rich at idle or anything like that.
So fast forward to now as I have just lost motivation to work on the car as its been such a project for me and this is the second motor, first motor guy didn't know what he was doing. I don't drive it much as it's embarrassing with how much it smokes at idle to be honest. Good thing is I have just moved into a new house and now have a two post lift. I dropped the motor out the bottom two days ago. There is NO oil on the intake valves now although is still smokes as I had just driven it a few days before. I pulled both valve covers, nothing abnormal upon initial visual inspection. Next is to pull the timing cover and remove the cams so I can gets the springs off a few valves and feel for any play and the guide to valve stem. Also inspected the seals to see if there is anything going on. I bought new seals from Jordan at Modular Head Shop and at a minimum are going to swap those in if I don't find anything else. In my opinion its either the valve seals or the clearance is too loose at the guide and stem of the valve, which I really hope it is not as this motor is brand new. What was shocking to me was every valve had oil on it the first time I took the intake manifold off so I knew that the same issue was across the board, not just one cylinder, but now there is none it's clean as can be.
So at the end of the day I'm just here to see if anyone has been in this same situation before or shed any new light. Do I need to just drive it more? I've seen new motor before and they don't smoke like this at idle, it doesn't have stainless rings so I figured after some spirited driving and multiple pulls the rings would be set. Although since it only does it under vacuum (idling) it leads me to believe it is a head issue. I can search the internet for similar situations which there are plenty of them but no one has it with a brand new motor. I will update with any new findings in case anyone else ever has this issue. Anything I left out or any question feel free to ask!
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