Smoking issue continued.

[spyderdrifter]

So after stressing over my smoking issue, I finally got a leak down test done last night. All cylinders were pressurized to 95psi @ TDC on compression stroke. No leaks in any cylinder what so ever. I followed this with yet another compression test which resulted in 125psi, also on every cylinder. For those of you who haven't followed progress with my Spyder, I replaced the piston rings and all corresponding bearings, bolts, seals, and gaskets related to pulling the engine apart for the ring job only 2000 miles ago. I did a proper "balls to the wall" break-in to seal the rings. My car still smokes and it usually looks white, but there's potential for it to be a very faint blue as there's a burnt oil smell to it and I'm not leaking coolant at all. I'm not leaking oil anywhere either. My turbo seals being bad has been suggested by a couple people, however, I'm inclined not to believe my turbo is the culprit for whatever is going on. It got rebuilt this year by Justin and has been nothing but awesome since putting it back in the car.

So I guess if there's a question here to be asked, it would be what could possibly be causing my smoking? The valve seals were replaced over this summer, the guides were replaced last summer along with a valve job. I've installed a filter on the vent line from the valve cover to the intake pipe, and I've checked the PCV system, which the valve too is fairly new. It's not OEM and came from Advance Auto (unfortunately), but it works properly. I'm at the end of ideas so I need some fresh ones.

 

[dsmcurse]

I have had a HOLSET HX52 smoke after having fresh piston ring installed, just cause shes rebuilt dont mean she cant smoke still. For what its forth, swap the turbo out with another just to rule that out.

 

[biglady112]

If the turbine housing, exhaust wheel or collar under the exhaust wheel are wet and covered in oil, it is your turbo. If not, it is your engine. Usually when you pull the exhaust manifold you will see which cylinder is wet and that is where your problem lies.

 

[spyderdrifter]

I have had a HOLSET HX52 smoke after having fresh piston ring installed, just cause shes rebuilt dont mean she cant smoke still. For what its forth, swap the turbo out with another just to rule that out.

Yeah, I hadn't ruled out the possibility of the turbo smoking, but I just don't want that to be the issue since it got rebuilt by a very reputable rebuilder. I also don't have another running turbo to just swap out with, unfortunately.

If the turbine housing, exhaust wheel or collar under the exhaust wheel are wet and covered in oil, it is your turbo. If not, it is your engine. Usually when you pull the exhaust manifold you will see which cylinder is wet and that is where your problem lies.

I'll pull the turbo and manifold off this weekend to inspect it all. Thanks for the idea.

 

[WES_393]

125psi is very low for an engine with new rings. Are you sure there was no blow-by during the leak down test?

 

[spyderdrifter]

I'm positive there's no blow by. I redid the test last night and there's 5% leakage on all cylinders which is still good. I also did a boost leak test and everything is good. No idea why compression is so low when I get good performance from it.

Update:

Redid boost leak test to make sure BOV flange was sealed again and it is. After that was sealed, I did the boost leak test for each cylinder while that cylinder was at TDC for compression stroke. On cyl 4, and ONLY cyl 4, the cyl 1 injector leaked air at the grommet that holds it into the manifold port. I'm assuming it leaked because air returns to the manifold via the EGR port in cyl 4. Whatever the cause, I'm buying new grommets for all injectors since I'm quite sure they're the original 16 year old parts. Nothing else leaked during that test.

 

[JacksonAuto]

If leakdowns are good the low cranking compression could be the cam timing. Too much overlap and the compression is going right out the exhaust.

 

[spyderdrifter]

So what's the best way to ensure there's good cam timing? Timing light right?

 

[biglady112]

His compression is very normal for our altitude.

 

[spyderdrifter]

So, biglady (), 125-130psi is normal for a rebuild at 6300ft? Not doubting you, but just doesn't seem right when it should be in the 178psi range.

 

[biglady112]

My brand new engine in the truck is 130psi cold with the throttle closed.

 

[spyderdrifter]

Wow. Guess I shouldn't worry too much then. Good to know.

 

[biglady112]

Did you pull the exhaust housing or exhaust manifold to see where the oil is coming from yet?

 

[spyderdrifter]

No, not yet. I've been putting it off for some reason. But the gf isn't home tonight so I guess I can do it. I ordered new injector o-rings and valve seals the other day just in case.

 

[Tyeler18]

My brand new engine in the truck is 130psi cold with the throttle closed.

That is actually pretty low. My 185k stock long block galant made 135-140psi at 8000ft, and my fresh rebuild (stock compression) long block in my 1g made 150 across all 4 at the same altitude. I haven't checked it now that I'm about at sea level, but regardless I had much higher compression on both engines than either of yours, using 7.8:1 pistons.

 

[biglady112]

Well I have big boy cams. Made 800hp, I am sure my engine is quite healthy. I have been racing Mitsubishi's in Colorado for 15 years. We are both right in line with what every other DSM I have worked on has come back as. We had one engine with baby cams do 145. Again, mine was cold with the throttle closed.

We need to get back on topic. His compression is not his issue. Pull the exhaust apart and report your findings.

 

[Tyeler18]

Well I have big boy cams. Made 800hp, I am sure my engine is quite healthy. I have been racing Mitsubishi's in Colorado for 15 years. We are both right in line with what every other DSM I have worked on has come back as. We had one engine with baby cams do 145. Again, mine was cold with the throttle closed.

We need to get back on topic. His compression is not his issue. Pull the exhaust apart and report your findings.

Yea with cams that sounds about right, but he is on stock cam's, with 2g compression. It should definitely be higher even at altitude, so it is still a potential issue. 7 bolt service limit is 131, he's already below that on fresh rings. Granted I've run them down to 90psi before and not had smoke issues, but I've also had some at 130 that smoke from the rings. I've owned 30+ of these, quite a few when I was in Colorado as well.

 

[spyderdrifter]

6 bolt service limit is 121 or 123. I forget which, but that's what I got. But will pull the exhaust in a little while and let you all know what's going on from there. I honestly hope it smokes from there. Haven't seen much smoke all weekend though.