Engine burning oil

Does anyone know how i can use my scope and transducers to figure out why an engine is smoking badly after cam and lifters installation. Guy tells me they rebuilt engine and had a small cam put in it when short while after they developed a ticking noise. After lifter replacement the engine noise is gone but now smokes. Smells rich and I really smell burning oil.Would like to test so i can learn from this

You can put a pulse sensor on the dipstick tube, while doing a Relative Compression test.

I did do a pulse sensor on the dipstick but the engine was running and i synced to an ignition event. Really couldnt tell if anything looked out of place. Should I do it while cranking only and add RC to it?

chris.arriazola wrote: Should I do it while cranking only and add RC to it?

That's how I would do it. Cranking compression is higher than running compression. If you have an RC hump that is low, look for a Crankcase pulse that is, simultaneously, high. This would indicate bad piston rings. If all cylinders produce the same RC hump and Crankcase pulse, then this is not a good test. It only looks for "the odd-man-out". If RC and Crankcase pressure are uniform, then I recommend a Cylinder Bleed/Leak down test.

How is the PCV system? Do you have oil in the intake?

The smoke wasn't present before the cam change ?
Is the smoke worse when you raise the RPM after the engineis allowed to warm up then allowed to idle for a minute so ?
I am thinking either a PCV fault or a valve stem oil seal damage

Havnt checked the pcv yet. I wanted to scope before i find a problem to help diagnose in the future. I have to start checking everything tomorrow before i run out of time with it

Thats what i was thinking but want proof. I will continue to test tomorrow. Thank you

If it were me this is probably how I would do it. Pull plugs and find out what cylinder or cylinders are burning the oil. This will get you in the correct area. To me I like to atleast narrow down my search as much as possible. You didn't say what vehicle this is on. If you have a microphone setup to you scope you can pull the valve covers, put the cylinder at TDC and pressure up the intake some. put the microphone above the valve guide on the cylinder that is burning oil and one that is not that is also at TDC and check the difference. Can also do this with the exhaust if you can drop it and build a block off plate at the collector with a air fitting on it a do the same at the top of the exhaust valve guide and check the difference. I would imagine you could do the same with a microphone by the oil pan or drain the oil and and stick the microphone in the drain oil and do a leak down test and pressure the cylinder up. I'm not sure this would tell you much of anything though if your compression rings are good and just an oil ring collapsed. If you can narrow it down to the cylinder and either confirm that the valve guides are or are not the problem that will put you further ahead. I have not actually done this, just thinking in theory. I know we use ultrasound detection in the industrial setting to find airleaks. If oil is getting through, it should be fairly easy to detect a difference in air leaking. Just depends how far you want to dig in and how much time you want to spend on it. Either way, good luck to ya and will be interested to know what you come up with and how you went about troubleshooting it.

You also could hook up a pressure transducer to the PCV system while it is running to make sure you don't have excessive back pressure. I'm guessing that is the same kinda thing Chad was suggesting by his advice. If you "T" into the PCV system while it is running you could further get a grasp on the pressure. I know certain vehicles like my powerstroke have specs for the actual crankcase so I really couldn't tell you want that one should be running at or even if there is one.

I forgot to mention im working on a 93 f150 with5.0. I tried RC,ignition and dipstick tube pressure while cranking but nothing caught my eye. I was hoping to see something stand out.Was hoping to learn from this engine but the guy is getting impatient. I broke down and uncovered valve cover to loosen valves and do leak down test which showed excessive leak in crankcase. on the first cylinder i tried.That was enough evidence for us to pull engine. Wished the guy would of given us more testing time .To make things even worse i didnt save captures to analyze at a later time.

chris.arriazola wrote: i didnt save captures to analyze at a later time.

I have made it a habit of saving waveforms before I even look at them. I save them in their own folder, according to work-order. As I learn more, it's fun to go back and look at waveforms, that I captured a long time ago, and see NEW things that I didn't see, before.

I hope that you've managed to fix your issue. Let us know how your car is doing. The most common cause of smoke under the hood is small amounts of motor oil or other fluids accidentally spilled or leaking from a bad gasket or seal onto a hot engine or the exhaust system. Those other fluids may include engine coolant, power steering, brake and transmission fluid, even window washer solvent. Smoke often leaves car engines as a result of overheating. According to cararac.com/engine_oil/ , this can be caused by faulty wire casings, heated residues on the engine block, and overheated liquids.