4g63 burning oil, what are my options and at what cost?

[jepherz]

The motor in my DD vr4 is making oil disappear at a tune of about 1 qt. every 4-500 miles. I have no idea how many miles are on the engine as I know it's not original to the car, the rear bumper has dark soot on it (stock exhaust with cat) and I often find the dipstick partially out of the tube, indicating blow by. There are no oil leaks that I see, the 14b has been recently rebuilt, and the head was gone through a few years ago and has about 15k miles on it. I know that the front balance shaft had seized before I got the car, and I'm using the same oil pump since removing both shafts so it's possible that the whole shebang ran through some metallic oil for a bit? I don't know. Gas mileage is on average 21 mpg, so is it possibly that MPGs are being affected by this too?

I'm looking to figure out what my options are and approximate costs of each. The car is completely stock and I intend on keeping it that way. Stuff like engine in/out of car rebuild, just replace bearings, oil pump and rings, full machine work, etc. I've never rebuilt an engine, so tips like the necessity to bring the block to the machine shop before knowing if I need to order new pistons and go 0.020 over etc. would be very helpful. Maybe I'll find that it's not worth a rebuild and I'll just keep throwing oil at it...

Thanks for any tips.

 

[IncorpoRatedX]

Do a compression test and get back to us, then we'll go from there...

 

[turbowop]

503 goes through a lot of oil, but compression numbers are okay and it doesn't smoke. Gets decent mileage as well. I just keep throwing oil at it. /ubbthreads/images/graemlins/grin.gif

 

[jepherz]

Quoting Alpha Male:
Do a compression test and get back to us, then we'll go from there...



Will do. I know I got them before when I put the new head on and they were within tolerances, but I will grab them again tomorrow. Thanks for the suggestion.

Quoting turbowop:
503 goes through a lot of oil, but compression numbers are okay and it doesn't smoke. Gets decent mileage as well. I just keep throwing oil at it. /ubbthreads/images/graemlins/grin.gif



Mark, how much oil are you having to 'throw' at it?

 

[IncorpoRatedX]

click

problem solved; you'll be able to drive farther between 'fill ups'

 

[turbowop]

Quoting jepherz:


Mark, how much oil are you having to 'throw' at it?



I don't really keep track of mileage/consumption, so I'm not sure. Since I drive my company van from home, none of my vehicles are true daily drivers. I think the synthetic oil in 503 is about 8k miles old, with a few fresh quarts thrown in throughout this interval. I should probably change it soon. /ubbthreads/images/graemlins/rofl.gif I just check it every couple weeks or after long trips and add a quart if it gets down to the lower dipstick mark. Just over the weekend I drove it to see my girlfriend, which is a little over 300 miles round trip. According to the dipstick reading before and after I burned just under a 1/2 quart.

 

[grocery_getter]

Do a dry and then do a wet compression test. Good to see just what the numbers are at. If you do do a dry and wet comparison, make sure you put the battery on a charger so battery voltage to the starter is same from starting to finish. Block the throttle open, take out the CAS connector, disable the clutch pedal switch (so you dont have to push on your clutch) and crank away.

 

[Wizardawd]

A dipstick out of the tube isn't a good indicator of anything other that the rubber around the stick is worn and doesn't hold well. All motors will always have blow by. But, like they said, do a compression check. That will tell you how the compression rings are. But, they won't tell you how the oil control rings are. You can have great compression rings but sticky OC and still burn oil. But, if the compression rings are worn, you might as well change both.

Does it smoke during startup? How about if you let it idle for a while? Any leaks?

Wiz

 

[jepherz]

Nope, no visible smoking at all, or leaks. Just the soot on the bumper.

 

[bazeng]

My motors drink oil also.

PITA.

I just top it up.

 

[Specter]

I see many people add oil after some miles without any obvious motor issues. Is it because of the stock vacuum pipe on the valve cover? One going to the manifold and one to the Intake? Does the oil go through those pipe in the cylinders and slightly burn in the cylinder with no obvious smoke? /ubbthreads/images/graemlins/dunno.gif