Derek The Great

Hey fellas, it's me. You guys know I can't just get to the direct point I've got to tell you a story first.

My car has been burning oil for years and I can't usually drive more than a tank of gas (~250 miles) without having to add a quart of oil. Being that it's a 305 i figured the valve guides and stem seals were bad again (dad had them replaced back when the car had ~50k miles) and so it got to the point I just let the car sit until i could save for new cylinder heads. Well, sit it did until I finally bought a set of aluminum trick flow cylinder heads and a full MSD ignition with a 6AL box to go along with it. I don't have the tools for heavy stuff like that so I had my local shop do the swap for me last year. I stick to simple stuff like brakes and tune ups.

Well after the swap I thought my nasty 305's oil burning days were over because it no longer burned oil on start ups (used to burn real bad if it sat for 2-4 hours and then was started back up again), it didn't burn oil if I revved it past 2k like it used to as well and it didn't burn oil on take offs like it used to. So imagine my surprise when I took a corner one day only to see my oil pressure drop off- I checked the oil immediately and of course the dipstick had only a sliver of oil on it. Fast forward to now and well occasionally I will see it make a puff on a full throttle take off but that's it. It's nowhere as bad as it used to be, before it would make a smokescreen, which is why I stopped driving it. Also, after it's been running if I take the oil cap off smoke of some sort wafts out of the oil filler hole. Kind of looks like steam. I don't know if that's good or bad. The engine seems to be in good shape which is why I swapped the cylinder heads instead of the entire motor. I get into it often and when I look in the mirror when it's revving past 4k I don't see any smoke so I don't think the oil rings are bad. It doesn't leak any fluid whatsoever, and since the cylinder head swap I've started using full synthetic Castrol Syntec 10w-40. Before that it was always conventional Castrol 10w-40. I change the oil ever spring and during the months I drive it (April - October) I put maybe 2500 miles on it. Dad gave it to me in '04 with 100k on it and it just rolled over 115k today.

So why does my engine still burn oil? Does anybody have any ideas? If you need more info I'll be happy to provide it but I'll list as much as I can remember and I'm sure some of it doesn't even matter.

Thanks in advance for your answers.

-Trick Flow pre-assembled aluminum cylinder heads (I forgot which ones but they were new and I have the paperwork somewhere)
-Edelbrock Performer TBI intake manifold.
-180* Thermostat
-MSD Ignition system
-Champion spark plugs
-AC Delco Oil filter pf 1218

redneckjoe

i hate to say it but it sounds like blow-by. do a compression test. perhaps some open-element breathers would be better then useing the PCV? ive also seen rear main seals leak and throw oil on the exhaust pipes at high RPMs, ....lots of smoke. let us know what you find out.

Derek The Great

Thanks Joe,
So my rings are shot then? I can't think of anything else that could cause the car to burn through so much oil. I mean at the rate it gulps it down wouldn't I see it coming out the tail pipes at all times?
I don't think I've ever replaced the PCV valve so I'll throw a new one one for S&G's. The car doesn't leak any oil now, before I had the heads put on it did and so I thought it was the rear main because it would drip right between the oil pan and trans. Anyhow I don't have a compression tester and the car is going to be stashed for the winter soon. I've been dealing with it like this for years and I'm sure my dad did too althought he wasn't as religious at checking the oil like I am so who knows, he could've run it dry a few times. How bad is it to run the engine with the oil level below the operating range?

Damon

What you're describing sounds like more oil than old rings could account for, especially given the lack of a "smoke screen" behind you. THey're probably tired and leaky, but not one quart per tank leaky.

So does it still drip out the rear main? Do you have oil coating everything rearward from there, like the trans pan? Rear mains can leak more when you're out on the road at elevated RPMs (and accelerating) than they often will just idling in the driveway.

How do the plugs look? Do they foul out quickly, like bad rings would tend to do?

Do you still use stock-style baffled valve covers? Running a PCV without a baffled covers can cause the PCV valve to drink a lot of oil flying around off the rocker arms.

mmadden55

It is likely losing it through the rear main seal, but do a compression test. Once you have an average for all cylinders, they should all be close. Put a teaspoon of motor oil in one cylinder and test that one again. If the pressure comes up significantly it is the rings.

cprmn14

iTrader: (3)

If it was out of the rear main seal he would have a good size puddle under the car with how much oil hes loosing. Sounds like really bad rings to me, I had a Dodge Stealth in high school and it did the same thing. Is it worse if you let it idle for a few min?

Derek The Great

No leaks whatsoever.. I had the trans filter replaced a couple months ago and I was under the car this past weekend to look at the new rear end and grease up the ball joints and stuff. The pan was squeaky clean from when they washed in in their parts washer. The only oil that remains is the old stuff from when it was leaking from the intake manifold, valve covers or both.

Before the trick flow heads got put on it would almost always burn oil on take off or when I nailed it getting on the expressway, it would produce a really heavy cloud of smoke too. Now it occasionally makes a small cloud but nowhere near as dense or often. It also used to burn oil if you took it past 2k in park or neutral or once started after it sat for less than 4 hours.

The valve covers are stock. When I switched to a 14" open edelbrock air filter I bought a K&N breather for the passenger side cover and left the stock PCV untouched.

Sometimes it only goes through half a quart of oil during a tank of gas. But last week I drove it up through canada and back and when I put gas in it it was a quart and half low. Yikes. Does running an engine below opperating range hurt it?

Derek The Great

Also, the plugs are good. All of the ignition components were replaced back when I did the cylinder head swap. Eventually I plan to put a 350 in it so I made sure all of my mods would swap over. Anyhow, the car runs great. It just rolled over 115k and still pulls pretty hard, it doesn't seem tired but I'm just at a loss when it comes to how much oil it uses.

Lastly, I hate to say this and hope you guys don't bash me but I doubt I'll be checking the compression. I've never done that before and I don't have the tools to get a few of the plugs out, nor do I have the compression checker. I might do it next year though, I've just spend enough money on the car this year and my free cash is just about all spent. Infact, in the past two year I've spent more than 3500 on it. Over the winter I wanted to get a set of ceramic coated hooker 2055 headers and have Keith's Muffler shop in Westland bend me a nice 3" stainless exhaust and then lastly, put a new headliner in it. Needless to say, dad wants the car back haha.

grumpyvette

it sure sounds like either worn or improperly installed rings, keep in mind if compression rings are installed upside down they pump oil. pistons can get damaged bye heat detonation, or lack of oil,and prevent rings from sealing, and if you had a bad intake gasket it can suck oil from the lifter gallery, and if the valve retainer hits the valve seal because the valve clearances are not correct it will quickly destroy valve seals
Id start with a cylinder leak down test and pulling the valve covers and closely visually inspect the valve seals
http://forum.grumpysperformance.com/...php?f=53&t=247

http://forum.grumpysperformance.com/...hp?f=53&t=3897

http://forum.grumpysperformance.com/...hp?f=53&t=5454

http://forum.grumpysperformance.com/...e+seals#p26186

http://forum.grumpysperformance.com/...e+seals#p19781

http://forum.grumpysperformance.com/...e+seals#p17973

http://forum.grumpysperformance.com/...eakdown#p14272

Derek The Great

Thanks the the links Grumpy.
I bet the rings are trashed. The bottom half of the motor has never been apart so I'm sure the rings are properly installed. How the hell could they be worn out after only 90k miles? What happens when you run an engine with it's oil level below the operating range?

ex-x-fire

Adding fresh heads to worn short block usually causes an oil consumption problem (or makes a bad problem worse).

Damon

If you've got pressure on the gague, you're OK. That usually means it can be off the bottom of the stick and still suffer no damage. But when you go around a turn and see the gague wiggle- you've let it get too far down.

There's only two things that can explain a falling oil level- it's burning it or it's leaking it. Since you say it's not leaking anywhere that only leaves one possibility. The new heads obviously made a significant difference (fresh guides and guide seals count for a lot) but they won't fix a problem with the rings, obviously.

Unless there is new information we don't know about yet, you're looking at a ring problem. Just worn out or......

Has the engine ever been overheated??? You can overheat a motor and kill the TENSION of the rings, causing a problem with poor seal. There won't be any obvious physical damage but when/if you take the motor apart the pistons will pop out of their bores very easily because the rings aren't tight against the bore. Like a spring that's been overheated it just looses it's tension.

Derek The Great

Well the oil consumption didn't really change with the new heads, if anything it's slightly better now then it was.

Well it's good to know that the oil level can dip below the operating range, my one buddy told me that the crankshaft dips into the oil and slings oil up into the pistons but wouldn't that happen from the oil coming off of the main bearings?

My dad owned the car since 95. It only had 36k miles on it then and now has a grand total of 115k. He gave it to me with a little over 100k. As far as I know the engine has never overheated. The motor is strong though and with the mods its fairly quick. God I remember when I first got it wouldn't do a brake torque with the A/C on.. Now doughnts are not a problem and the A/C doesn't affect it.

IrockMyCamaro

Hello everyone! Im pretty new to all this car stuff because im only 17 but i have a 1989 Camaro rs. its a vert V8. I couldnt get the car to pass the smog so i took it to a mechanic and they told me that it burns oil. what are some quick things i can do to fix that? please break it down into simple terms. or if you know where i should take it to get it checked by someone more experianced with these cars. i live in garden grove so a close place would be preffered. thanks alot for anyone who has any tips!