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Old 08-29-2011, 11:40 AM   #1
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Default best way to solve burning oil/shitty rings

i'd like some input on my situation here.
i burn about half a quart of oil every 200 miles or so. if i don't go wot, i can last a little bit longer.
i haven't tested compression yet, but i'm assuming the rings are bad.
my car is a 91 shell, 94 wiring harness with a 99 engine.
i'm going to go ahead and *assume* the head is fine.

i'm currently using 5w-30 but plan on switching to 10w-40 as a precaution.

if you had shitty rings, would you...
1) rebuild with oem stuff
2) rebuild with forged internals (i'm assuming this is going to get a lot of votes, but not within my budget)
3) find an engine (94-00) with good compression and use my head.
4) something else?

budget?
let's say 1000-1500
i don't have the means to swap anything myself, so i have to take into consideration labor and a shop to do the work.

your thoughts please...
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Old 08-29-2011, 11:43 AM   #2
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new block is easier...just a HG away.
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Old 08-29-2011, 11:45 AM   #3
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I spent $1300 on labor for my rebuild. Rods and pistons were sub $800. Yes, it's more money, but it will last a very long time if you get a good machinist. Talk to TSE about a package deal. Buy a hoist and you can swap the engine yourself, you'll learn something.
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Old 08-29-2011, 12:13 PM   #4
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On the cheap- yeah, an earlier 1.8 short block is simple and cheap- it's just a matter of finding one.
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Old 08-29-2011, 12:22 PM   #5
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BTW, oil consumption does not necessarily mean your rings are bad. There are lots of ways that head issues can result in oil consumption. Also, the amount you're using could come from a leak, especially a front or rear main seal. Turbos consume also. Perhaps a bit more diagnosis is in order before jumping to conclusions.

Of course, a quality rebuild would address all of these issues. But, you may not need to bite that bullett yet if funds are tight.

Last edited by hornetball; 08-29-2011 at 12:32 PM.
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Old 08-29-2011, 12:23 PM   #6
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Assuming it is a ring problem, I'd throw out option 1. Then base the decision between option 2 and 3 on power goal vs available funds. If you're looking for cheap just find a bottom end and swap it. If you're looking for power, build the block you have.

If you're paying for the labor, this would be a good time to consider if you're going to need a clutch soon. If the motor is coming out anyway adding a clutch install to the bill shouldn't affect labor costs.
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Old 08-29-2011, 12:43 PM   #7
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thank you guys!
i'm still naturally aspirated.
i don't think there's a leak. i never see oil marks on the undertray or underneath the car.
my understanding of seals is that there would be a visible and steady leak while the car is idling. i see nothing of the sort.
the engine was installed in this car about 3000 miles ago and all seals were replaced at that time.
the car already has an upgraded clutch as well (not anything to do with burning oil, just a sidenote for pdexta) by the previous owner - act street disc, act extreme pressure plate and 99 flywheel

my only issue with replacing the block is *knowing* whether or not everything is copacetic. i guess a compression and leakdown test could be in order, but not exactly easy to find a block in the ******* poconos.

planet miata isn't too far though.
any other ideas or suggestions would be great!

looks like i'll be trying to source an engine in the meantime

Quote:
Originally Posted by hustler View Post
I spent $1300 on labor for my rebuild. Rods and pistons were sub $800. Yes, it's more money, but it will last a very long time if you get a good machinist. Talk to TSE about a package deal. Buy a hoist and you can swap the engine yourself, you'll learn something.
and to touch upon this...
i agree, it'd be great to do the swap myself. and you're absolutely right, i'd learn a ton!
but i have no garage.
where i park is in mud, not even blacktop or concrete.
so space is limited to say the least.
maybe in a different life...lol
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Old 08-29-2011, 01:00 PM   #8
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My rear main was leaky and i never saw a drop on my driveway. Sometimes small leaks will just get stuck under the car and you will never see it untill you go to replace
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Old 08-29-2011, 01:03 PM   #9
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like i said, the seals were replaced when the 99 engine was put in the car. around 3000 miles ago.
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Old 08-29-2011, 01:19 PM   #10
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Does it smoke (or smoke worse) on start up when cold? I used a cylinder head that was sitting forever and the valve seals were shot. It would smoke worse when cold and under heavy vacuum. Also had an engine with a broken oil ring. Compression was perfect, but the car would smoke bad on startup. Once the compression rings warmed up and expanded they did a good enough job of oil management that the smoke would disappear BUT it was still burning oil.
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Old 08-29-2011, 01:24 PM   #11
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i seldom see a lot of smoke pouring out of the exhaust. but my bumper is black and it smells of burnt oil.
i had someone follow me when i went wot to smell it.
with that being said, a few weeks ago on a very hot day...
there were two times, once in second and once in third at about 3/4 throttle, big poof of black smoke came out of the exhaust.
i felt bad for the girl behind me in her convertible, but whatever.
hasn't happened since.
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Old 08-29-2011, 01:31 PM   #12
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1: Buy miracle product intended to be poured into radiator.

2: Pour product into oil filler.

3: (?)

4: Profit.
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Old 08-29-2011, 03:36 PM   #13
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Do a compression test and pinpoint the oil leak.
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Old 08-29-2011, 04:16 PM   #14
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Quote:
Originally Posted by phillyb View Post
with that being said, a few weeks ago on a very hot day... there were two times, once in second and once in third at about 3/4 throttle, big poof of black smoke came out of the exhaust. i felt bad for the girl behind me in her convertible, but whatever. hasn't happened since.
Just a data point, oil smoke is not black.

Since you're going to be using a shop to swap the block, surely you can ask that shop to do a leakdown test for you?
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Old 08-29-2011, 04:21 PM   #15
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yeah absolutely.
i'm not really anywhere near ready to start this.
this is more of an informational thread for me.
oil smoke is blue, eh?
i mean, i'm talking about a big poof of smoke coming out of the back of the car.
it wasn't white - so it wasn't coolant.
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Old 08-29-2011, 06:25 PM   #16
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Blue-White. If you've ever been to an airshow, you've seen oil smoke. They pump oil into the aircraft exhaust to make white smoke.

A big poof of black smoke/black bumper points to a rich mixture. Too much acceleration enrichment?
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Old 08-29-2011, 06:28 PM   #17
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eye dee kay
def smells like oil
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Old 08-29-2011, 06:36 PM   #18
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Quote:
Originally Posted by hornetball View Post
A big poof of black smoke/black bumper points to a rich mixture. Too much acceleration enrichment?
Excessive accel enrichments look like this:

Start at 8:25. Excessive enrichments at 8:33, 8:40, 8:46. Totally invisible from inside the car, and more of a grey than a white/blue.



OP, do a compression/leakdown test.
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Old 08-29-2011, 06:46 PM   #19
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I 12th a compression test. Also I would pick option 4. Rebuild with OE pistons (If possible) and cheap rods and maybe a BE opg. That would be cheap, effective, and work.
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Old 08-29-2011, 06:48 PM   #20
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yeah, compression test to eventually come.
oem pistons...?
interesting. i guess i'll have to read a lot more about what breaks first, but to replace with oem pistons and forged rods seems...idk...
but if the oem pistons are strong enough, why not
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