burning oil - Toyota Nation Forum : Toyota Car and Truck Forums

Eds1645 · 05-09-2007, 04:11 PM

yo. i got a 91 mr2 n/a. i burn bout 1 qt. every 1000 miles. i have 133000 miles. my teacher told me 1 qt every 10000 miles is in spec is that true? any suggestions. and hope to see all of you at the july 1st meet.

MRtuned · 05-09-2007, 05:00 PM

valve guides? have someone follow you driving down a long hill, and see if a little smoke comes out.

***toyomoho*** · 05-09-2007, 06:32 PM

Do you have white smoke at cold engine startup? The oil burning figure has been around for a long time (days of the big V8's). Personally, I think it is a bit excessive for a smaller 4 cylinder engine.

tHa kNiGHt FaLL · 05-09-2007, 06:46 PM

your teacher sounds about right. most combustion engines produce around 30 and some up to 40% blow by.

Older cars of course.

your issue is most likely piston rings or valve stem seals. if you don't notice a lack of performance i'd go w/ the stem seal. most older cars use a simple o ring. now they got the new posi-lock design that tends to perform better and last longer.

MRtuned · 05-10-2007, 02:09 AM

newer valve guide seals are the umbrela and positive. the positive seal fits on top of the valve guide, but the umbrella seal moves with the valve. general motors still uses the o-ring seals on their pushrod engines. I'm betting is either that, or, as tHa kNiGHt FaLL said, piston rings.

***MR2Jedi*** · 05-10-2007, 12:25 PM

1 qt per 1000 miles IS excessive. By the time you're ready for an oil change, you would have used up 3 qts! over 1/2 the capacity!I would have to agree with KnighFall . My 1 st suspect would be the valve seals. they are notorious for that. But will usuallly stop smoking after the engine is warmed up. Do a compression check. If within spec, most likely culprit would be the seals.

MRtuned · 05-10-2007, 03:50 PM

piston rings have to work harder than most people think. I don't know much about the 3s-gte piston rings specifically, so I dont' know if they are commonly a weak point. if it is the rings, you should replace them. if a 4 cylindar engine leaked 1/10th of a drop of oil every power stroke, then driving 60 mph for 600 miles you would use 45 quarts of oil! an engine should burn no more than 1/1000 - 2/1000 of a drop of oil per power stroke.

psypete · 05-11-2007, 02:03 AM

Quote:

Originally Posted by blackdelsol

piston rings have to work harder than most people think. I don't know much about the 3s-gte piston rings specifically, so I dont' know if they are commonly a weak point. if it is the rings, you should replace them. if a 4 cylindar engine leaked 1/10th of a drop of oil every power stroke, then driving 60 mph for 600 miles you would use 45 quarts of oil! an engine should burn no more than 1/1000 - 2/1000 of a drop of oil per power stroke.

he has an n/a, which is the 5sfe not the 3sgte.

more than likely it's the seals; i and other 5s ppl have the white/blue smoke and oil sucking. going to change oil this weekend to see if that's the case (i think i'm on 10k miles since the last change) and if it doesn't ill probably do my seals and whatever else might be burning oil.

Eds1645 · 05-11-2007, 10:42 AM

ya im low on cash so i think ill just wait and save up for a 3sgte swap. i could live with burning oil for a couple of months. and yes bluish white smoke on startups.

psypete · 05-11-2007, 01:07 PM

good luck with the swap. be careful who you get your rear clip from, ebay is not really reliable but some good vendors have stores on ebay.

btw if you can save up longer, go for the 3rd gen or higher if you plan on upping the power, but 2nd gen if you plan on keeping it mostly stock

w203 · 05-11-2007, 10:42 PM

How much exactly are oil usually burned for the turbo'ed MR2?

I know that the RX-7 (FD) burns 1 quart per every 1700 since I have to keep filling it up but thats rotary vs piston.

Tom 2000 · 05-11-2007, 11:26 PM

Quote:

Originally Posted by Eds1645

ya im low on cash so i think ill just wait and save up for a 3sgte swap. i could live with burning oil for a couple of months. and yes bluish white smoke on startups.

Common problem on 3S-FE and 5S-FE engines. The valve guide went bad on my previous Camry also.

I used a product called NO SMOKE from Bardahl from a local auto parts store.

It was cheap and it did help.

***MR2Jedi*** · 05-12-2007, 12:05 AM

Quote:

Originally Posted by Tangerine

How much exactly are oil usually burned for the turbo'ed MR2?

.

I'm usually alittle over 1/2qt. low by the time I do my reg. oil change.and I'm using dino..

Eds1645 · 05-12-2007, 10:16 PM

i was gonna get the rear clip from chicoraceworks

alltracman78 · 05-12-2007, 11:06 PM

1 quart every 1k is too much.
WAY too much.
1 quart every 3k is too much.

Do you do alot of high RPM driving?
This will burn more oil. Especially on an older engine.
The main and rod bearings throw more oil on the cylinder wall and the oil rings can't clean it all off, so some gets burned. You won't see the smoke from this though.

Run it to high RPMs and let it coast down while in gear.
If you see smoke your valve guides [not seals, guides] are most likely worn.

But my bet is also the seals. The 5S tends to wear these out at higher miles. Especially if you sludge up the engine [which can be caused by too long oil change intervals].

Quote:

Originally Posted by tHa kNiGHt FaLL

your teacher sounds about right. most combustion engines produce around 30 and some up to 40% blow by.

Older cars of course.

your issue is most likely piston rings or valve stem seals. if you don't notice a lack of performance i'd go w/ the stem seal. most older cars use a simple o ring. now they got the new posi-lock design that tends to perform better and last longer.

Blowby and oil consumption are two different things.
They don't really effect each other.

Excesive blowby is caused by weak/worn compression rings [or cylinder walls].
Oil consumption by the piston is caused by worn or clogged oil control rings.
Assuming the piston itself isn't damaged.

30% leakdown is VERY excessive. Most engines still running today should have well above that [to be considered healthy]. 10% or less is a "good" engine.

Quote:

Originally Posted by psypete

more than likely it's the seals; i and other 5s ppl have the white/blue smoke and oil sucking. going to change oil this weekend to see if that's the case (i think i'm on 10k miles since the last change) and if it doesn't ill probably do my seals and whatever else might be burning oil.

Good Lord.
If you run 10k between oil changes [even with syth] you are going to have problems.
That's double Toyotas recommened interval. And more than triple the 3K one.....