First tercel burning oil

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Dawson Muth
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Posts: 1
Joined: Thu Nov 24, 2022 12:21 pm
My tercel:: 1983

First tercel burning oil

Post by Dawson Muth »

HI everyone! I just got my first tercel. It's a beautiful 83 and I want to make it my daily. I live in an area that has emissions though. Before I say anything else the car was sitting for 2-3 years.

Anyways the car was exhibiting symptoms of bad valve stem seals. On startup, it would blow smoke out the tailpipe (presumably oil because it left an oily stain on the ground) I can't tell if it's blue or white but a little black smoke is mixed in there. I could rev it a few times to clear it out and then once the car warmed up I could drive it normally. It spits a tiny bit of smoke when you rev it warm but not much at all. It also idled like crap when cold.

I replaced the stem seals and they were definitely dried out. My problem got less severe but only slightly and it still spits oil out of the exhaust when cold. I checked my compression and I've got about 140psi on all the cylinders and my cylinder walls look good. I can still see the crosshatching with a borescope.

I hooked up shop air to the spark plug holes and found that there was air hissing out of the filler cap which I presumed meant bad rings. The previous owner said it didn't smoke for him so I assumed they were all stuck somehow even though I had been driving the crap out of it. I poured berrymans down the cylinders to let it soak and it all seeped past the rings. I started it up let it idle a bit and changed the oil. I'm still having the same issue and I'm left wondering if maybe the leakdown is a normal amount and I just damaged a valve seal (which seems unlikely because I was gentle) or maybe the rings are all just evenly worn down and I'm burning oil because of that.

It also smells awful and I can't tell if it's because it's running rich or if it's because of the oil burning. I desperately need some expert input here. I'd love to drive the car but I can't get my dang plates until I pass emissions. Should I pull the whole engine and rering it or is my problem possibly not that serious?
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dlb
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Joined: Mon Jul 06, 2009 9:03 pm
My tercel:: '87 sr5, '83 dlx parts car
Location: bc, canada

Re: First tercel burning oil

Post by dlb »

Welcome to the forum, DM.

Have you gone over the emissions systems yet? They seem like a lot at first glance but if you use the factory service manual (aka FSM) found on this site and go over each system on its own, it's pretty easy to make sure each system is working and they are connected properly. My guess about the bad smell is that some of the vacuum hoses are routed incorrectly and that's causing it to do the wrong thing at the wrong time.

140 PSI shouldn't be causing much burning oil but if you want to err on the side of caution, you can add Restore engine additive when you do oil changes. I've used it with success in the past, and there are some good videos of people testing it on youtube.
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Petros
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Joined: Sun Jan 28, 2007 6:31 pm
My tercel:: '84 Tercel4wd w/extensive mods
Location: Arlington WA USA

Re: First tercel burning oil

Post by Petros »

welcome,

if you damaged a new valve stem seal as the cause of your oil seepage, you would not get a hiss out the oil filler during the leak down test. likely the rings are worn, or still gummed and sludged up from sitting so long. it may take several seafoam or berryman's treatments to free it up. there are various ways to get the sludge out from around the rings: allowing it to soak after putting it down the spark plug hole is one, but you can also add it to the crankcase oil. I know of some that pour it down the carb while the engine is on fast idle, when it stalls out, they let it sit overnight. than start it the next day. or you can try a combination of similar treatments. sometimes it works wonders, others times, not so much. after that you can try adding a can of "Restore" to the crankcase (after a fresh oil change), and drive it at highway speeds for a long day (best do this when you are planning a road trip). the particles in the Restore tends to settle out of the engine oil if you let it sit after your allow it run for short period. it will seal up rings and valve stems remarkably well if they are worn out, and not gummed up and stuck.

If this works you should notice a bit better econmy and power, a high compression, and you can put off major engine work for a long time. you should be able to pass emissions testing I suspect too, though you should go through the FSM emissions chapter and test or check all the systems for proper operation before you have it tested. look for correct routing of all the vac lines, and that all are in place, and none are damaged or cracked.

good luck.
'87 Tercel 4wd SR5 (current engine swap project)
'84 Tercel 4wd (daily driver, with on going mods)
'92 Mazda MPV 4wd (wife's daily driver)
'85 Tercel 4wd DLX auto(daughter's daily driver)
'01 Honda Civic (other daughter's daily driver)
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Mark
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Joined: Mon Apr 22, 2013 9:49 pm
My tercel:: 1984 Automatic, 1981 sedan
Location: Victoria, B.C.

Re: First tercel burning oil

Post by Mark »

Mine smokes out the tailpipe on cold days for the first couple of minutes, It's not oil though, but a mix of water vapour (a normal byproduct of combustion) and unburned fuel vapour. The fuel vapour gives it a stink. Could this be what's happening with yours? I've been trying to figure out why I'm having incomplete combustion when it's cold out (my other Tercel doesn't do this). I've had bad stem seals before (every few years actually) and the symptom is when you're sitting at a red light and idling and then the light turns green and you accelerate, then there's a puff of smoke. This happens more often when the engine is warm and the oil is warmer and thinner. I've had the smoke on startup and while driving before in my '85 van. I assumed the oil control rings were stuck and gummed up in the pistons from sitting for several years. I did the Seafoam treatment and it still smoked (but not as much). I ended up changing the oil with Diesel 15-40 oil. The viscosity is thicker and less likely to leak past rings, but it's still within the specs for Tercels in most climates. Diesel oil also has extra detergents so it helps to clean out old gunk. After driving around with that oil in my van for a couple of weeks, the smoke went away. If you're burning so much oil that it's leaving an oil puddle under the exhaust, is the level on the dipstick going down pretty quick?
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