2t and interesting oil usage

[Aphox]

Started the trek from albury to melbourne on thursday afternoon. Engine had full oil, nice amber colour. So head off onto the highway and everything is just dandy.

Until around 150km's into the journey the car started feeling strage, at first i thought it was a low pressured tire but it was not consitant enough. Car was sort of pulsing forward then maintaining speed then pulsing forward again. Pedal had to be fully down to accelerate at all, but was still maintaing speed at around 80% throttle. Fuel usage went up the kazzoo as well, using around 5x what it usually does on highway.

Pull over and let the engine cool. Idle was racing between 1000-1300 (doesn't normally). Everything is fine (carby as well) except for the fact the engine's oil was well below E. No smoke was burnt (car doesn't normally either), sump bolt is in and tight, oil filter is securely in. After topping oil up the problem has not presented itself again. The only leak it ever had was minute coming from the front of the rocker cover gaskest, then being blown over the bay by the fan.

Any ideas as to what caused it? Runs fine at the moment, two days later but i'm hesitant to use it atm...

Cheers

[18rc turbo]

you dont have oil in your radiator by any chance??? Not sure if a BHG could have those sorts of symptoms in a 2T, but it is one place you didn't mention that the oil could have gone...

how was the temp gauge??

[Aphox]

I'll check tomorrow, temp held steady, it was running at ~82c so its in the perfect range. It's a little weird...

[allencr]

How much oil does "well below E..." to "topping oil up" equal & what car, model, engine is it????

I don't have an answer, as none the combination of symptoms make any sense to me.

Overfilling can create a lot of foam that'll get sucked up & burned, but there will be LOTS of smoke.

[Rodger]

Interesting,

Was it a cold morning or evening in Albury when you left? Could explain the power loss. There is another thread with similar symptoms and a couple of us reckon the carby was freezing over.

Was the sump full of oil, as it is possible that you had a false reading and in fact were reading oil plus un-burned fuel and water vapour built up after lots of "to the shops/work/school trips".

Then all the non oil stuff got burnt off on the long highway run.

Regards

Rodger

[TRAV-KE55]

A car that runs very rich and only putted round town or been a long while since a decent run a % of the oil is actually quiet often unburnt fuel, when taken on a decent run the oil gets a chance to get upto temp and the unburnt fuel will evaporate and be consumed by the pcv system, doesnt really happen on engines that are tuned properly though, it does actually sound abit like carbi freeze though like what rodger suggested, however that doesnt explain the oil consumption, check the radiator like earlier suggested, check air cleaner for oil from breather system (symptoms of worn eng or busted rings, blowbye) take two panadol get a good nite sleep and let us know if the syptoms persist!!
Trav

Edit: Rodger beat me to the unburt fuel theroy, nice work!

[Aphox]

Car has been driven almost every other day, for bursts across melbourne and at least once a fortnight it gets around 400km's on the highway. It's a 1975 TA22 LT celica with stock carb and 2t engine. There had been a freeze the night before, it was -7 but i started it up at about 3pm and headed off fine with oil amber at F. On the highway once it started getting darker and colder thats when it happened, just realised i usually don't drive highway in the dark but surely it can't hurt it? Was sitting on 3500rpm @ 110km's when occurred.

There has always been a small amount of oil (maybe fuel?) getting into the air intake,, leak in the vacuum system or something similar?

Cheers

[Rodger]

Aphox,

Yep, that speed and revs the carby would hardly be open and the enginebay and engine would not be building enough heat to warm the carby up enough to stop it freezing over. It would then not take much ice to block it and it worsens exponentially from there until you stop. Once stopped the heat soak takes over and gets to the carby enough to then balance the temperature for the rest of the trip.

If you want to alleviate this problem you would need to put the heat riser pipe back on to the air filter housing.

As for the oil problem, hmmm, perhaps the PVC system is not quiet right and the extra vacuum created as the freezing started drew the oil out and burnt it. A thought for that issue.

Regards

Rodger