2008 Toyota Prius piston soak

Welcome to Priuschat !!

Glad to hear you're having success, and thank you for posting your piston soak experience.

How many miles are on your vehicle?

What oil type (dino/synth) and weight do you use?

How did you remove the MMO after you were done letting it soak?

On the average, what speed to do drive on the freeway / interstate?

Was there a reason you chose MMO over something stronger?

 

How many miles in those two weeks?

 

If you mileage accumulation is pretty steady, that's steep consumption: somewhere around a quart every 700 miles. Which is still "acceptable", according to Toyota...: (In the Owner's Manuals there's statement that a quart every 600 miles in the acceptable limit.)

Perhaps Toyota should note this "feature" in their sales brochures.

You squirt a measured amount of MMO into each spark plug opening? How much?

I'm thinking you could do this just before an oil change: put in the MMO and let it soak, crank the the engine over a turn or two (say with a socket on extension, reaching through the wheel well), then drain the oil, replace oil filter.

Yeah, please post an update in a few more weeks: the more miles you pile on, the more accurately you can determine the oil consumption reduction. Sounds like a relatively simple procedure to do, btw.

 

Marvel Mystery Oil... That stuff... Back in 92 my Mazda RX-7 Rotary engine had all the signs of blown seals... So I sold it to a guy who raced rotary engines for a few hundred bucks. He poured that stuff into the engine and drove the thing away. A very humbling experience. What is it about that stuff?

 

I had success with Marvel Mystery Oil in the past freeing stuck lifters on my wife's 1960 Buick.
I makes good air tool oil also.

 

I do hope that sorts out any mechanically induced cause of the oil shortages.

 

Any more updates on your oil consumption?

 

How many miles post-treatment now?

 

I've been adding MMO during oil change, as per MMO's instructions: 20% replacement to oil, so that's about .75 quart or just about a quart for my 2005 Prius. I have not seen much success in stopping oil consumption. I am afraid of pouring liquid stuff where the spark plugs sit due to my "very expensive experience" where once my car engine was knocking and had to tow it to the dealership and $ 1100 repair later... it was water that had leaked thru the aging seals somehow. So if I understood this thread correct: a piston soak is where we pour MMO via the coils/spark plugs and let it sit there overnight?
Then do we attempt to start it the next day by putting the spark plugs back in and drive normally? or do we attempt to start without the plugs to clear the MMO out? or should I use my oil pump to suck out MMO before starting?

Original Owner of 2005 Prius
2nd owner of 2006 Prius
265,000+ miles and driving....

 

If you try to start the car with too much oil in the cylinder you will hydrolock the cylinder and bend a rod ruining your engine. Inspect each cylinder for liquid content, hopefully it soaked down by the rings and that is where you want it to go. On a normal car I would crank it over to be safe.

 

100% true. Old Porsche 356’s had a bad habit of hydro lock if you didn’t close off the fuel valve on the gas tank. The tank was above the height of the carb and under the right conditions gas would partially fill a cylinder, someone hits the starter and boom, broken crank.

I don’t think the OP ever mentioned how much he put in each cylinder. Either way personally I would suck out as much as I could before starting the engine. Whatever good it did would have occurred by the oil leaking past the rings I would guess.

 

That’s great news. Are you putting the MMO in the fuel now? How much did you put in each cylinder to start?