Engine Wear

This is true on a COLD startup, where the engine has had enough sitting time for all of the oil to drain down into the pan. For what the Prius does, there is plenty of oil throughout the system to keep all of the internals lubed. The tolerances of moving parts is tight enough to not let oil pressure bleed off instantly.

 

Another thing to consider, the electric motors spin the ICE up to about 1000 RPM before gas and spark are supplied -- lots of time to get oil all over the inside of the ICE. And the hot coolant reservoir gets pumped back in to get the tempreature up to where an ICE likes to opperate too. HSD is NOT like an electric motor bolted on a conventional ICE.

 

I would think that small fleet of Prius operated as taxi's in Vancouver, BC, would put this myth to bed. Over 300,000km and no ICE failure.

 

I'm surprised Toyota doesn't use that guy in Vancouver for their ads. I bet you could make a really neat Prius ad with his yellow taxis

 

I was under the impression that the Prius used an oil priming pump prior to spinning up the ICE? Yes/No who Knows? DanMa32???

 

I now wonder as well. A preluber would almost be necessary. The other comments don't make much sense to me. The fact that the car isn't running on spark has nothing to do with wear, the fact that it is spinning does.

 

There is no load on the engine when it is spinning. The spinning results in full oil pressure before ignition. Additional, the engine starts on two cylinders. Also, use of synthetic oil reduces wear.

 

I agree but just because there is no load doesn't mean there is no wear. This is why in an old school motor you don't just pop the coil and turn the motor over. You take out the distributor and spin up pressure via the pump with a drill. Don't know how you would do it with electronic ignition.

This, however, is probably picking nits. I'm positive whatever it is Toyo does is fine.

 

The Prius still has a mechanically driven oil pump, like any other vehicle. If you are spinning the crankshaft, the oil pump is running. If you spin up the crankshaft to a high rpm before you ignite, then when you ignite the system is fully pressurized. It helps that the oiling system tends to "store" oil in higher parts of the system so the oil pump doesn't have to fully fill the oiling system before it comes up to pressure.

 

The very first time you start a motor, you *must* prime the oil system. Although you can disable the ignition and use a bump switch to engage the starter, that can take a long time to build oil pressure. Here is how you do it on an old fashioned motor, it works well:

Before assembling the oil pump, it helps to pack it with petroleum jelly. That helps the oil pump develop strong suction to quickly prime. You also use an oiler can to squirt oil into the gallery before putting on the oil filter.

You remove the distributor and use a special oil priming tool. One end fits into the oil pump drive (Hex or slot, depending on whether it's a Chevy, Ford, or Dodge) and the other end fits into an electric drill chuck.

You hook up a mechanical oil pressure gauge to where the sender goes, then keep the drill going until you see oil pressure. At that point you can remove the tool, install and index the distributor, and it's good to go.

With things like VVT, you can spin the motor up unloaded depending on how you phase the intake valves. You can also use something as simple as a check ball and spring to keep residual oil pressure. That would be no different than how an oil pressure relief spring works.

However, this has got me thinking about the oiling system on my Prius. Anybody know if there is a spare tap along the oil gallery to hook up a mechanical pressure gauge? I'd be curious to know if I could use a mechanical gauge.