In a standard oil pump in something like a Toyota can oil flow back trough the pump into the pan when the engine is off?
Oil pump
- Thread starter Lonnie
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If it's a SOPUS product.
Oil cannot flow through an oil pump in a Toyota when the engine is not running.
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Mokanic - now you should learn early on ..you can't just say that the cat died. We need the full Monty here.
I mean the word "Toyota" spans many decades ..and I'm sure that they didn't just use one pump design over that time. Japanese engine designers weren't stuffy on swapping philosophies in mid-stream crossings (never cross the streams
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I mean the word "Toyota" spans many decades ..and I'm sure that they didn't just use one pump design over that time. Japanese engine designers weren't stuffy on swapping philosophies in mid-stream crossings (never cross the streams
no. first when an engine is off there is no oil flow. 2nd, the filter has an anti drian back valve which prevents flow to the oil pan.
the pump picks up the oil in the oil pan which goes through the pump, then through the filter then though the bearings and engine. when it gets to the top, if flows back to the oil pan and starts the cylce all over again.
here is pic showing how it works.
http://rwinters4.photosite.com/~photos/tn/7160630_348.ts1166802990000.jpg
the pump picks up the oil in the oil pan which goes through the pump, then through the filter then though the bearings and engine. when it gets to the top, if flows back to the oil pan and starts the cylce all over again.
here is pic showing how it works.
http://rwinters4.photosite.com/~photos/tn/7160630_348.ts1166802990000.jpg
Is there enough clearance in an oil pump to let a little bit of oil flow back through the pump with the engine is not running?
I recall a warning that when changing one's oil they shouldn't let the car sit empty and filterless overnight, lest the pump "lose its prime".
I know on a saturn gerotor pump, built into the timing cover, you're supposed to put vaseline in it whenever you have the cover off.
What Bob says about ADBVs is of course accurate, so the "system" should not drain down as long as everything's working properly.
I know on a saturn gerotor pump, built into the timing cover, you're supposed to put vaseline in it whenever you have the cover off.
What Bob says about ADBVs is of course accurate, so the "system" should not drain down as long as everything's working properly.
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Oil pumps do drain back ..ADBV don't always hold ..no clearance is perfect. If an oil pump doesn't leak one direction or another ..then it's some specific design feature that breaks the natural siphon effect of fluids seeking their own level. In the rotor type pumps, the residual oil in them will provide the seal upon startup. That's why the petroleum jelly is needed for the first startup (there is probably a cache area in the pump that always has oil in it that you evacuate when removing the cover that coats the vanes/rotors) .
Some Land Rovers recommend changing the filter and sump in sequence and not together. That is, drain the oil ..refill the sump ..then change the filter ...or maybe the other way around - just so the filter isn't changed while the sump is also empty. They want that hydrostatic pressure there to prevent cavitation of the system ..at least beyond some level
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Some Land Rovers recommend changing the filter and sump in sequence and not together. That is, drain the oil ..refill the sump ..then change the filter ...or maybe the other way around - just so the filter isn't changed while the sump is also empty. They want that hydrostatic pressure there to prevent cavitation of the system ..at least beyond some level
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As far as I know, in a gear oil pump, which has two spur gears meshing inside a housing, due to the high placement of the inlet and outlet on the pump, about half the oil pump housing will be filled with oil, even when the pump is not running. I don't know about other types of oil pumps.
I would not attempt to comment on what a Landrover or what 90% of domestics oil pumps are capable of but I am extremely comfortable in saying that a Toyota oil pump will NOT drain or flow oil when the engine is not running. I guess we can split hairs and say that maybe in a 12hr. period 2 drops of oil will flow back down the pickup tube.Maybe I should spend the next three days performing oil pump drain tests on the two 22R engines I have in my shop now.
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No ...you can just say what unique properties that this oil pump from Toyota (no specific engine mention before now- essentially meaning all years/emgines since it's been imported) has that appears to not be present in a multitude of other types of oil pumps from a vast number of manufaturers.
Why hasn't the rest of the world learned by now
You seem like a sharp wrench/tech. There has to be something to make you speak with such conviction.
Why hasn't the rest of the world learned by now
You seem like a sharp wrench/tech. There has to be something to make you speak with such conviction.
I worked for 2 Toyota dealers for 15 years. Three years ago I opened my own shop. I'll be the first to say that I don't know everything about Yodas and I have not met anyone in 15 years that does. I have learned a good bit about them (THE GOOD AND THE BAD). I also spent a couple of years working for Honda but I rely on my best friend who owns a ind. Honda repair shop for technical info on my Honda customers.
Hope all have a wonderful Christmas holiday and an exciting new year!
Hope all have a wonderful Christmas holiday and an exciting new year!
Yes, of course it can. There is no 100% seal.
A properly valved oil filter is crucial to attenuate leakage.
Unless you only start the car every 3 months or longer, I would never worry about it, though.
A properly valved oil filter is crucial to attenuate leakage.
Unless you only start the car every 3 months or longer, I would never worry about it, though.
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You too, pal
For excitement, I think I'm going to a New Years party as a horn this year.
It has a lot to do with how high the oil pump and/or the oil filter are mounted relative to the oil pan. The key is an effective anti drain back valve as well as the standard seal. I have seen the case where the oil light would stay on longer with a loose oil filter that bled down overnight.
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