2011 Prius Valve Cover Photos

Originally Posted by 2015_PSD
Originally Posted by ekpolk
And, to get back squarely on topic, the OP's pictures just cemented my decision to switch from the AFE 0w-20 to the EP on my new car. I don't think that the AFE will do any harm, but this is essentially the same engine I have, and I like what I see here!
Unless you are going to run the EP much, much longer than the AFE you will see ZERO difference except your wallet being lighter. I ran 0W-20 AFE and 0W-20 EP in my 2010 FX4 for up to 18K miles and the AFE performed better (via UOA results) than the EP did. YMMV.

I can't find your M1 EP UOA. Do you have the link?
 
Originally Posted by caprice_2nv
Around here all the Camry Hybrid cabs sound like they are rattling their brains out with detonation when they drive by. I haven't noticed it on Prius cabs though. Probably 60% of our cities cabs are Camry's, the rest are either Prius, vans or impalas and then some misc.

I've been kinda noticing that too - it's a timing chain rattle which the 2nd gen Prius can also develop. Before Uber and Lyft signed deals with Hertz/Avis, the Prius and Camry Hybrid were the de facto cars for those and I would hear a rattle when a cabbie or Uber passes me in SF. I also hear it from privately owned examples as well. I've heard timing chains are a fact of life on the 1NZ-FE, but a 2AZ-FE shouldn't develop a rattle.

I'm thinking the nature of a hybrid is causing the chain to prematurely load up or slacken when the engine is off but the motor-generators are spinning. But if MG1 is always moving with the crankshaft(unless the planetary gear that's the power-split device mechanically disconnects from the engine), as long as there's oil pressure from a spinning oil pump, the timing chain tensioner should exert pressure to keep things taut.
 
Originally Posted by The Critic

Originally Posted by cpayne5


What made it difficult? Not much slack in the chain to work with? Looks like all the appropriate marks are in place.

I've done a few Toyota chains, but never one on this engine.


I should have set TDC manually. When you follow the directions by toyota, they ask you to rotate the engine until the colored links match up with the marks on the cam gear and/or the phasers. This can take many many revolutions.


Ah, so no alignment marks on the block or head?
 
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meh high miles on a prius is not like high miles on a all gas car. Electric motor does the off the line accelerating (the low end stuff) and its purposely kept at low rpm for its engine size for fuel efficiency (the top end stuff) so it A. SHOULD look excellent as it does not work hard at all and B. should not be blowing head gaskets given its light duty and partial use.
 
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Originally Posted by stanlee
meh high miles on a prius is not like high miles on a all gas car. Electric motor does the off the line accelerating (the low end stuff) and its purposely kept at low rpm for its engine size for fuel efficiency (the top end stuff) so it A. SHOULD look excellent as it does not work hard at all and B. should not be blowing head gaskets given its light duty and partial use.

That's a point well-taken. Also, though it probably doesn't have much to do with the cleanliness of this engine (or any other), these engines have yet another longevity trick up their sleeves: they essentially have a built-in pre-oiling feature. Not an old fashioned "pre-oiler" like you could add to an engine, but it's inherent to the design. Every time the computer decides to start the ICE, it spins it up briefly before adding fuel and spark. In other words, on every engine start, the oil pressure is up (or at least climbing) before the real action starts. No way to tell how much difference this "feature" makes, but I believe it's substantial.

As for the head gaskets, well, like a problem on any other engine, Toyota needs to get its engineers back to the drawing board (or CAD computers or whatever they use now...) and figure that out!
 
Originally Posted by ekpolk
Originally Posted by stanlee
meh high miles on a prius is not like high miles on a all gas car. Electric motor does the off the line accelerating (the low end stuff) and its purposely kept at low rpm for its engine size for fuel efficiency (the top end stuff) so it A. SHOULD look excellent as it does not work hard at all and B. should not be blowing head gaskets given its light duty and partial use.

That's a point well-taken. Also, though it probably doesn't have much to do with the cleanliness of this engine (or any other), these engines have yet another longevity trick up their sleeves: they essentially have a built-in pre-oiling feature. Not an old fashioned "pre-oiler" like you could add to an engine, but it's inherent to the design. Every time the computer decides to start the ICE, it spins it up briefly before adding fuel and spark. In other words, on every engine start, the oil pressure is up (or at least climbing) before the real action starts. No way to tell how much difference this "feature" makes, but I believe it's substantial.

As for the head gaskets, well, like a problem on any other engine, Toyota needs to get its engineers back to the drawing board (or CAD computers or whatever they use now...) and figure that out!


You are probably right about the looks (varnish and so forth). The low work load might actually do more to contribute than keep it clean BUT they should definitely last a lot longer than conventional use engines given their work load and aforementioned pre-oiling which I wasn't aware of (wondered how that frequent stop/stop stuff could not be harmful to longevity, now I know lol).
 
Originally Posted by nthach
... I'm thinking the nature of a hybrid is causing the chain to prematurely load up or slacken when the engine is off but the motor-generators are spinning. But if MG1 is always moving with the crankshaft(unless the planetary gear that's the power-split device mechanically disconnects from the engine), as long as there's oil pressure from a spinning oil pump, the timing chain tensioner should exert pressure to keep things taut.
MG1 is not "always moving with the crankshaft." The planet carrier is. MG1 is always moving with the sun gear. The ring gear and MG2 always move (at fixed ratios) with the wheels. Nothing in the "power split device" disconnects; there are no clutches, brakes, or synchronizers anywhere in the transmission.
 
Originally Posted by Gokhan
Originally Posted by 2015_PSD
Originally Posted by ekpolk
And, to get back squarely on topic, the OP's pictures just cemented my decision to switch from the AFE 0w-20 to the EP on my new car. I don't think that the AFE will do any harm, but this is essentially the same engine I have, and I like what I see here!
Unless you are going to run the EP much, much longer than the AFE you will see ZERO difference except your wallet being lighter. I ran 0W-20 AFE and 0W-20 EP in my 2010 FX4 for up to 18K miles and the AFE performed better (via UOA results) than the EP did. YMMV.
I can't find your M1 EP UOA. Do you have the link?

Well, you don't even seem to have posted your M1 EP 0W-20 UOA. You mentioned you would run it considerably longer and your iron was already rising between your UOAs; so, whatever you saw probably didn't mean much.

https://www.bobistheoilguy.com/foru...78641/2010_FX4_%7C_M1_AFE_0W-20_%7C_15,1
 
Originally Posted by Gokhan
. . .
Well, you don't even seem to have posted your M1 EP 0W-20 UOA. You mentioned you would run it considerably longer and your iron was already rising between your UOAs; so, whatever you saw probably didn't mean much.

https://www.bobistheoilguy.com/foru...78641/2010_FX4_%7C_M1_AFE_0W-20_%7C_15,1


Easy guys. Just got off the monthly mods conference call. There is an anomalous setting in the UOA sections. You may need to drop down to the bottom of the page, and reset the "Show From Previous" window from three months to " all threads". If you don't, you'll only be searching three months worth. Wayne will be getting this fixed shortly. Apologies for the inconvenience.
 
Originally Posted by stanlee
meh high miles on a prius is not like high miles on a all gas car. Electric motor does the off the line accelerating (the low end stuff) and its purposely kept at low rpm for its engine size for fuel efficiency (the top end stuff) so it A. SHOULD look excellent as it does not work hard at all and B. should not be blowing head gaskets given its light duty and partial use.
ALL the energy consumed by the motors comes from the engine, whether it's supplied simultaneously, or after being stored (in small amounts) in the battery. In other words, all the energy to power the car comes from the engine.

I will agree that a 98-hp, 1798-cc engine shouldn't be blowing head gaskets, though!
 
Originally Posted by ekpolk
Originally Posted by Gokhan
. . .Well, you don't even seem to have posted your M1 EP 0W-20 UOA. You mentioned you would run it considerably longer and your iron was already rising between your UOAs; so, whatever you saw probably didn't mean much.

https://www.bobistheoilguy.com/foru...78641/2010_FX4_%7C_M1_AFE_0W-20_%7C_15,1
Easy guys. Just got off the monthly mods conference call. There is an anomalous setting in the UOA sections. You may need to drop down to the bottom of the page, and reset the "Show From Previous" window from three months to " all threads". If you don't, you'll only be searching three months worth. Wayne will be getting this fixed shortly. Apologies for the inconvenience.

Thanks, that helps.

This is his only and last UOA with M1 EP 0W-20, after which he sold his truck.

https://www.bobistheoilguy.com/foru...78641/2010_FX4_%7C_M1_AFE_0W-20_%7C_15,1

It's very similar to his previous UOA with M1 AFE 0W-20, despite running well over 15,000 mi this time. The only difference is the higher TAN but that can mean a lot of things, such as having exceeded the oil's life. There is no reason to expect the AFE to do any better in similar conditions, given that it has an inferior base oil and lighter additive package.
 
Originally Posted by CR94
. . .

I will agree that a 98-hp, 1798-cc engine shouldn't be blowing head gaskets, though!

Gee, I guess I'm safe -- in its 2018 trim, it's only 96-hp now! But the electric motor is 71-hp -- all the more reason that gaskets shouldn't be blowing. Seriously though, gaskets shouldn't be that hard to get right. For those who doubt this, I have a one word rebuttal: Fel-pro.
 
Originally Posted by ekpolk
CR94 said:
. . .

For those who doubt this, I have a one word rebuttal: Fel-pro.

And Fel-Pro has a good track record for problem children. If I had to do one, I would use a PermaTorque MLS.
 
Originally Posted by nthach
Originally Posted by ekpolk
For those who doubt this, I have a one word rebuttal: Fel-pro.

And Fel-Pro has a good track record for problem children. If I had to do one, I would use a PermaTorque MLS.
Toyota has a new, improved head gasket, used in later 3rd-generation Prii. Too late. Of course they don't admit the early version was defective.
 
Originally Posted by CR94
Originally Posted by nthach
Originally Posted by ekpolk
For those who doubt this, I have a one word rebuttal: Fel-pro.

And Fel-Pro has a good track record for problem children. If I had to do one, I would use a PermaTorque MLS.
Toyota has a new, improved head gasket, used in later 3rd-generation Prii. Too late. Of course they don't admit the early version was defective.



They admitted it just by changing the gasket.
 
Originally Posted by Gokhan
Originally Posted by ekpolk
Originally Posted by Gokhan
. . .Well, you don't even seem to have posted your M1 EP 0W-20 UOA. You mentioned you would run it considerably longer and your iron was already rising between your UOAs; so, whatever you saw probably didn't mean much.

https://www.bobistheoilguy.com/foru...78641/2010_FX4_%7C_M1_AFE_0W-20_%7C_15,1
Easy guys. Just got off the monthly mods conference call. There is an anomalous setting in the UOA sections. You may need to drop down to the bottom of the page, and reset the "Show From Previous" window from three months to " all threads". If you don't, you'll only be searching three months worth. Wayne will be getting this fixed shortly. Apologies for the inconvenience.

Thanks, that helps.

This is his only and last UOA with M1 EP 0W-20, after which he sold his truck.

https://www.bobistheoilguy.com/foru...78641/2010_FX4_%7C_M1_AFE_0W-20_%7C_15,1

It's very similar to his previous UOA with M1 AFE 0W-20, despite running well over 15,000 mi this time. The only difference is the higher TAN but that can mean a lot of things, such as having exceeded the oil's life. There is no reason to expect the AFE to do any better in similar conditions, given that it has an inferior base oil and lighter additive package.
Really? Well, first of all, there is not a single UOA of EP in the link that was posted, so once again you are making assumptions as you tend to do. Next, iron always tracks higher as mileage increases on an OCI, so not sure what you are attempting to state by saying it was rising--it can do nothing BUT rise and 20-22PPM of Fe for a 15-18K mile run is fairly trivial, when noting there are plenty of UOAs that have as much or more at far less miles. Lastly, considering that AFE did JUST AS WELL as EP pokes holes in your frequently stated baloney about inferior base oils--seriously man, your bovine scatology runs deep on this board. Here is the full list of UOAs for the truck -->2010 Ford FX4 UOAs. Do tell us how EP was "better" and how AFE is inferior in my use case and try not to bore us to point of wanting to stick a pen in our eyes by posting a dissertation of convoluted nothing.
 
Originally Posted by StevieC
Look at all that carnage from a 20wt. My god man you should switch to a 0w40 immediately.
lol.gif



Thanks for posting.
thumbsup2.gif



Originally Posted by Snagglefoot
That must be a typo. You can't get 185,000 miles on 0w20!
lol.gif



Don't forget, it's a hybrid and so the engine isn't running all the time... so it doesn't really have 185k...
wink.gif
 
Originally Posted by JHZR2
Originally Posted by StevieC
Look at all that carnage from a 20wt. My god man you should switch to a 0w40 immediately.
lol.gif



Thanks for posting.
thumbsup2.gif



Originally Posted by Snagglefoot
That must be a typo. You can't get 185,000 miles on 0w20!
lol.gif



Don't forget, it's a hybrid and so the engine isn't running all the time... so it doesn't really have 185k...
wink.gif



While I'm not aware of the whole subject, I wanted to bring up the fact that I have a hybrid that has been running 0W-20 for 457k miles, and that most of my driving is highway driving, so the engine is running a lot more than some may think. I would put it at 90% of the time, as most of the roads I travel are above the maximum speed the car can run in EV mode.
 
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