2008 head gasket replacement

I relatively recently replaced the gasket on a 2009 and I FAILED (coolant still leaks into oil). One thing I would do differently is take the head to a shop for resurfacing. I got quoted "about $60-70".
I personally would not buy a refurbished head unless it comes with both cams, otherwise getting correct valve clearance could become an expensive hassle.

 

The head bolt socket is NOT triple-square nor XZN. It is dual hex aka bi-hex size 8mm and you need one that is longer than a typical bit. Performance Tool W83184 Extra-Long Double Hex Head Bolt Sockets for Toyota Engines, 2 Piece, 8mm and 10mm Sizes, S2 Steel worked great. $18 regular price from Walmart. It was shipped, I don't think stores carry it, but I'm not sure.

I used the Felpro the 1st time. The gasket looked good and I don't suspect the gasket at all. This time I ordered a Mahle for no other reason than that it shipped from the same Rockauto warehouse as stuff for other vehicles. The Mahle seemed to resemble the head gasket that was on the car (I don't know if factory original) more in some details, but I have not compared. I don't suspect that the gasket had anything to do with what went wrong.

The timing chain cover has a water passage, so pay attention to get sealant everywhere it's supposed to go.

I didn't touch the inverter other than set the inverter tank aside. Moving the inverter housing would have made accessing stuff on that end of the head a bit easier but was not necessary. 90 degree pliers helped with hose clamps.

 

I have had my 2009 about 60k miles and I'm not aware of any overheating during my ownership.
(Only unusual engine issue I had was intermittent misfire caused by a faulty NGK spark plug from rockauto, so not supposed to be a fake like one can supposedly easily get from ebay, amamazon, etc).
I plan to definitely check the head much more carefully for cracks, because I felt that the procedure went well but it didn't fix the problem.
My cooling system holds 15 psi for days, but as soon as combustion forces are present, coolant mixes into oil, even on a completely cold engine, so coolant is not yet at anywhere near radiator cap pressure.

 

You should be able to get a one NZ head w cams valves adjusted and set etc about 400. I did same w 1zz the guy said he could 1nz for Prius . He did a bang-up job on the ones easy look like a brand new head and I'm sure the Prius will be saying that was delivered .!

 

Yep, Performance Tool W83184 is correct. And yep Rockauto has it incorrectly described as "triple square".

 

Rocauto also has this wrong: "Use the 8mm on models up to 2006, and the 10mm on models 2007 to current", at least when it comes to Prius.

 

Just in case, your parts list didn't mention head bolts (but could have been included under "etc")... The head bolts are torque-to-yield and are not to be reused.

 

BTW, the link lists both Prius and other models for the same head.
Prius camshafts (or at least intake for sure, probably exhaust too) should be different from the rest.

 

I'm curious what people here think about Prius timing chain replacement at 125k?
Personally would just inspsect, including guides and tensioner, and let it ride if it looks good (unless I thought that what's in there is a no-name ebay special, which is probably very unlikely).
Depends on what "prolonged overheating" means... Maybe replace guides as a precaution?
I recall hearing somewhere that if the 3 timing marks on a Toyota chain have disappeared, it has overheated? Any truth to that or is it an old wives' tale?

 

Yeah, no vehicle should be sold without an honest oil pressure and coolant temp gauge.
By honest I mean one that hasn't been "Nerfed" so that it reads outside of normal range only after it's already too late.