I am very sorry for the late response. My computer crashed and my life has been upside-down for the last week. I've resolved my computer issues and everything is up and running again
. I somehow managed to go about 5 or 6 years without any problems, but the last few months I've made up for it. I finally just went out and got a laptop and of course I had to have something unique......yadda yadda........okay so I'm rambling, sorry. If anybody's interested I made some posts on the HP forum
HERE.
Okay, back on topic. You mentioned you purchased a head gasket kit? You got a genuine Toyota gasket set right? There is a wide varience in quality when it comes to aftermarket head gaskets, so unless you're feeling lucky you should stick with Toyota here.......just saying
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The valve grind gasket kit for the 4y is Toyota Part #04112-73035. There have been different numbers used for this same kit over the years, so don't be too surprised if that number is superseded by another. As for hoses, I don't like flex hoses and will only use them when there are not other alternatives. I consider formed hoses to be far superior. There are a lot of formed hoses in the engine compartment. Most are still available but some are not. Last time I ordered these Toyota substituted some straight hoses for some of the formed coolant hoses. I ended up taking these back because why pay $15 for a piece of 18" straight 5/8 heater hose???
For the ones that are still available I marked up these break-down sketches from the EPC with part numbers. If I say "use bulk hose" it means you will either get bulk hose from Toyota at a very high price, or it is NLA (No Longer Available). For some of the smaller 5/16" hoses I found that Gates hose is actually superior to factory Toyota hose so I marked this up to show the locations this will work in. Some of the others are bent too sharp (bulk hose might kink) so I listed Toyota part numbers for those. There are some slight differences from 2wd to 4wd on some of these hoses so if you order make sure you copy down the correct part numbers.
Note 1: The EPC lists this hose as #99556-20300 for 2wd and #87245-95D12 for 4wd. The last time I ordered the one for 2wd Toyota sent me a hose in a package with the correct part number, but it was actually a 12" piece of 1/2" ID straight hose (not formed). So for this one I say save your money and just get a piece of 1/2" bulk heater hose for 50 cents (Toyota charged me $13). I'm not sure what you'd get if you ordered the 4wd hose, but it wouldn't surprise me if you got the same thing.
Okay, here's the air valve hoses and the ventilation hoses for the valve cover. The last few times I ordered the PCV grommet from Toyota there was a problem with the part number, but I found Dorman makes replacement ones that fit nice. Dorman has the racks marked "HELP!" in the retail section of most auto parts stores. You will find several rubber parts like this there, just use the part number in the picture below to identify the correct one.
Note: Rubber line (not shown) that goes from intake manifold to the metal line on firewall (brake booster vacuum supply) is Toyota
#44774‑28080
Okay, last but not least is your BVSV (Bi-metal Vacuum Switching Valve) otherwise known as the "Oh crap I broke it valve". The plastic nipples on this valve get extremely brittle from the heat of the engine compartment and will break off if you look at them wrong. If you're pulling the head it's almost a given this valve will break. Last time I purchased one was about 2 years ago and at that time they were still available through Toyota. The valve's mission in life is to inhibit EGR operation when the engine is cold. These run about $40. Here is a picture of one.
As for your question regarding flushing out the lower end, I would advise against that. Nobody likes the idea of heavy sludge or chunks of scale floating around down there, but unless you tear down the bottom end, other than changing your oil there's not much you can do. Using crank-case flushing products on old engines is a bad idea. Scale or build-up doesn't do any harm when it's stuck to an engine surface. If the cleaning product actually works it will only serve to move the gunk from it's harmless position into a potentially bad one. When this stuff floats around in the pan it will typically end up stuck to the oil pump pick-up screen and if enough of it gets deposited there it can starve your engine for oil.
Chances are whatever fell down there during head removal will eventually drain out during an oil change or it will find a harmless place to deposit itself. Just try to minimize any further contamination and you should be okay. Tim