Ali SC3

iTrader: (10)

probably didn't have coolant behind it my guess if its that mid to dark brown tarnished color then there is oil behind there and it wouldn't rust out if there is oil protecting it so it makes sense, its probably where the oil collects after being squirted higher on the head or its just a crank case passage as you said. I definitely wouldn't fill it and seal it, if coolant is supposed to go in there it will go in there when you fill it.

how hard is removing and replacing those plugs? any tips for others who might have to do it?

apsykes

Freeze plug, figure a way to remove it, and get a new one, via dealer or auto parts store

Install: make sure surface clean, hit new one in flush (too much in and itll fall into the head)

CLRH2O

Removing the Freeze Plus is actually very easy.

All you need is a hammer (or mallet) and a flat edged punch. In my case I used the metal part from a Buck Bros screwdriver (there's a very good chance you have this screwdriver!) with the larger flathead attachment in place.



Anyway, you take that and put it up against the outer lip - tap on it in the same spot until you make the plug flip (or "eyelid" as one tutorial video I watched said) and you can then use a regular pair of pliers to pull it free from it's socket.

Once removed, use something to clean up the mating edge of the plug hole. In my case I used the metal cleaning wheel from a Dremel set and a the Dremel to sort that out (be careful to just lightly clean the edge - not grind away any of the metal)

To install the new ones I used a 19mm deep well socket wrapped in a blue rubber nitrile glove and pushed into the indentation in the center of the new plug - then tapped it into place with a hammer. Since, there are two identical plugs on the front of each head, you can use the other one right beside it as a template of how far to tap the new plug into place.

Really, once you get started with them - you'll discover it's a rather easy process

CLRH2O

Hey everyone - I'm back with a follow up on all of this

Ali - turns out you were right - the top freeze plug in the 1UZ-FE heads is for gas exchange throughout the valve system. The bottom Freeze Plug is for coolant passageways. So, for all those with rusting out freeze plugs in your HEADS - you only have to replace the bottom ones. The tops will be fine as no coolant ever touches them.

As for the rest of it - well, I know how to do a full timing belt and water pump (and hydro-fan, belt tensioner, misc pulleys and everything else that's involved) job on the 1UZ now!

In my personal experience - I would have to say the worst overall part of this entire process was removing the top rear bolt from the AC compressor in order to move the unit down enough to slide the Hydro-Fan off it's bolt that sits *right* below the AC drive pulley's lip. ARG - WHO DESIGNED THAT! The top rear bolt is in the absolute WORST location with essentially zero space to work a ratchet and socket. I had to use an angle socket and blind luck for about an hour (spread across two days out of frustration) to get it loose enough to move the AC compressor down about a 10mm so the fan pump assembly could be removed (and returned).

Also, messing up your timing is a VERY REAL possibility. I did it. I mean, just straight up messed it all up as wildly as you possibly can. Luckily - getting it back into correct alignment isn't soooo bad - given that you have the cam pulley SST (or something that works like it). The thing I didn't know about the cams is that you cant just rotate them to exactly the place you want because they are spring loaded. This may seem obvious to anyone who rebuilds heads and valves / lifters ect. But for me, I wasn't - and I simply could NOT figure out what was *binding* and spring loading the cam shaft - until I had that "DUH!" moment when I thought about what the cam shaft is actually attached to and doing inside the head when being rotated. Anyway, using an SST while putting on the timing belt is key so you can counter act that spring loading and get the pulley teeth and TDC marks into the matching belt marks locations.

So, there's a little follow up on what could have been a cracked head - but turned out to just be a rusted out freeze plug.

Moral of the story? ALWAYS USE TOYOTA RED ANTIFREEZE! (holy crap what an escapade!)



This has been a loooong learning process. And there are definitely stumbling blocks along the way if you're doing it alone working only from forums, the PDF service manual and misc online tutorials such as these great ones:


http://www.lexls.com/tutorials/engine/timingbelt.html

https://www.clublexus.com/forums/sc-...t-removal.html

http://www.lextreme.com/timing2.html

http://www.lextreme.com/timing.html

This is technicaly for the 2U and 3UZ - but it's nearly exactly the same thing and was immensely helpful:


Now it's time for a new Alternator, Grounding Kit, BFI 3.4 (maybe even the BFC for the heck of it ;D ) and NEW EXHAUST! woohoo

Ali SC3

iTrader: (10)

Looks like you have had a real learning experience. great it all worked out and is back together, the difference in the freeze plug condition gave it away. I second the toyota red, there is something to it. All my toyota's that I care about get toyota red. no questions asked.