1996 unused for 4 years

couple recommendations,

keep track of the dowels on the cams, they come out easy and are a MF'er to find in the dark

coolant in the forward most passages is ok, those are coolant passages. the big roundish ports is where you don't want to see and liquid

that big grey wire harness in the center, thats for knock sensors, DO NOT hit those with anything, use no impacting tools near them. I recommend ordering that harness ASAP before you reassemble and install as you reassemble. if not, the odds you'll have a knock sensor code after are pretty high ( age and heat make wires and connectors brittle) there is also a short wire that connect to the temp sensor, get that too.

if you do not have a 12mm 12pt socket, get one NOW, you'll need that to pull the head bolts, they aren't stupid tight ( if torqued properly previously ) and a decent 3/8" ratchet will get them

the Cam gears, DO NOT pull the cams without locking the gears ( the intake cam is a double gear, the skinny side is spring loaded ), if you look there is a place to install a bolt thru gear to keep them aligned. I learned the hard way.

don't reuse the head bolts, they're cheap compared to having to redo the job

I'll post more as I remember

 

Thanks for the tip on the dowels, knock sensor and temp wire. I'm not using any impact tools, this is a budget job. I am replacing the head bolts though.

I don't know if you can buy anything six point anymore, except for my deep wells I can't find any six point sockets or box end wrenches. Where can I find some? I did go out and buy the nicest 12 point 12 mm I could find for the head bolts.

I wonder if I should hit my electrical connections with dielectric grease before reassembly? Also how bout this anti seize, should I use this on exhaust hardware sparingly?

And I watched a video on the cam removal, I wonder if that's where my missing valve cover bolt went.

 

ha, yeah, I ment 12mm, I've got buckets of old tools and partial sets I've acquired or thinned out, all that crap and I had to BORROW a 12mm 12pt Thanksgiving morning last year, I now own 3. I hate 12pt sockets.
You can get 6pt, but you have to buy them in rail sets, rarely to they come in a kit. My favorite goto set is a mid length set I got from MATCO 10years ago, I use them damn near daily. have replaced a few due to wear, thats the advantage of buying off the tool truck, no questions asked warranty.

Cam gears, thats exactly what I used on my gears, valve cover bolt. they're handy and it works.

IF you got the exhaust stuff off without issue I'd leave alone, the studs if they stayed in the head, have probably backed out a but, tighten them down before you install the nuts, or you'll pull them out of the head fairly easy. do re-squish the nuts so they stay tight on the studs ( place nut crown up and pop with hammer to mash top a bit )

the connectors seal fairly well, dielectric grease probably won't hurt but the heat could melt it out and cause the residue to collect dust and dirt.

 

The exhaust bolts and studs were never heat cycled. They were removed 4 years ago for the alleged failed headgasket job, and I've probably put 30 miles on it since it's been overheating. They came off easy. I just want to be able to get them off later as ill likely be taking things apart again.

I'll be taking a picture of the old headgaskets while the heads are off, hoping someone will chime in if they see a problem.

Good idea on the exhaust bolts, problem is four of the bolts I took off on the right side are not oem. They look like car quest specials. So at some point I'll be replacing with oem.

 

RH head is off below are pics of the oem headgasket and its proper orientation above the deck, and above the deck with the non-oem headgasket.

brb - taking off other side.

 

those gaskets don't seam to match up all the holes they need.

in fact I would say by looking at it that they were put in on the wrong side, just look at the 2 water holes in the bottom front and the gasket has the two matching holes for it in the back so its either on the wrong side or the gasket is not using the right hole pattern for your engine.

notice the small hole on top or rear cylinder will be blocked by the gasket, also the two slots in the front of the head are completely blocked by that gasket as well. its clear to me that the gasket was the problem.

 

^^^^^^ Yes, looks like wrong model gasket. Where is this from. I hope it was an OEM manufacturer, dont start skimping now that youre this far along.

I need to tell you right now. You need to take those heads to a machine shop, and have them pressure tested and straightened. If you dont, your next thread will be titled: "Just spent $xxxx on a head gasket and still overheating"

Make sure that block surface is clean enough to eat off of before you place the head. Use a razor and/or green scuff pad, lots of brake cleaner. Get as much of the debris out from piston edges, dont want metal scrapings scratching the cylinder bore. We would use extra thick assembly lube on the piston edge to prevent stuff from falling through.

 

Yep, your head gasket was on the wrong head. Notice on the left, the extra round hole that is just showing the block deck surface? Above the rectangle hole.

Pull off the other head and you will find the passage that needs that hole .

 

That "extra" round hole is an oil drain from head to bottom of block. Look at first page at my pick you will see where my OEM gasket with 200k is in same orientation. The newer gasket has drain hole in it.

 

The round hole above the rectangle hole is a coolant passage for the left side of the block, it is unused on the right side. The gasket will block it on the other side. The rectangle hole is the oil drain, along with the 3 other round holes near the outside of the block.

 

RH head is off below are pics of the oem headgasket and its proper orientation above the deck, and above the deck with the non-oem headgasket. It appears that this side had a port blocked on the front end of the deck, right above the thermostat (left most portion of the head in the bottom image). I am taking this as an indication that the headgaskets were put on backwards (left gasket on right side, right gasket on left side). I checked for a L or R on the old gaskets but there was no indication.

BONUS: I found my missing valve cover bolt, it was inside a well of the head next to bolt #3. I think this was a oil well (where oil is pumped up through the head. My guess is the shade tree mechanic who replaced my cylinder head, left the bolt in the exhaust cam sub gear. It worked its way out and thankfully found a resting place in that well. I wonder if it ever floated around in the oil port, it looks like it would have fit well - all the way down through the block.

NOTE TO SELF: never, ever, ever let someone without liability work on your vehicle. The guy who worked on this for me was a friend and I didn't want to create any bad blood, so it is what it is.

 

So where is the new gasket from? Please tell us the heads are at the machine shop getting inspected.

 

The gasket residue on block deck, is that from current removed gasket or from the gasket it replaced ? For not having been run that deck looks like crap

 

agreed ^^^^^^^^^^^

your friend never properly cleaned the surface before installing the gasket. discolorations are fine but it looks like we are seeing some sort of gasket material still there from the oem gasket he removed. you were lucky it didn't have any compression leaks.

clean it up very well and make sure you use genuine oem Toyota head gaskets this time and that every hole or passage has a matching hole for it in the gasket.

as to bringing the head to a shop and all that, since you had good compression its not something you "need" to do but it would be a good idea if you can afford to do it and have the heads reworked and made new again. after all, the idea is for this engine to last you another 300k miles after you get it back together right? a few hundred dollars spent to rework the heads would be a good investment if they were never redone the last time

 

all holes lining up or having a corresponding hole in gasket isn't going to happen, not all the holes are cut in the gasket, and some of the smallest are more for air pocket relief than actual coolant flow.

having clean, slightly rough deck is the most important, clean head bolt hole as well, chase with a tap and lightly lube threads on head bolts and washers as you assemble. the more consistent you can make the head bolts tighten, the better seal and clamp you're going to have in the end.

Dot the edge of each head bolt so you know where 90° is from start point, try to achieve each 90° in one smooth motion.

 

I would also add, looking at the pics at the top of the page, you should use a whole bottle of simple green on the engine bay and pressure wash it down.

 

http://www.northerntool.com/shop/to...NBMz-FM67vLeq2dcHoCa9vt-0Q8ajM3C4GBoCLuTw_wcB

Snag one of these at a body shop supply or Home depot. Grab several of the 150-200grit precut strips,,,the tool tells you what to do. You can scuff those flat surfaces with it,,to check for cracks before they go in. Once scuffed, you can straightedge the heads,,to check for warp and a machine shop then if so. Be gentle with it till you get the tool time.

 

Head gasket is toyota oem. Had to take the first oem headgasket back cause it was damaged.

I used a starrett straight edge and 0.10mm feeler gauge to asses head warpage, per the manual. "If there is warpage replace the head"

No warpage, head not replaced.

The truck was ran after the first headgasket "swap", but every time it ran it approached overheating so maybe that has something to do with it looking like crap. There was plenty of gasket residue (graphite?) to clean up, I used plastic gaskets scrapers on the aluminum, and razor blades on the block. I also used acetone repeatedly and made sure the surface was "smooth".

I made sure to leave the old head bolts In their threads while cleaning the deck so I didn't introduce a bunch of new debris to those threads. I also blew out the bolt holes with compressed air and acetone (translation: carb cleaner).


I'm also following the Toyota FSM, so I'm using dots for referencing 90 degree turns as well, and a torque angle meter (lisle).

Thanks for all your interest, I'll let you know how it goes. All advise is appreciated.