Head Gasket Project: Complete (Tech)
OK. For what its worth, I've done this work and its fresh in my mind. The intent is to share some shreds that somebody else might find useful. Its boring but might help.
94 LE 4 cyl. 220,000 mi.
Gasket kit: I used Felpro. Bought the entire kit, including valve stem seals (but didn't need them). Cost about $120 ( I shopped around / no better elsewhere). Does not include the injector insulators (which some people re-use). Does include the injector o-rings.
Bolt Kit: These are stretch/yield bolts, good for one torque cycle. I bought the Felpro replacements. Save yourself pain and spring for the new bolts. $60 at Advance.
Radiator & heater hoses: It was time to replace all of these while easy to get at. Some are molded 90 degrees, with different inlet and exit diameters. RockAuto.com has them all fairly cheap.
Removing Camshafts --- easy, just follow Hanes (or the above PDF sticky manual which is better). But I screwed up the reassembly. There are a bunch of confusing timing marks on the exhaust gear. I matched /meshed the wrong ones with the intake camshaft gear and so no compression. Easy to fix, paying attention to the pictures better you can see which marks to use.
Timing belt tension --- You can do the head gasket without taking the belt off all the way. I did fine until I drove it the first time. Belt was not tight enough and you could hear it dragging agains the cover. Like somebody else said, get the timing marks where you need them and pry the tensioning pulley tight as you tighten it. That fixed it for me.
Injector Rail Reassembly: Careful here. When properly assembled the injectors are snug but can be easily and smoothly rotated in place. O-rings on top side of injectors are the most critical element. Replace them and lube with a little bit of grease so they slip/click into the fuel rail. I pinched them the first time and gas leaked badly. Had to replace again.
Original design insulators between injector and head, that click into the head firmly, don't seem to be available. The replacements look like little tires and work ok. Our Toyota tech reuses old ones, but I used the new ones. Bought the injector seal kits from RockAuto.com for $3 per injector. Comes with another set of O-rings (duplicates are in the Felpro gasket kit.
I nested the tops of each injector into the fuel rail, put the lower insulators into the holes on the head and with two hands manipulated the whole fuel rail/bolt/injector setup to wiggle the lower ends of the injectors into the head. Then bolt the 2 bolts, check for easy rotation and was complete.
Interesting Note: I think the Hanes book I have has an error in the specifications in the front of section #2(Engine) for cylinder head flatness. Hanes reads +/- 0.02 inches. Manual in sticky section, above in this forum calls for 0.002 inches, which is more what I expected. I measurestimated about 0.006 --- a real technician would have sent it off for rebuild and shave. I used it as is. If I don't thrash it maybe it will hold.
Hope this helps somebody. I'm just a backyard mechanic. Am really stoked the car works so good after I wrenched on it.
Last edited by Landseer; 08-01-2007 at 01:27 AM.
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