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Old 01-21-2007, 12:57 AM   #6 (permalink)
midiwall
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Quote:
Originally Posted by alankenji_84 View Post
what if the paper towel gets blown out with the exhaust? does that tell me it might not be a burned valve, and if so, any other ideas.
Well, the paper towel test will only tell you if it's an exhaust valve - if one is stuck open, then there will be a vacuum at the tail pipe on what should be the intake stroke, and that's what will suck the towel in towards the pipe.

Given that you know you're losing compression, then you're looking at (in no particular order):
  • Exhaust valve
  • Intake valve
  • Rings
  • Burned piston
  • Head gasket

Quote:
how do I know if I need the heads to be machined, and what all parts do I need.
Basically, if you pull the head and find a burned valve, then the RIGHT thing to do is to have the head machined. If this is the first time the head's been off, then there will be all sorts of crap on it and it needs to be cleared out.

If you've been running with a burned valve for a while, then you may need the cylinders honed... And, of course you may need a valve or two replaced.


Quote:
Originally Posted by alankenji_84 View Post
sorry again, but any ideas about how much this valve job might set me back if I do it myself/ if I send it to a shop.
If you do it yourself, and you have access to a milling machine (or you elect to NOT do the heads) then you're basically looking at the cost of the valves and a gasket set. Figure $300 total if you stay away from Toyota's gasket sets. If you send it out, then there's some decent labor involved, and figure on at least $100/hour.

For your "scary enjoyment", lemme point you here:
http://www.yotatech.com/showthread.php?t=100924

Now, I'm not giving $$$ numbers there, but I can tell you that the cost will go up dramatically based on how far you want to strip down the engine on your own. i.e., walking into a machine shop with a head and saying "do this" is a LOT cheaper than pulling the truck into a shop, saying "I need a valve job" and then walking out.
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