New guy here so bear with me -- fan belt came apart on my daughters 04 Camry w/2AZ-FE engine, naturally it overheated, let it cool down & changed fan belt & tensioner [a side note - whoever designed the tensioner really should be shot - but that's another story]. Drove it for several days & blew the head gasket -- I know - should have changed the thermostat & antifreeze the first time. Since my garage is unheated, I'm getting old + the fact I just didn't want to do the job -- I had a good friend who is also a great mechanic do the repairs. Believe me when I say it got HOT -- so I had the head milled. Took 16 thou to clean the head, talked to a young machinist/mechanic & he said no problem -- that you could cut 22 thou & still have 60 thou clearance between valves & piston. Mechanic I have doing the work checked with the local dealer & they told him no way -- 16 thou was too much & needed a gasket shim set to do it correct. So --my question is: how much can be milled from the head without going to a gasket shim set? Thanks in advance for all the help.

 

I'm honestly not sure but I would tend to side with the dealer.

 

No clear answer on max cut.

Minimum shim thickness appears to be .020 inch. If a shim is installed the setup would now be +.003 inch.

Head resurfacing without shimming will retard engine timing slightly as the distance between cam and crank sprockets will change. Plus slightly increase compression.

If you are concerned, just add the spacer which costs around $40.

My own 2 cents is most people who resurface the head don't shim.

As the engine is apart check head bolt threads in block for signs of pulling out. This engine had a problem with a few of the threaded holes pulling out. The internet has lots of posts on this issue.

 

Engine is back together & currently running fine. Am aware of the head bolt problem with this family of engines but in this case the head gasket failed because it overheated not because the head bolt threads failed. The only reason I asked is because the machinist/mechanic that I consulted stated that you can take 22 thou off the head & still have 60 thou valve/piston clearance -- this based on doing many of these particular heads/engines & was adamant that it wasn't a guess but a fact. After talking to a Toyota service manager, who told him that 16 thou was waaaaay too much to take off & still be able to use the head my mechanic decided to take the safe route & go with a shim. I told him he didn't have to do that & I was prepared to not use a shim but I have no problem with his decision. No doubt if I would have taken it to a dealer they would have tried to sell me a new head to save their ***. Getting info like this from the factory is like trying to get the keys to Fort Knox! So far so good - just told my daughter to keep a eye on the temp gauge -- I don't want to go through this again.

 

Thanks for posting back with the resolution.

Given the cost of repairs, the shim cost is negligible.