rich123

Timing belt broke and I crashed the heads. Mechanic shop disassembled and machine shop rebuilt heads. Mechanic shop reassembled. After assembly loud valve/tappet noise. Mechanic shop stated that valve adjustment was the responsibility of machine shop, not him. Is this true? Is the problem the machine shop?

thanks so much....
Richard

5sp_jzz30

iTrader: (2)

valve adjustment is done after the heads are torqued down on the block. you can do a valve shimming job with the head off but it will not be perfect, and considering you are playing with clearances of 0.008-0.010" inch, a 0.001" inch can have an impact. shimming being off by 0.001" inch wont make noise but if it off by 0.003" inch then it definitely will and eventually it will damage the lifter, shim, and camshaft itself.

time to find a better mechanic.

since you say heads, as in plural, is it safe to assume you have a sc400 with a v8 in it.

please provide more information about your engine. what do you mean you crashed the heads? you bent the valves? usually when you bend valves you dont damage seats, thus negating the need for an actual motor/head rebuild.

i do plenty of engines and head all the time where the timing belt breaks and valves are bent. i always check the seats for runout with a gauge. i had only a handful of motors actually damage the seats in the process of bending valves, thus requiring the seats to be recut.

i have a feeling the mechanic is pulling your leg.

rich123

yes, it is a SC400 and after overheating the timing belt broke and some valves were bent.

xspsi6

iTrader: (31)

Sounds like you got a crap mechanic. Sorry to hear this but it happens more than it should.

rich123

Thank you very much for your time and expertise....
Richard

bugjug

what year sc400? vvti?