7M-GE head torque

zer_gravity · 01-03-2007, 06:19 PM

hello! first post here, hoping i can get some info from some of the gear heads here

in case you're wondering my name was supposed to be zero_gravity. damn typos!

so i'm going to be a bit of a jerk and deviate from the norm here - i don't own a supra. i've got a '90 7M-GE Cressida. so as i understand it essentially a non turbo mk III supra with a different body.

so here's where i am sitting right now. about 99% sure that i've got BHG or at least the early signs. getting some nice thick white exaust on startup that clears once the engine reaches operating temperature. it does not overheat. i've noticed more recently that after running the reservoir will nearly fill. i don't yet have a lot of oil contamination - nothing on the dipstick but after about 500-700kms some dark brown muddy contamination starts to build up on the oil cap. its not yet that milky consistancy. ive also heard some gurgling from behind the dash, but thats not a common occurance. and the final nail in the coffin - got a compression test. front cylinder is about 180psi. as you go back to #6 it drops down to about 140psi.

i've ordered a head gasket set from toyota and i've got a great mechanic to get the job done. i'd do it myself but i don't have the time and this guy will do it for about $375 (not including parts). so as far as i understand, the stock 58 ft-lbs is too loose which is what is thought to cause BHG's. so what torque should i look at if i'm not doing any mods to the engine at this time? i've read that 70 ft-lbs should do it. any comments?

also, getting some 'might as well while its apart' maintence done. here's my list so far, please feel free to critique it and add.

1. flush radiator

2. check/replace timing belt

3. clean any carburization from cylinder heads/walls using a wire brush - thanks to the online MK3 TSRM.

worthwhile to check vlavle lash and clean valves? anything else i forgot? thanks for any help!

01-03-2007, 06:19 PM	#1
zer_gravity Stock Join Date: Jan 2007 Location: Canada Posts: 5	7M-GE head torque hello! first post here, hoping i can get some info from some of the gear heads here in case you're wondering my name was supposed to be zero_gravity. damn typos! so i'm going to be a bit of a jerk and deviate from the norm here - i don't own a supra. i've got a '90 7M-GE Cressida. so as i understand it essentially a non turbo mk III supra with a different body. so here's where i am sitting right now. about 99% sure that i've got BHG or at least the early signs. getting some nice thick white exaust on startup that clears once the engine reaches operating temperature. it does not overheat. i've noticed more recently that after running the reservoir will nearly fill. i don't yet have a lot of oil contamination - nothing on the dipstick but after about 500-700kms some dark brown muddy contamination starts to build up on the oil cap. its not yet that milky consistancy. ive also heard some gurgling from behind the dash, but thats not a common occurance. and the final nail in the coffin - got a compression test. front cylinder is about 180psi. as you go back to #6 it drops down to about 140psi. i've ordered a head gasket set from toyota and i've got a great mechanic to get the job done. i'd do it myself but i don't have the time and this guy will do it for about $375 (not including parts). so as far as i understand, the stock 58 ft-lbs is too loose which is what is thought to cause BHG's. so what torque should i look at if i'm not doing any mods to the engine at this time? i've read that 70 ft-lbs should do it. any comments? also, getting some 'might as well while its apart' maintence done. here's my list so far, please feel free to critique it and add. 1. flush radiator 2. check/replace timing belt 3. clean any carburization from cylinder heads/walls using a wire brush - thanks to the online MK3 TSRM. worthwhile to check vlavle lash and clean valves? anything else i forgot? thanks for any help!