3b head torque

[mallred]

It has been a long day, but I have the head on my 81 bj42 and have torqued the head to 87 foot pounds,, now if I am reading the FSM correctly I am to torque to 92-102 foot pounds after the engine has warmed up ? or is it after it cools down after the valves are readjusted?

Myrle

 

[MadmanCruiser]

It has been a long day, but I have the head on my 81 bj42 and have torqued the head to 87 foot pounds,, now if I am reading the FSM correctly I am to torque to 92-102 foot pounds after the engine has warmed up ? or is it after it cools down after the valves are readjusted?

Myrle

I'd be interested to hear the answer to this....anyone?

Adam

 

[crushers]

torque it to 100 ft lbs when you are assembling and you are done.
i have been to many engine rebuilders over the years and no one takes the rocker shaft back off to retorque.

cheers

 

[mallred]

I torqued to 87 FT pounds ran the engine to temp , shut it down and retorqued to 100 FT pounds after readjusting the valves and engine was luke warm. I was really suprised on how much it took to get the extra 13 FT pounds, the second torquing was really needed.

 

[crushers]

couple questions:
you did put oil on the threads and under the bolt heads?
you do realise the tolerances and friction on the threads are tighter when the engine is warm?
that it takes an extremely accurate torque wrench to go from 87 to 100 ft lbs? that it is very easy to over tighten the head bolts which can lead to stretching and breaking of the bolts?

finally, i am sitting here reading the factory manual for the installation of the head:
Install Cylinder Head
a) place a new gasket on cylinder block
CAUTION: be careful of the installation direction
b) Place cylinder head on the cylinder head gasket
c) apply a light coat of engine oil on the threads and under the cylinder head bolts
d) install and uniformly tighten the eighteen cylinder head bolts in several passes in the sequence shown
TORQUE: 1200 kg-cm (87ft-lbs 118N-m)

WHERE DOES IT SAY TO RETIGHTEN TO 102ft/lbs after the engine is warmed up? which leads me to ask, where did you read this?

cheers

 

[colby1979]

Thats what I was wondering Wayne, my FSM says nothing about this???

 

[crushers]

please realise i am not trying to be an ass here, i have assembled dozens of these 3Bs and if i am doing it wrong i want to know...
cheers

 

[exmodlad]

the factory has probably done hundreds of thousands of these engines.....why second guess the maker....my manual say 87 Lbs and thats it.......it works for me.....and that is how i see it

Gord

 

[PacToy]

My Toyota Engine repair manual for B, 3B, 11B, 13B, 13B-T also says it should be 87 ft-lbs.

It Actually says this:
Install and uniformly tighten the eighteen cyclinder bolts in several passes, in the sequence shown.

Torque 1,200 kg-cm (87 ft-lb, 118 N-m)

 

[mallred]

couple questions:
you did put oil on the threads and under the bolt heads?
you do realise the tolerances and friction on the threads are tighter when the engine is warm?
that it takes an extremely accurate torque wrench to go from 87 to 100 ft lbs? that it is very easy to over tighten the head bolts which can lead to stretching and breaking of the bolts?

finally, i am sitting here reading the factory manual for the installation of the head:
Install Cylinder Head
a) place a new gasket on cylinder block
CAUTION: be careful of the installation direction
b) Place cylinder head on the cylinder head gasket
c) apply a light coat of engine oil on the threads and under the cylinder head bolts
d) install and uniformly tighten the eighteen cylinder head bolts in several passes in the sequence shown
TORQUE: 1200 kg-cm (87ft-lbs 118N-m)

My mistake, I was using Max Ellery's manual, It gives you cold Valve Settings and kicks you back tothe fornt of the book for tuneup specs. I had earmarked the H engine by mistake and it does give you warm numbers for the head bolts of 92 to 102 ft #s.

I did not have my Adobe when I was doing the work on the engine and have my FSM on a pfd file. It now works and mine is the same as yours as far as your quote. The engien has not been ran since I adjsuted the valves and I guess I will check the torque before I run it and see were I stand. My guess i that it will be ok since the warm engine should have expanded metal and what I am thinking is that would be a lower torque rather than a over torqued head.
I will be interested in what the #s are now.

Myrle



WHERE DOES IT SAY TO RETIGHTEN TO 102ft/lbs after the engine is warmed up? which leads me to ask, where did you read this?

cheers

Myrle