- Joined
- Aug 9, 2022
- Messages
- 144
The FSM procedure for installing the cam caps states "4. Install the camshaft bearing caps and tighten the bolts finger tight 5. Using the tightening sequence shown, tighten the bearing cap bolts to 10N·m (89 in. lbs.)". There is no mention of whether this torque value should be applied when the bolts are clean and dry, or whether they should be lubricated with oil or something else. For a given torque value, the effect of lubrication can mean an increase in clamp force by up to 40%, so it's a bit concerning that there is no clarification on how the bolts should be prepped prior to installation.
I looked in a few other sections of the manual and could not find any bolts that explicitly said were to be oiled before installation, however, I did find a few installations where they explicitly specified thread locker, grease, or lock and seal adhesive. I have read that in general it's common to lightly oil engine internal bolts prior to installation, but the sections about installing head bolts and rod caps have an explicit note saying not to apply any lubricant to the fasteners.
I purchased a couple new cam cap bolts which were not oiled, so I assume they would also be this way on a brand new cylinder head. Cleaning and prepping a cylinder head in a parts washer would result in removing any residual oil in the threads, so oiling the threads would need to be a separate step at reassembly. Is it safe to assume that the cam caps should be installed clean and dry when torquing to 89 inch-lbs, or should it be assumed that they should be torqued to that value with oil on the threads?
I looked in a few other sections of the manual and could not find any bolts that explicitly said were to be oiled before installation, however, I did find a few installations where they explicitly specified thread locker, grease, or lock and seal adhesive. I have read that in general it's common to lightly oil engine internal bolts prior to installation, but the sections about installing head bolts and rod caps have an explicit note saying not to apply any lubricant to the fasteners.
I purchased a couple new cam cap bolts which were not oiled, so I assume they would also be this way on a brand new cylinder head. Cleaning and prepping a cylinder head in a parts washer would result in removing any residual oil in the threads, so oiling the threads would need to be a separate step at reassembly. Is it safe to assume that the cam caps should be installed clean and dry when torquing to 89 inch-lbs, or should it be assumed that they should be torqued to that value with oil on the threads?
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