Head Bolts

[AndyW]

I'm replacing some valves and rebuilding my Rover T-series DOHC engine. Some questions for you experienced people...

 

- the head bolts require 3 stage torquing. Do I fit the bolts dry, or lightly oil them, or use some anti-seize on the threads (CopperEase) ?

 

- other bolts to fit the camshaft carriers need thread lock. How much loctite do I put on and where does it go - a complete circle or just a dab? And do these bolts go in dry, or do I oil them as well as using loctite?

 

Sorry for the basic questions, but as I've 've never done this before I thought it best to ask. Thanks.

 

[steve in stockport]

Your new head bolts should come with a sheet of fitting instructions specific to the engine they are going into. On my vauxhall with a four stage fitting I had to lightly oil the thread and oil under the bolt head but not under the washer. If you have to oil the threads avoid putting too much oil on and make sure the bolt holes are clean or you could get hydraulic compression and crack the block.

When using thread lock don't oil the threads, if the locking compound is a liquid apply a couple of drops and allow to run round the thread and if it's a gel/paste apply a layer to just fill the thread all the way around, it doesn't need to be like icing a cake.

[AndyW]

Thanks Steve. I'm re-using the existing head bolts as per Haynes and Rover overhaul manuals. They are flange bolts with no separate washers. I've just spotted in the Rover overhaul manual it says to tap holes to clean, then lightly oil the thread and under the bolt head. Thanks for the agreement. And for loctite info - all makes sense now.

[tractor]

if you put oil on the bolt don't bother putting thread lock on it wont be doing much mixed with oil

[AndyW]

Got that. They're different bolts. Head bolts + oil. Camshaft carrier bolts + thread lock / no oil.

[Guest mcramsay]

Applying oil to the threads should only be done so if specified by the manual as the torque specifications for bolts will change depending if lubricated or not.