Torquing Bolts with Preapplied Thread Locker

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Honda uses thread locker on the timing belt idler pulley bolt. Oddly they do not use thread locker on the tensioner pulley. Honda considers this bolt non-reusable so I bought a new one which of course came with pre-applied thread locker. The torque is 33 ft-lbs. Considering how difficult it was to remove this bolt, 33ft-lbs seems quite low. Seems like most of the torque will be used overcoming friction from the locker. I almost never question the FSM, but I 33 seems too low. What do you guys think? Thanks.
 
33ft.Lb is plenty in aluminum, I wouldn't go beyond the FSM spec. While it may feel a bit tighter installing with the OE thread locker it being a dry locking compound it doesn't lube the threads like a liquid so it wont put more pressure on the threads than the indicated torque.
Its normal for bolts to come out a harder than they went in.
 
Originally Posted By: Trav
33ft.Lb is plenty in aluminum, I wouldn't go beyond the FSM spec. While it may feel a bit tighter installing with the OE thread locker it being a dry locking compound it doesn't lube the threads like a liquid so it wont put more pressure on the threads than the indicated torque.
Its normal for bolts to come out a harder than they went in.


Thanks Trav. What are doing up so early?
 
Originally Posted By: Trav
33ft.Lb is plenty in aluminum, I wouldn't go beyond the FSM spec. While it may feel a bit tighter installing with the OE thread locker it being a dry locking compound it doesn't lube the threads like a liquid so it wont put more pressure on the threads than the indicated torque.
Its normal for bolts to come out a harder than they went in.


Are you referring to aluminum bolts or aluminum parts? I thought the bolts were aluminum but they are highly magnetic so I assume they are coated steel, maybe high strength too?
 
The bolt is steel but the part it goes into is aluminum correct? Even if it were in iron or steel its still plenty for that size bolt.
I am up doing things, I have always been a bit of an insomniac.
 
Originally Posted By: Trav
The bolt is steel but the part it goes into is aluminum correct? Even if it were in iron or steel its still plenty for that size bolt.
I am up doing things, I have always been a bit of an insomniac.


Yes, I thought bolts were aluminum but must be coating or perhaps anodized. They are strongly magnetic so must be steel especially considering how rusted one was from mount bracket. Mount that attaches to engine is cast aluminum (I think) plus the three mount bolts go through WP through holes into engine.
 
Isn't it always proper policy to use a thread locker/anti seize coating on any bolt that needs a torque wrench so that proper torque can be measured?
 
No not at all, unless otherwise specified torque must be reduced when using never seize. The amount of reduction depends on the type of product used.
Most fasteners are clean dry threads with some exceptions like some high stress engine fasteners that should be oiled.

If the OE supplied fastener has a compound on it or specifies the use of a locking or sealing compound then use spec torque. This is one of the reasons never seize on spark plugs is controversial, if you don't reduce the torque you can pull the threads especially in aluminum heads.
 
Originally Posted By: Trav
No not at all, unless otherwise specified torque must be reduced when using never seize. The amount of reduction depends on the type of product used.
Most fasteners are clean dry threads with some exceptions like some high stress engine fasteners that should be oiled.

If the OE supplied fastener has a compound on it or specifies the use of a locking or sealing compound then use spec torque. This is one of the reasons never seize on spark plugs is controversial, if you don't reduce the torque you can pull the threads especially in aluminum heads.

Torquing on dry threads can result in binding and therefore unreliable results.
 
Originally Posted By: Bamaro
Torquing on dry threads can result in binding and therefore unreliable results.

Only if the threads are dirty. Why would you torque something with dirty threads?

Torquing a fastener installed wet or with anti-sieze (unless specified) without a reduction in torque will result in over-torquing the fastener. Period.
 
Originally Posted By: rooflessVW
Originally Posted By: Bamaro
Torquing on dry threads can result in binding and therefore unreliable results.

Only if the threads are dirty. Why would you torque something with dirty threads?

Torquing a fastener installed wet or with anti-sieze (unless specified) without a reduction in torque will result in over-torquing the fastener. Period.

I'll just finish with this. Ultimately what you are looking for is bolt stretch. Bolts are not properly torqued until properly stretched. If you are confident of the condition of both threads then fine, use nothing on them and you are probably OK. If you are not confident then prepare them properly. This is somewhat of a moot point on things like an oil drain plug where torque is not all that important (I always do by hand) but if you are working on something like rod bolts, accuracy is a must. Thats why a good stretch gauge is a must when engine building
 
Wait a minute your loosing the plot, no one is saying some bolts don't require lube or saying anything about stretch.
Some bolts like head bolts, connecting rod bolts/nuts, main bolts, rocker arm saddles, etc require oil on the threads and under the bolt head, some bolts that enter the cooling system require a sealer and others require never seize or loctite.
Service manuals typically make note this either in a picture or in the description, when nothing is mentioned the default is clean, dry threads.

http://raskcycle.com/techtip/webdoc14.html

A couple of examples from a service manual, notice on the intake install they mention nothing about oiling the thread or any sealers, if you did you would need to reduce the torque to prevent possible thread damage.


 
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