Help a dummy use a beam style torque wrench please

[monster1]

I'm torquing down some bolts on the exhaust system on my boat. The torque settings are crucial because if not done properly, the gaskets will leak water into the exhaust system and hydrolock the engine. The spec calls for 25ft lbs on the manifolds and 35 on the exhaust risers. My 1/2" drive click torque wrench won't go this low accurately enough so I have a beam style craftsman I bought. Here's my possible issue. I have all the bolts snug and ready to torque in sequence. I have my hand on the pivot handle exactly where it should be. I slowly turn the wrench tightening the fastener. With each turn the needle slowly climbs then drops as I complete the pass. I reposition the wrench for another pass. The needle goes up to the value (35ft lbs in this case) from the resistance of the fastener. I stop. The tension from the torque wrench unloads and the needle drops several pounds. Does this mean I haven't reached the value (35ft lbs) yet and I keep going until the needle reaches 35 ft lbs with the beam under tension? I'd rather ask than to start snapping off fasteners.

Thanks

 

[Ole Slewfoot]

In an ideal world, you read while the wrench is turning to measure tightening torque rather than breakaway torque.

You will gain something by torquing in stages so the final spec can be hit during the sweep if that makes sense.

 

[wornoutoldman]

In an ideal world, you read while the wrench is turning to measure tightening torque rather than breakaway torque.

You will gain something by torquing in stages so the final spec can be hit during the sweep if that makes sense.

Ole Slewfoot is right on. If the breakaway torque is already at the torque limit release the nut/bolt and torque to spec. The reading takes place as you turn the wrench. Also be sure the handle is not cocked against the bar of the torque wrench as this will alter the reading.

 

[monster1]

Yes. I understand what you are saying. I guess what I'm reading is the breakaway torque rather than the tightening torque. I'll loosen the fastener and try to retorque and get a smoother more accurate reading.

 

[joe49]

Just to add the handle pivots when pulling balance the handle or torque will not be correct.

 

[bczygan]

So pick up a 3/8" HF click type for $10 with coupon!!!!! Get a 1/4" while you're there.

You should have them anyway!

Bill

 

[monster1]

Just to add the handle pivots when pulling balance the handle or torque will not be correct.

Yes. I paid special attention to that. I didn't get a change to work on my repairs today. It was family day. I'll have at it in the morning.

 

[Ole Slewfoot]

So pick up a 3/8" HF click type for $10 with coupon!!!!! Get a 1/4" while you're there.

You should have them anyway!

Bill

IDK, I have a nice new in the case one, back from its ??th warrantee trip, all its good for is a loaner.

 

[monster1]

IDK, I have a nice new in the case one, back from its ??th warrantee trip, all its good for is a loaner.

This is why I bought the beam style.

 

[KMinAF]

I would recommend lubing the bolts or nuts with some anti seize so you get a nice smooth pull on the handle.

 

[Offcenter12]

Do NOT use anti seize on anything that requires a consistent torque. The anti seize will allow you to keep pulling well past the required torque. Clean threads with a few drops of motor oil is the best way to achieve the desired torque.

 

[monster1]

What I ended up doing is chasing all the threads and adding a drop of oil and wiping it away with a rag. It was just enough for the thread to not bind and get a smooth reading. If the needle bounced and then unloaded, I backed the fastener off slightly and then proceeded which left me with a smooth accurate reading. Thanks for all the help.

 

[ngk22r]

Clean threads with a few drops of motor oil is the best way to achieve the desired torque.

Only if it calls for oil on the threads, certain times there is to be no oil at all.

 

[Ole Slewfoot]

I find most of the time on engine fasteners, you oil unless it says 'install dry'.

 

[Wamsutta]

I find most of the time on engine fasteners, you oil unless it says 'install dry'.

Ding Ding! We have a winner!

 

[jonesg]

He needs a new boat.

 

[WWheeler]

The best advice has already been given. I'd add that if the torque specs are that critical and it's all not brand new it sure wouldn't hurt to clean the threads up with a wire brush &/or thread restorer first.

 

[franzdom]

The torque specs are wrong if they are in units of ft-lbs.