Head replacement - 3ft-lbs too much?

[pigeon_No_9]

Hello,
Sorry if I'm stretching the boundaries about what belongs in this forum, but I'm in a situation where I would need quick solution.
Changing head for Briggs and Stratton mower - head bolts should be tightened to ~11.8 ft-lbs (16nm). My dynamometric wrench starts at 14,75 ft-lbs (20nm) - do I yolo it and hope for the best?
Is there a real risk of this small difference to strip out the bolts?
Hope someone can help within next few hours.

Cheers

 

[frank_]

there are tables listing bolt strengths, yours are 3/8 whitworth iirc
they are probably far more than 16nm

 

[pigeon_No_9]

there are tables listing bolt strengths, yours are 3/8 whitworth iirc
they are probably far more than 16nm

I am more worried about the engine block rather than bolt heads or threads. no doubt, the bolts will take much more than 16nm to twist the heads off, but the aluminum (I presume?) engine tolerances and leeway is unknown to me.

 

[holeycow]

If you have good feel (which you can develop by using a torque wrench) just tighten the bolts and run the thing. Check them again. Done. Good to go. I wouldn't stress over that.

I'd be worried about the accuracy of the torque wrench at its limits.

you could measure it with a spring-scale and a wrench...

 

[pigeon_No_9]

If you have good feel (which you can develop by using a torque wrench) just tighten the bolts and run the thing. Check them again. Done. Good to go. I wouldn't stress over that.

I'd be worried about the accuracy of the torque wrench at its limits.

you could measure it with a spring-scale and a wrench...

I'll try to apply some common sense to what I feel with the wrench in its lower end. Good point that it could not be as accurate on such low number.
Essentially, was wondering if the 4nm difference is something I should be worried about.
Well, if this fails, I'll be running with a trimmer for some time.

 

[holeycow]

don't be a gorilla. You'll be fine. 12 ftlbs head bolts seems wrong to me...? Idk?

 

[scottr]

Hey holeycow , the small Briggs & Stratton aluminum engines cylinder head torque specification is 140 inch pounds .

 

[arathol]

Hello,
Sorry if I'm stretching the boundaries about what belongs in this forum, but I'm in a situation where I would need quick solution.
Changing head for Briggs and Stratton mower - head bolts should be tightened to ~11.8 ft-lbs (16nm). My dynamometric wrench starts at 14,75 ft-lbs (20nm) - do I yolo it and hope for the best?
Is there a real risk of this small difference to strip out the bolts?
Hope someone can help within next few hours.

Cheers

Get the proper tool for the job. Don't use a torque wrench scaled in ft/lbs. You can get a decent in/lb scaled torque wrench at Harbor freight for $20. If the engine is aluminum, its not hard to strip the threads.

 

[pigeon_No_9]

Get the proper tool for the job. Don't use a torque wrench scaled in ft/lbs. You can get a decent in/lb scaled torque wrench at Harbor freight for $20. If the engine is aluminum, its not hard to strip the threads.

The wrench I have actually is in newton meters. I just tried to convert to ft/lbs to make it easier for whoever was reading this to have some idea and not have to convert the units themselves.