Is it always best/recommended to use a torque wrench to tighten spark plugs correctly or do most people not bother?

Cheers
Richard.

 

Ive never torqued a spark plug up in my life. It doesnt need to be overly tight, just tighten by hand, and then 60' with the ratchet.

 

A good quality torque wrench should always be used on every fastener where possible. Impreza spark plugs are torqued to 21Nm or 15.2lbft

 

Thanks guys.

I'm pretty new to the diy work on the car front, and don't really have much past reference for how tight things should be or feel - so probably best getting a torque wrench.

This one looks decent enough: http://www.amazon.co.uk/gp/product/B...f=ord_cart_shr

 

I think you will have trouble using a torque wrench to do the plugs due to the lack of space. Depending on the size of it of course.

 

It's for my Mk5 Golf GTI and I'll need to use an extension rod/pole on them.

 

If you dont fit alot of fastners regularly then 100% use a torque wrench!

 

Sounds like good advice

 

If you are not used to working out how much force to apply, then its always good to use a torque wrench to get an idea of how much effort equates to how much torque. Bearing in mind the length of the wrench dictates the amount of leverage (the longer the wrench, the less effort you need to get the same torque).

I do it by feel which is hand tight (or if its a new spark plug; tightent until resistance is felt, where the crush washer is flattened) then upto 1/8 of an extra turn.

These are alloy cylinder heads, so threads strip easily and plugs don't need to be super tight, so basically its hand tight and nip them up a touch. If unsure, tighten with your hand torwards the base of the wrench to reduce the leverage.


Notes with torque wreches: When not in use, wind back the spring to zero lb/ft. To stop the internal spring from stretching which will keep it accurate. Large torque wrenches are not very accurate for low torque settings, as found on sparK plugs (some don't even adjust that low). Get one with easy to read/understand scales, as some can be confusing (My uncle's mini Blue-point wrench reads in 7ths ).

 

Thanks Ali - very useful and good tip on the torque wrench spring.