Hi guys, can any one advise me on which 1/2 inch Torque wrench ( 10NM-150NM ) to buy. Any brands or company links. Also do I need to use a torque wrench to tighten the manifold bolts and valve cover. I can’t remember whether the valve cover has nuts or bolts.
kind regards,
saj

 

Just about any quality make of torque wrench will do. My personal preference is a 1/4 inch or 3/8 inch drive. I like to keep the torque in the middle range of the tool. You should go to the "How to Section" and download the tech manual for the x-type. There is a torque value and a torque sequence. When removing the intake manifold make sure the vehicle has sat overnight. Warn engine will cause pull out of the fastener inserts.

 

Thanks Avern for yiur kind advice. Your a gentleman.
Kind regards,
Saj

 

I've been happy with the TEKTON brand "clicker" type for most nuts and bolts. I have one each in 1/2, 3/8 and 1/4 drive that I bought on Amazon only a couple of years ago. Typically there is some overlap on the torque ranges between the drive sizes, but I find that 1) using adapters to fit a smaller socket on larger wrench sometimes makes it kind of clumsy to use, 2) often doesn't fit in the available space and 3) sometimes it can be hard to feel that click when the wrench is really too big for the job, especially with gloves on if its greasy or still hot parts. So I have all three sizes.

Also I have a couple of older beam style torque wrenches, Craftsman brand, but I rarely use those anymore except for certain applications that require more finesse. The downside is often the orientation of the tool in service is such that you can't directly see the face of the scale. For years, I would often put a piece of electrical tape on the face of the scale (or even the back of it) so I could more easily tell when the correct torque was reached. That's the nice thing about the clicker type, you dial it in first and then you can "feel" the tool click when the proper torque is reached. There's electronic ones too that audibly beep when the torque setting is reached but those are usually for high-precision work and probably overkill for most auto repair work. My luck, the batteries would probably leak and ruin it.

I am often quite obsessive-compulsive about setting the proper torque, especially when it involves sealing surfaces and gaskets because uneven torque can deform the parts and cause leaks. As a general rule, if the book shows a torque sequence diagram, then its critical. I can't speak to what exactly your X-type has on the valve cover, but most valve covers usually require far less torque than would be optimum for a 1/2 inch drive. Check the repair manual and follow Vern's advice above about buying a tool in the appropriate torque range for the application. You can even buy a set of all three drive sizes and cover just about every size nut and bolt in your car, but be sure to consider the length of the handle particularly for the 1/2 inch drive (longer requires less effort, but doesn't fit everywhere) and different ratcheting types are either fine $$$$ or coarse $$ and larger heads sometimes don't fit in tight places. There's been many times I wished I had a finer ratcheting mechanism or a smaller head, but can't justify the prices for those for no more shade-tree wrenching than I do.

 

Sb10, being someone that has received more training about torque than I care to admit to (mainly because my life depended on things being constructed very critically, gotta love living on a submarine). For most applications in a car, you can get away with a "clicker type" torque wrench. Like was mentioned, you need to be good about slowly applying more and more force until it clicks and then immediately stopping. My personal preference is for the dial style where I can see the actual torque that I applied. But, I am a little **** about things that I torque (can't imagine why). Never used a digital torque wrench, so, I would toss them into the range of the "clicker style" torque wrenches.

For you, odds are, you are only going to need a 3/8" drive torque wrench that will go say 0-100 ft-lbs. Worst case, get one that goes up to 150 ft-lbs. Anything beyond that is just overkill for what is used on modern day cars. If you need something higher than 100 (or 150 ft-lbs), your local auto parts store will rent you one for essentially free. Odds are, you will need a special socket anyways (only torque I know of on the X-Type that goes above 150 ft-lbs is the front spindle nut which is like 175 ft-lbs. The basis for getting a lower range torque wrench is 2 fold. The first being price. The higher the torque, the bigger the wrench, the more it is going to cost you. Yes, I personally own a 0-250 ft-lbs torque wrench, but this would have cost me around $400 to buy, but it was given to me (dial torque with a light indicator for when you reach your desired torque). The second being that the larger scale is going to be hard to read to a small value. Depending on the stance you have with torque wrenches, some may be restricted to as little as 50-90% of full scale (ie, a 0-100 ft-lbs torque wrench would only be able to be used for torques between 50 and 90 ft-lbs and be considered accurate). There is some truth to this requirement. But, for most car applications, this limitation (ie, the 50-90% limitation) is overkill. The big thing is making sure that the torque wrench goes to the same value every time.

With all this being said, 2 things to keep in mind with the clicker type wrenches. First, you need to exercise them a few times before using them for a good torque. This moves around the lube a little and just breaks the rust free inside the wrench which can affect the torque. All you do is simply dial the wrench to the torque you want, find some bolt that you can torque to whatever (or that has a higher torque than you are going to) and apply enough torque to make it click 4-5 times. Every time you dial a new torque, repeat. The second is how you store the torque wrench between uses. This is where I am going to default to the owner's manual on where it should be left as there are 2 general ideas out there. The first being that the snap torque wrench should be dialed to minimum (lowest value, not all torque wrenches go to 0). This minimizes any continual load on the beam which over time can loose its strength and become erroneous. Some are built such that they need that continual stress on the bar and need to be set to a specific value to keep them as accurate as possible.

With accuracy being mentioned, if you are **** like me and want to calibrate your own torque wrench, you have 2 options. You can send the torque wrench out and there are shops there that will put it on a special device and tell you how far off it is at various torques (this is normally cost prohibitive and only really used by places that have a need for documenting precise torques - like the nuclear power plant that I work at, another would be the aircraft industry). The other way is to simply take any socket that fits the end of your torque wrench and weld a bar on to the socket that is about 14" long. What you are going to do is measure 12 inches down from the center of the socket and drill say a 1/8" hole (big enough to put an S-hook through, but keep the center of the hole at 12 inches). From there, you can put the torque wrench at the edge of a table with the bar handing off the side, run a string down to a bunch of weights (lifting weights will be accurate enough for this) and then keeping the car level with the ground, set the clicker style torque wrench to the weight on the ground and then pull on the torque wrench. If you can lift the weights off of the ground, then your torque wrench is a little low (slowly adjust up on the torque wrench until it clicks just as the weights come off of the ground). If you can lift the weights off of the ground, then dial it down slightly and try again. Repeat until the wrench clicks as the weights just come off of the ground. If you are lucky, you may know of a place that has calibrated pads that you can put a torque wrench on and compare actual verses set torques. These are nice as you can get real time values as you are using the torque wrenches. You can repeat this by simply using something like a fish scale, but you have to find something to anchor it to. Then it is just a matter of keeping the scale perpendicular to the welded bar.

As you can see, I am a little **** with torque. But, like I mentioned, my life depended on these torque being good. Too little, the water pressure could push stuff apart and let water in. Too high, the bolts can catastrophically fail and well, that just makes for a bad day (aka, sub on the bottom of the ocean). So, if you have questions about torque, let me know. The big errors that people make is not following directions. When I say this, what I mean is that some torques are based on putting the bolt in dry (ie NO LUBE!!!!). Others are meant to have lube and be torqued. Putting in a bolt that should be dry, but has lube applied can over torque the bolt. An example of this on the car that can be disastrous is say on the head bolts. Those are torqued really close to their breaking point. You over stress those, imagine what would happen when you start up your car and your head comes flying out of the engine bay. Obviously putting a bolt in dry that should have been lubed can result in under torquing and can result in leaks. Not a big deal other than making a mess. Most torqued joints just need all bolts torqued to exactly the same value. Valve covers are a prime example of this. They don't even need to be torqued to the correct value, but if you torque one to the high end of the allowable and the one right next to it to the low end of the allowable, I can almost guarantee you will have a leak. In short, the valve cover will flex under this condition and not squeeze the parts together like they need to be.

 

"I am **** about torque". To me that screams that it needs to be on a t-shirt.

 

Alfa, who says I don't have a shirt with that on it. Besides, everyone says my car makes this much horsepower, oh yeah, mine makes this. Horsepower is just a measure of force at a constant speed. Torque is what makes you accelerate. That is the number that I like to see. Give me a car with lots of low end torque and I will show you a fun car to drive around town.

 

My nephew works at just such a place that tests and calibrates all sorts of instrumentation including torque wrenches. I was really surprised to learn that they regularly test and certify Pittsburgh torque wrenches from Harbor Freight. He said some of their clients found that they were almost always within their specified tolerance and with such a small percentage of units being out of spec, it was cheaper and faster to just replace it with another $20 HF unit than to pay them the labor to re-calibrate most of the more expensive brands. I never would have guessed.

 

"Horse Power sells Cars. Torque wins Races!"

Carroll Shelby

 

With Top Fuel. Among the fastest-accelerating machines in the world, 11,000-horsepower Top Fuel dragsters have at least 7,400 foot-pounds of torque. Over 10,000HP, apparently there is no dyno available to measure torque.

That being said, there are racers with less than 11,000 (by hundreds of horsepower) who win races because of deliverable torque against higher horse power cars. And because these cars have progressed to these levels, remember they now only race to 1,000 feet instead of the old quarter mile length due to safety concerns.

I'd never argue with Shelby!!

Here's an interesting tid bit. Ever wonder why the exhaust points skyward?

open exhaust headers are angled upward, and they push enough gas to give the car an extra 1,100 pounds worth of downforce to help with the almost-impossible task of sticking its giant rear tires to the drag strip.

 

Dell, there are a lot of interesting facts about the top fuel cars like it takes over 400 hp just to turn the supercharger on those cars, the engine only runs for about 9000 revolutions before needing to be overhauled, and the engine is more efficient (and also generates more power) than an engine on a Boeing 747.

Wiht top fuel cars, they only have a single gear (essentially direct drive) and they can develop the extreme torque through slipping the clutch (acts like a torque converter).

 

Ha! Wouldn't surprise me a bit.

I'm with you about the low end torque and the feeling when you push down on the accelerator. Nothing else like it.