No compression

[DewCatTea-Bob]

By: BevelBob...
" but a usefull check on the wrench is to use a fish wieghing scale and attach to a breaker bar and socket at exactly 12 inches and tighten up say an axle nut to 28 foot pounds,then check against the wrench."

____ How do ya know that the fish-scale is calibrated ? _ Catch a 28 foot-pound fish? -lol
__ I've already told Jim to take advantage of the fact that he has two different t.wrenches.
But to check one's calibration, why not just compare your-own with someone-else's newer t.wrench !?


Easy-Cheers,
-Bob

[Bevel bob]

I don't know anyone else who has a T wrench, or the know how to use one !! ,appart from me, sadly we have become a nation of wimps that pay someone else.I do have access to several motor repair shops but having seen how they work and care for the tools ,no thanks. My son is a serious fisherman and his stuff is accurate to an ounce ,with a wrench 5 lbs error is likely anyway so no contest. The only time i strip threads is when trusting a manual and a T wrench so now I just use feel, and 50 years experience with old threads.

[Rick]

I don't like to pass off something 'I read somewhere' as fact, but, I did read an informal test someone did, and the result was that without a torque wrench most people over tightened bolts- it got worse as the bolts got smaller.
I think one of the best reasons to use a torque wrench is to apply an even pressure- especially important in something like a cast aluminum head, where 'feel' could result in uneven force holding parts together, and could cause trouble.
Rick

[Bevel bob]

To use a T wrench means you normally look up the setting in a manual, if you used the figures in many manuals you could do real damage, some manuals have bad errors,not a problem for me as i have been finding leethal errors in manuals for years and now apply my own common sense .I have a selection of T wrenches and they are used, but i don't blindly follow anyones instructions , Its been too costly in the past.

[Rick]

Lots of factors involved in determining the right torque value, and small things can make a big difference, this page explains some of them:
http://www.mechanicsupport.com/articleTorqueWrench.html
So BevelBob is right, if a published value starts to feel wrong, you should stop. There's nothing wrong with using feel as a gage, but after getting 1 head bolt tightened to what feels good, I'd put a torque wrench on it to read the value and tighten the rest to that value, so the tension in all of the bolts is equal.
Rick

[Rick]

Ok, before someone else points out the error in my terms, a torque wrench doesn't measure tension in the bolt- just the amount of torque being applied to it, which is why some guys get involved in measuring bolt stretch, etc.
It's usually hard to measure tension in a bolt, so a torque wrench is better than nothing, but will not, as I stated, guarantee equal tension in the bolts.
And, does anyone know why Ducati chose to use 4 big bolts instead of studs?
Rick

[Bevel bob]

Studs would make it impossible to remove the barrel without sawing through the frame, so it seems a sillly question, however having worked on most vehicles over the years i have been amazed at the daft designs perpitrated by major manufacturers who have been building cars for 100 years .

[Jordan]

And, does anyone know why Ducati chose to use 4 big bolts instead of studs?
Rick

So head & cylinder removal could be done in about 15 minutes?

Jordan