- Safety
- The obvious, use jackstand, I also leave the hydraulic jack on for redundancy.
- Solvants:
- Always use gloves when using solvants: carb cleaner, engine cleaner
etc. Protection is not just for women. When you get older, you hand
will be a mess. Skin dry out over time. When that happens, is easier
to tear and bleed. Just torquing a bolt can cause your skin to rip
from your fingernails. Small bump on edge of metal will cause skin
to rip and bleed as you get old. So protect your skins.
- Working with fasteners
- . Rusted Fastener
- Number 1 rule of thumb: Take your time. Whenever it feels like the
bolt is hard to turn, stop. Take a rest. Impatience is the best way
to strip a bolt. Then you will be wasting more time.
- Use a 6 point socket rather than 12 points or higher. 6 point sockets
has more surface to grip the bolt.
- Put a torque and not a force. Pull with one hand while pushing with
the other to avoid side force on a bolt. One hand on end of wrench,
and other push on wrench at the bolt. That pushing hand is important.
It steady the wrench, and also balance the pushing force on the other
hand. In engineering terms, you are putting pure torque on the bolt
rather than a torque and a shear force.
- Do not use anti seize on threads unless
specified by the manual. Use oil on the thread is ok, but not anti
seize. The anti seize formular makes the bolt too slippery. Since
90% of torque on a bolt goes into fighting friction, if the bolt is
too slippery, you are going to over tighten the bolt and strip the
threads.
- On large part, remove the bolt that is the most difficult to get
to first. Assuming that there are no required sequence. Why? If you
take off easy to get to bolts first, the clamping force will transfer
to the remaining bolts making them even harder to turn.. For a hanging
heavy part, remove the upper bolt last. If you remove the upper bolts
first with only the bottom bolts holding the part up, the overhanging
load will bend or break the flange on the bottom.
- Exhaust bolts
- A ship repairman taught me this trick. They deal with rusty bolts
all the time. Spray graphite lube on the bolt first. Place a combination
wrench on the nut. Not the bolt because nut is easier to turn. The bolt
goes thru the hole that have lots of friction. Use one hand to hold
the combination wrench in place. Use a large hammer, and pound on the
other end of the wrench. The pounding action loosens the rust, and act
like an impact wrench.
- Brake Line Fittings
- Brake line has a hex nut on the end to fasten it to the part. But
the tubing keeps you from putting a socket on the hex nut. Shop teacher
tells you to use a flare wrench to contact the nut as much as possible.
They are still not that good. There is a better way. Use an adjustable
wrench (Cresent wrench). I am not joking. Adjustable wrench is your
best friend if you know how to use it right. First rule, get the biggest
adjustable wrench that can fit. You want the wrench to be stiff and
not spread. Spray graphite lubricant on fitting before loosening. Always
use the strong direction. Now here is the VERY important part. Tighten
the adjustable wrench on the nut as tight as it will go. Wiggle the
wrench with your hand. You will find that the jaws of the wrench still
have some gap on the nut. As you are wiggling it, tighten the wrench
more to take up the remaining gap. Continue to wiggle and tighten until
all gap is taken out of the wrench. This takes about half a minute the
first time you do it. Now you are ready to loosen the nut. In 20 years
of working on cars since highschool, I have never rounded a steel brake
line fitting. I have loosen half rounded rusted steel brake line fitting
this way.
- Cross threaded bolts
- Sometimes after breaking loose a bolt, it will get harder and harder
to turn as you are removing it. If you encounter this situation. Stop,
do not go further. You might have to drill it out, but give it one more
last chance first. Continuing to loosen a bolt that is about to seize
will only make things worst. When the bolt start to get hard to turn,
screw the bolt back into the hole about half a turn unit it is loose
again. Back out the bolt until is tight plus a little more. Continue
with the back and forth action to slowly gain ground in loosening the
bolt. Use penatrant lubricant while doing this. With patience, and plenty
of lubricant, sometimes, the bolt will still come loose.
- Bleeding brakes
- We have always done this before. You bleed the brake, then check the
brake resevoir, add fluid, then bleed the brake some more. Is tedious
back and forth work. There is a better way that works on most cars. Punch
a small hole on the seal of a new can of brake fluid. Quickly turn it
upsidown on the brake resevoir. Now, it acts like the bottle at the office
water cooler. When brake level gets low, the can automatically pour more
in. When you are done, quickly flip the can up again. If the hole is small
enough on the bottle, not much fluid will come out when you are taking
it off the resevoir. Just be careful that brake fluid removes paint.
- Intake / Exhaust Gaskets
- People thinks exhaust leak is no big deal. However, exhaust leaks at
the manifold or down pipe will cause fuel mixture to be wrong. The O2
sensor can be screwed up by air leakage into the manifold between exhaust
pulses. Always check exhaust manifold flange for wrapage when taking it
apart. Use a straigh edge to get a rough idea whether it is wraped. If
you can see daylight, it needs to be ground flat again; otherwise, there
will be gas leakage. A new gasket need to be tightened exactly per sequence,
wait an hour for it to be compressed, then re-tighten again. After the
engine is started and ran, they need to be tightened again. If you can't
tighten it after running the engine, overtighten the nuts by perhaps 10%
so there will still be clamping force after the paper gasket settles.
If a nut is loose on the exhaust manifold, it will wrap. The paper gasket
compresses, and bolts loose torque. Use Permatex HYLOMAR HPF Gasket Dressing
at Pep Boys etc. on the gasket surface. Hylomar will allow the surface
to slide past each other, which is important with aluminum / steel interface.