Presentation on theme: "SEALS, GASKETS & SEALANTS PHSAUTOSALSPHSAUTOSALS Installing Seals and Gaskets."— Presentation transcript:
SEALS, GASKETS & SEALANTS PHSAUTOSALSPHSAUTOSALS Installing Seals and Gaskets
OBJECTIVES n Identify common gaskets and seals n Properly install common engine gaskets including cylinder head & valve cover gaskets. n Properly install typical lip seals.
PURPOSE OF A GASKET n Purpose of a Gasket –To confine; gas, oil, water, vacuum or exhaust –Seal out foreign objects such as; Dirt, Water –Must withstand heat, cold, pressure, erosion, corrosion, moisture and oil
GASKET MATERIALS embossed steel (Corrugated) paper
WHAT CAUSES LEAKS n Causes of leakage, –Worn or damaged seals –Worn or damaged gaskets –Worn or bent parts or shafts –Fasteners over tighten or to loose –wrong parts or gaskets –nicks or burrs –Improper installation
n When Replacing gaskets ask yourself, "Why did this gasket fail" n List different things to look for. n Did the gasket fail suddenly or over a period of time? n Check the Torque –is it to Tight –is it to Loose Gasket Replacement
n Check for warp is the valve cover bent or the bolt holes pulled through n Do both surfaces match up n Examine the gasket very close, are the holes in the same spot Gasket Replacement
If you just replace the gasket it may go out again. Also some Bolts need to be checked for torque for example some head gaskets need to be retorqued. When installing gaskets check the manufactures instructions for the proper procedures. Gasket Replacement
GASKET INSTALLATION n Follow instructions. n Thoroughly clean & dry the mating surface. n Match to the old gasket. n Check for proper fit. Is it the right shape, do the bolt holes all line up. n Never reuse gaskets. n Ask yourself, Do you need Sealer. Use high tack or 3M Weather stripping to hold in place. Only use Silicone on mating lines and where two gasket are joined together, like on valve covers.
GASKET INSTALLATION n Note where sealer is to be applied. n Thanks to Alldata for picture
GASKET INSTALLATION n Use alcohol or brake clean on a clean rag to wipe the oil off of the gasket surface n Is the surface dry n Tighten in steps n Use the torque pattern when tightening n Torque to proper specs n Use a quality gasket, saving a buck or two on a cheap gasket or trying to reuse a gasket is not worth it.
CYLINDER HEAD GASKET n When tightening a cylinder head gasket that is not torque to Yield it is best to tighten in steps. How much should you go, my rule of thumb has been if under 60 lbs. Tighten in 2 steps. If over 60 lbs. tighten in three steps. For example if it is to be tighten to 100 foot lbs. Tighten in this sequence 35 – 70 – 100. n Many other bolts are to be tighten in steps check the specifications for the car.
CYLINDER HEAD GASKET n Must be capable of withstanding tremendous heat and pressure.
CYLINDER HEAD GASKET n Follow gasket makers instructions on whether or not to use a sealant. Most want you to just clean and dry the surface. n What type of sealant and how much? Most head gaskets do not want any sealant. If you have an aluminum head and a cast iron block (sometimes referred to as a bi-metal engine) it will expand at different rates, if you use a sealant you are going to have a leak. Most manufactures will use a graphite gasket to allow for motion during the expansion.
CYLINDER HEAD GASKET n Run a tap or thread chaser in bolt holes. n Multi-layer steel gasket
CYLINDER HEAD GASKET n Always tighten the bolts in the correct sequence look at the pattern.
CYLINDER HEAD GASKET Look at the pattern, starts in the center and rotates out.
USING STRAIGHTEDGE Check in several directions what is the specifications? How much can be taken off?
Torque to yield (TTY) bolts are used in many engines today, the bolts need to be replaced. When installing them you need to have them clean and oiled then tighten to manufacture’s preload setting. Then tightened them in a series of stages usually about 90 degree’s at a time. Torque to Yield Bolts
n Bolts stretch, they are elastic most of the time they will return to their original shape. But on Cylinder heads to keep the right tension on the head they stretch almost to the breaking point. If you try to reuse them they will break. n There is a lot more information on the internet. Research it out.
Torque to Yield Bolts n Never reuse a torque to yield bolt. They are beyond their elastic range, past their yield point and will break. n A example would be for a Torque to yield (TTY) bolt when installing them you would torque them down to 35 foot pounds then tighten an additional 70 degrees. n Every car is different check the manual.
Degree wheel If your not familiar with a degree wheel, Learn it. 90 is ¼ Turn 180 is ½ Turn Etc.
VALVE STEM SEALS n Deflector seals usually called umbrella seals that move with the valve and Positive Seals attach to the valve boss and GM O-rings
VALVE STEM SEALS umbrella seals Deflect the oil valve
VALVE STEM SEALS n Positive Seals attach to the valve guide.
SEALS n We have come along way from the old felt & leather seal. Most seals today are made of Nitrile. Some Seals are made of Viton, Silicone, or Polyacrylics. For more information on what seals are made of go to the CR website to find out. n The first job of the seal is to keep the oil in and the dirt out but it can also be used to separate fluids and to with stand different pressures. Proper installation and inspection is very important
SEALS n Seals can be 1. Spring-loaded 2. Springless 3. Single-lip 4. Multi-lip
SEALS n A. The flexible material component of the seal which produces the lip. In this design there is only one lip, the primary sealing lip. B. The outer shell of the seal holds the seal in place. C. The garter spring (found in most seal designs) is a coiled wire spring that provides a controlled radial load over time.
Inspect the shaft that the seal rides on it might be bent or damaged. You may have to install a sleeve or clean up with crocus cloth or replace with a new part SEAL INSTALLATION
n Install with lip (and garter spring) toward liquid. n Lubricate lip before installation. n Use sealant on the outside of steel seals. n Use a seal installer.
Check out the power point on seals and seal failures
Speedi-Sleeve shaft repair n Clean and measure the diameter of the worn shaft
Speedi-Sleeve shaft repair n Place the sleeve on the shaft then put on the installation tool
Speedi-Sleeve shaft repair n Hammer or press the sleeve onto the shaft far enough to cover the worn area
USING SEALANTS n Use proper sealant for application. n Do not use a sealant unless specified in service manual or by gasket manufacturer. n Types of sealants –Hard drying like 3M Weather stripping or a glue to keep a gasket in place –Aerobic (RTV)cures when exposed to air –Anaerobic cure after the components are put together (Thread lockers)
Aerobic (RTV) - Silicone Sealant n RTV - Room Temperature Vulcanizing n Replaces most gaskets n forms a rubber seal by absorbing moisture in the air n Sets in about ten minutes Dries in about 2 hours fully cures in 24 hours. n Cure times will vary with Temperature, Humidity, and size of the gap
Aerobic (RTV) - Silicone Sealant n Blue is the most common color but also comes in Black, gray, bronze,clear, red and white(white is for the bathroom)
Aerobic (RTV) - Silicone Sealant n Make sure that it is O2 Sensor safe if used around the engine n Do not use around Gasoline n Clean and dry surface before using n When using around bolt holes go all the way around the hole.
Thread lockers Anaerobic cures after the components are put together n Locks Bolts & Studs against Vibration loosening n Clean and dry all parts removing dirt, oil, grease and/or any foreign material
Thread lockers n Four colors n Use on screws up to ¼ - Purple n # 242 Able to Remove up to 3/4" Bolts - Blue n # 271 High Strength Hard to Remove up to 1" Dia. - Red n # 290 Wicking Grade for Preassembled Parts - Green n # could be different due to size of bottle
Purple Thread lockers n Low strength n Use on screws up to ¼ n Applied BEFORE Assembly n Carburetors, relay locks, headlamps, throttle body assembly, choke assembly and fuel injection set screws, body panel mounting fasteners
Blue Thread lockers n Medium Strength for all bolts ¼ or larger n Able to Remove with hand tools n Prevents parts from loosening from vibration n Protects threads from corrosion n Recommend for valve cover bolts,rocker arm nuts, carburetor studs, motorcycle, jet skis snowmobiles etc. n Applied BEFORE Assembly
Red Thread lockers n High Strength Hard to Remove n Works well for studs and press fit n Locks against heavy vibration n Requires extra effort to remove or special tools like heat n OEM specified as 271 n Applied BEFORE Assembly
Green Thread lockers n Wicking Grade for Pre-assembled Parts n Use on Calibration and adjustment screws n Applied AFTER Assembly n OEM specified as 290 n There is also a Green High Strength for sleeves
Thread / Pipe Sealant n Liquid Teflon n Thread Sealant for metal tapered pipe threads and fittings, replaces teflon tape n Suggested applications n Stainless steel fittings, head bolts into through holes (water Jacket), oil PSI sending units/sensors, oil and coolant lines, intake manifold switches, rear axle fill plug, fuel fittings
Teflon Tape n Prevents leaks Just wrap tape around threads on pipes that carry air or liquid n Use on stainless, aluminum, plastic, iron, copper, or brass.
O-Rings n O-rings come in several sizes the most common standard sizes are 1/16, 3/32, 1/8, 3/16, 1/4
O-Rings n O-Rings come in several shapes an O being the most common but you can find others in D shape, Square-ring and a modified X. n O-Rings also come in different types of materials make sure what you are using is compatible with the fluid it is next to.
The End For this little leak PHSAUTOSALSPHSAUTOSALS Thanks to Federal Mogul for some of the pictures andFederal Mogul