SEALS, GASKETS & SEALANTSPHS

AUTO

SALS

Installing Sealsand Gaskets

OBJECTIVES Identify common gaskets and seals Properly install common engine gaskets

including cylinder head & valve cover gaskets.

Properly install typical lip seals.

PURPOSE OF A GASKET

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

Gasket Materials– synthetic rubber– cork-rubber– Metal - embossed steel (Corrugated)– paper

GASKET MATERIALS

cork-rubber

synthetic rubber/Neoprene

GASKET MATERIALS

embossed steel (Corrugated)

paper

WHAT CAUSES LEAKS 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

When Replacing gaskets ask yourself , "Why did this gasket fail"

List different things to look for. Did the gasket fail suddenly or over a period

of time? Check the Torque

– is it to Tight– is it to Loose

Gasket Replacement

Check for warp is the valve cover bent or the bolt holes pulled through

Do both surfaces match up 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 Follow instructions. Thoroughly clean & dry the mating surface. Match to the old gasket. Check for proper fit. Is it the right shape, do the

bolt holes all line up. Never reuse gaskets. 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 Note

where sealer is to be applied.

Thanks to Alldata for picture

GASKET INSTALLATION Use alcohol or brake clean on a clean rag

to wipe the oil off of the gasket surface Is the surface dry Tighten in steps Use the torque pattern when tightening Torque to proper specs 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 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.

Many other bolts are to be tighten in steps check the specifications for the car.

CYLINDER HEAD GASKET Must be capable of withstanding tremendous

heat and pressure.

CYLINDER HEAD GASKET Follow gasket makers instructions on whether

or not to use a sealant. Most want you to just clean and dry the surface.

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 Run a tap or thread chaser in bolt holes. Multi-layer steel gasket

CYLINDER HEAD GASKET Always tighten the bolts in the correct

sequence look at the pattern.

CYLINDER HEAD GASKETLook 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

Torque to Yield Bolts

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.

There is a lot more information on the internet. Research it out.

Torque to Yield Bolts Never reuse a torque to yield bolt. They

are beyond their elastic range, past their yield point and will break.

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.

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 TurnEtc.

Torque Angle Gauge

Where do gaskets go?

VALVE COVER GASKETS Check cover flanges for straightness. Use load spreaders when available.

Do not use a sealant. Use high tack or 3M Weather stripping to hold in place.

VALVE COVER GASKETS

Some times referred to as a camshaft cover

VALVE COVER GASKETS

INTAKE MANIFOLD GASKETS

Steel

Paper

EXHAUST GASKETS

Exhaust Rings called Exhaust Doughnuts

fiber facing material on one side and perforated steel on the other.

Fiber surface against the head, Steel on the manifold.

Ring Doughnut

OIL PAN GASKETS

Rear main seal Molded gaskets, oil pan and intake manifold

Rope rear main seal

Rear main seal

VALVE STEM SEALS

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 sealsDeflect the oil

valve

VALVE STEM SEALS Positive Seals attach to the valve guide.

SEALS 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.

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 Seals can be

1. Spring-loaded

2. Springless

3. Single-lip

4. Multi-lip

SEALS

SKF New web site

SEALS

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

SEAL INSTALLATION Install with lip (and garter spring) toward

liquid. Lubricate lip before installation. Use sealant on the outside of steel seals. Use a seal installer.

Check out the power point on seals and seal failures

Speedi-Sleeve shaft repair

Clean and measure the diameter of the worn shaft

Speedi-Sleeve shaft repair

Place the sleeve on the shaft then put on the installation tool

Speedi-Sleeve shaft repair

Hammer or press the sleeve onto the shaft far enough to cover the worn area

USING SEALANTS Use proper sealant for application. Do not use a sealant unless specified in

service manual or by gasket manufacturer. 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 RTV - Room Temperature Vulcanizing Replaces most gaskets forms a rubber seal by absorbing moisture

in the air Sets in about ten minutes Dries in about 2

hours fully cures in 24 hours. Cure times will vary with Temperature,

Humidity, and size of the gap

Aerobic (RTV) - Silicone Sealant 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

Make sure that it is O2 Sensor safe if used around the engine

Do not use around Gasoline Clean and dry surface before using When using around bolt holes go all the

way around the hole.

Thread lockers Anaerobic cures after the

components are put together Locks Bolts & Studs against Vibration

loosening Clean and dry all parts removing dirt, oil,

grease and/or any foreign material

Thread lockers

Four colors Use on screws up to ¼ - Purple # 242 Able to Remove up to 3/4" Bolts - Blue # 271 High Strength Hard to Remove up to 1" Dia. - Red # 290 Wicking Grade for Preassembled Parts - Green

# could be different due to size of bottle

Purple Thread lockers

Low strength Use on screws up to ¼ Applied BEFORE Assembly Carburetors, relay locks,

headlamps, throttle body assembly, choke assembly and fuel injection set screws, body panel mounting fasteners

Blue Thread lockers Medium Strength for all bolts ¼ or

larger Able to Remove with hand tools Prevents parts from loosening from

vibration Protects threads from corrosion Recommend for valve cover

bolts,rocker arm nuts, carburetor studs, motorcycle, jet skis snowmobiles etc.

Applied BEFORE Assembly

Red Thread lockers High Strength Hard to Remove Works well for studs and press

fit Locks against heavy vibration Requires extra effort to remove

or special tools like heat OEM specified as 271 Applied BEFORE

Assembly

Green Thread lockers

Wicking Grade for Pre-assembled Parts

Use on Calibration and adjustment screws

Applied AFTER Assembly OEM specified as 290

There is also a Green High Strength for sleeves

Thread / Pipe Sealant Liquid Teflon Thread Sealant for metal

tapered pipe threads and fittings, replaces teflon tape

Suggested applications 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 Prevents leaks Just wrap tape around

threads on pipes that carry air or liquid

Use on stainless, aluminum, plastic, iron, copper, or brass.

O-Rings O-rings come in several sizes the most

common standard sizes are 1/16, 3/32, 1/8, 3/16, 1/4

O-Rings

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.

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

PHS

AUTO

SALS

Thanks to Federal Mogul for some of the pictures and