The document discusses valve and seat service for engines. It covers valve types and materials, testing valve springs, and refacing or replacing valve seats. Key steps include checking valve springs for squareness and force, diagnosing issues like carbon deposits, and addressing high-velocity seating.
Propeller shaft is a circular shaft which is used to transmit the power or rotational motion from the gear box to the final drive.
The propeller shaft as the name suggest “ propels the vehicle.
Air Suspension System is commonly use in BMW,Mercedes,Audi types luxurious types Cars for protect from damaging, increasing life of the vehicle ,increases the handling , increases comfort of passengers and many more..
So according to me if you remove the suspension system, then you feel like in bull-cart in Audi, Mercedes, BMW type luxurious cars . The only diffrence is speed.
So the scope of Suspension System is Too Bright !!!
UNIT-1-VEHICLE STRUCTURE AND ENGINES.pptShanmathyAR2
VEHICLE STRUCTURE AND ENGINES
Types of automobiles, vehicle construction and different layouts, chassis, frame and body, resistances to vehicle aerodynamics (various resistances and moments involved), IC engines-components functions and materials, variable valve timing (VVT).
FLYWHEEL AND GOVERNORS
A flywheel is a mechanical device specifically designed to efficiently store rotational energy.
IT STORES ENERGY DURING POWER STROKE AND RELEASES ENERGY DURING IDLE STROKE.
The main function of a flywheel is to smoothen out variations in the speed of a shaft caused by torque fluctuations.
flywheel does not maintain a constant speed; it simply reduces the fluctuation of speed.
a flywheel controls the speed variations caused by the fluctuation of the engine turning moment during each cycle of operation.
FLYWHEEL IS MADE UP OF………
flywheel made up of cast iron has more mass for same values of energy storage compared with all other materials. It is because of high density and less strength of cast iron. It is followed by, steel and E-glass fibre composite.
The flywheel position is between engine and clutch patch to starter.
flywheel connects the rotation from engine to clutch plate to the transmission.
Flywheel also makes the crankshaft to move in a motion to make the engine work from starter.
Governor is a mechanical device which is used to regulatethe mean speed of the engine, when there are variations in the load.
the governor automatically controls the supply of working fluid to the engine with the varying load condition and keeps the mean speed within certain limits.
when the load on an engine increases, its speed decreases, therefore it increases the supply of working fluid.
On the other hand, when the load on the engine decreases, its speed increases and thus less working fluid is supplied.
BY- TRISHAM GARG
MM UNIVERSITY MULLANA
CONTACT NUMBER - 8059495599
Propeller shaft is a circular shaft which is used to transmit the power or rotational motion from the gear box to the final drive.
The propeller shaft as the name suggest “ propels the vehicle.
Air Suspension System is commonly use in BMW,Mercedes,Audi types luxurious types Cars for protect from damaging, increasing life of the vehicle ,increases the handling , increases comfort of passengers and many more..
So according to me if you remove the suspension system, then you feel like in bull-cart in Audi, Mercedes, BMW type luxurious cars . The only diffrence is speed.
So the scope of Suspension System is Too Bright !!!
UNIT-1-VEHICLE STRUCTURE AND ENGINES.pptShanmathyAR2
VEHICLE STRUCTURE AND ENGINES
Types of automobiles, vehicle construction and different layouts, chassis, frame and body, resistances to vehicle aerodynamics (various resistances and moments involved), IC engines-components functions and materials, variable valve timing (VVT).
FLYWHEEL AND GOVERNORS
A flywheel is a mechanical device specifically designed to efficiently store rotational energy.
IT STORES ENERGY DURING POWER STROKE AND RELEASES ENERGY DURING IDLE STROKE.
The main function of a flywheel is to smoothen out variations in the speed of a shaft caused by torque fluctuations.
flywheel does not maintain a constant speed; it simply reduces the fluctuation of speed.
a flywheel controls the speed variations caused by the fluctuation of the engine turning moment during each cycle of operation.
FLYWHEEL IS MADE UP OF………
flywheel made up of cast iron has more mass for same values of energy storage compared with all other materials. It is because of high density and less strength of cast iron. It is followed by, steel and E-glass fibre composite.
The flywheel position is between engine and clutch patch to starter.
flywheel connects the rotation from engine to clutch plate to the transmission.
Flywheel also makes the crankshaft to move in a motion to make the engine work from starter.
Governor is a mechanical device which is used to regulatethe mean speed of the engine, when there are variations in the load.
the governor automatically controls the supply of working fluid to the engine with the varying load condition and keeps the mean speed within certain limits.
when the load on an engine increases, its speed decreases, therefore it increases the supply of working fluid.
On the other hand, when the load on the engine decreases, its speed increases and thus less working fluid is supplied.
BY- TRISHAM GARG
MM UNIVERSITY MULLANA
CONTACT NUMBER - 8059495599
Recruiting in the Digital Age: A Social Media MasterclassLuanWise
In this masterclass, presented at the Global HR Summit on 5th June 2024, Luan Wise explored the essential features of social media platforms that support talent acquisition, including LinkedIn, Facebook, Instagram, X (formerly Twitter) and TikTok.
What is the TDS Return Filing Due Date for FY 2024-25.pdfseoforlegalpillers
It is crucial for the taxpayers to understand about the TDS Return Filing Due Date, so that they can fulfill your TDS obligations efficiently. Taxpayers can avoid penalties by sticking to the deadlines and by accurate filing of TDS. Timely filing of TDS will make sure about the availability of tax credits. You can also seek the professional guidance of experts like Legal Pillers for timely filing of the TDS Return.
"𝑩𝑬𝑮𝑼𝑵 𝑾𝑰𝑻𝑯 𝑻𝑱 𝑰𝑺 𝑯𝑨𝑳𝑭 𝑫𝑶𝑵𝑬"
𝐓𝐉 𝐂𝐨𝐦𝐬 (𝐓𝐉 𝐂𝐨𝐦𝐦𝐮𝐧𝐢𝐜𝐚𝐭𝐢𝐨𝐧𝐬) is a professional event agency that includes experts in the event-organizing market in Vietnam, Korea, and ASEAN countries. We provide unlimited types of events from Music concerts, Fan meetings, and Culture festivals to Corporate events, Internal company events, Golf tournaments, MICE events, and Exhibitions.
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Sports events - Golf competitions/billiards competitions/company sports events: dynamic and challenging
⭐ 𝐅𝐞𝐚𝐭𝐮𝐫𝐞𝐝 𝐩𝐫𝐨𝐣𝐞𝐜𝐭𝐬:
➢ 2024 BAEKHYUN [Lonsdaleite] IN HO CHI MINH
➢ SUPER JUNIOR-L.S.S. THE SHOW : Th3ee Guys in HO CHI MINH
➢FreenBecky 1st Fan Meeting in Vietnam
➢CHILDREN ART EXHIBITION 2024: BEYOND BARRIERS
➢ WOW K-Music Festival 2023
➢ Winner [CROSS] Tour in HCM
➢ Super Show 9 in HCM with Super Junior
➢ HCMC - Gyeongsangbuk-do Culture and Tourism Festival
➢ Korean Vietnam Partnership - Fair with LG
➢ Korean President visits Samsung Electronics R&D Center
➢ Vietnam Food Expo with Lotte Wellfood
"𝐄𝐯𝐞𝐫𝐲 𝐞𝐯𝐞𝐧𝐭 𝐢𝐬 𝐚 𝐬𝐭𝐨𝐫𝐲, 𝐚 𝐬𝐩𝐞𝐜𝐢𝐚𝐥 𝐣𝐨𝐮𝐫𝐧𝐞𝐲. 𝐖𝐞 𝐚𝐥𝐰𝐚𝐲𝐬 𝐛𝐞𝐥𝐢𝐞𝐯𝐞 𝐭𝐡𝐚𝐭 𝐬𝐡𝐨𝐫𝐭𝐥𝐲 𝐲𝐨𝐮 𝐰𝐢𝐥𝐥 𝐛𝐞 𝐚 𝐩𝐚𝐫𝐭 𝐨𝐟 𝐨𝐮𝐫 𝐬𝐭𝐨𝐫𝐢𝐞𝐬."
The key differences between the MDR and IVDR in the EUAllensmith572606
In the European Union (EU), two significant regulations have been introduced to enhance the safety and effectiveness of medical devices – the In Vitro Diagnostic Regulation (IVDR) and the Medical Device Regulation (MDR).
https://mavenprofserv.com/comparison-and-highlighting-of-the-key-differences-between-the-mdr-and-ivdr-in-the-eu/
Improving profitability for small businessBen Wann
In this comprehensive presentation, we will explore strategies and practical tips for enhancing profitability in small businesses. Tailored to meet the unique challenges faced by small enterprises, this session covers various aspects that directly impact the bottom line. Attendees will learn how to optimize operational efficiency, manage expenses, and increase revenue through innovative marketing and customer engagement techniques.
RMD24 | Retail media: hoe zet je dit in als je geen AH of Unilever bent? Heid...BBPMedia1
Grote partijen zijn al een tijdje onderweg met retail media. Ondertussen worden in dit domein ook de kansen zichtbaar voor andere spelers in de markt. Maar met die kansen ontstaan ook vragen: Zelf retail media worden of erop adverteren? In welke fase van de funnel past het en hoe integreer je het in een mediaplan? Wat is nu precies het verschil met marketplaces en Programmatic ads? In dit half uur beslechten we de dilemma's en krijg je antwoorden op wanneer het voor jou tijd is om de volgende stap te zetten.
Implicitly or explicitly all competing businesses employ a strategy to select a mix
of marketing resources. Formulating such competitive strategies fundamentally
involves recognizing relationships between elements of the marketing mix (e.g.,
price and product quality), as well as assessing competitive and market conditions
(i.e., industry structure in the language of economics).
LA HUG - Video Testimonials with Chynna Morgan - June 2024Lital Barkan
Have you ever heard that user-generated content or video testimonials can take your brand to the next level? We will explore how you can effectively use video testimonials to leverage and boost your sales, content strategy, and increase your CRM data.🤯
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1. How to capture video testimonials that convert from your audience 🎥
2. How to leverage your testimonials to boost your sales 💲
3. How you can capture more CRM data to understand your audience better through video testimonials. 📊
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3.0 Project 2_ Developing My Brand Identity Kit.pptxtanyjahb
A personal brand exploration presentation summarizes an individual's unique qualities and goals, covering strengths, values, passions, and target audience. It helps individuals understand what makes them stand out, their desired image, and how they aim to achieve it.
[Note: This is a partial preview. To download this presentation, visit:
https://www.oeconsulting.com.sg/training-presentations]
Sustainability has become an increasingly critical topic as the world recognizes the need to protect our planet and its resources for future generations. Sustainability means meeting our current needs without compromising the ability of future generations to meet theirs. It involves long-term planning and consideration of the consequences of our actions. The goal is to create strategies that ensure the long-term viability of People, Planet, and Profit.
Leading companies such as Nike, Toyota, and Siemens are prioritizing sustainable innovation in their business models, setting an example for others to follow. In this Sustainability training presentation, you will learn key concepts, principles, and practices of sustainability applicable across industries. This training aims to create awareness and educate employees, senior executives, consultants, and other key stakeholders, including investors, policymakers, and supply chain partners, on the importance and implementation of sustainability.
LEARNING OBJECTIVES
1. Develop a comprehensive understanding of the fundamental principles and concepts that form the foundation of sustainability within corporate environments.
2. Explore the sustainability implementation model, focusing on effective measures and reporting strategies to track and communicate sustainability efforts.
3. Identify and define best practices and critical success factors essential for achieving sustainability goals within organizations.
CONTENTS
1. Introduction and Key Concepts of Sustainability
2. Principles and Practices of Sustainability
3. Measures and Reporting in Sustainability
4. Sustainability Implementation & Best Practices
To download the complete presentation, visit: https://www.oeconsulting.com.sg/training-presentations
7. Figure 31-1 Identification of the parts of a valve.
8.
9.
10.
11. Figure 31-2 Typical valve spring and related components. Dual valve springs are used to reduce valve train vibrations and a spring seat is used to protect aluminum heads.
12. Figure 31-3 The intake valve is larger than the exhaust valve because the intake charge is being drawn into the combustion chamber at a low speed due to differences in pressure between atmospheric pressure and the pressure (vacuum) inside the cylinder. The exhaust is actually pushed out by the piston and, therefore, the size of the valve does not need to be as large, leaving more room in the cylinder head for the larger intake valve.
13.
14.
15.
16.
17. Figure 31-4 Inertia welded valve stem and head before machining.
18.
19.
20. Figure 31-5 A sodium-filled valve uses a hollow stem, which is partially filled with metallic sodium (a liquid when hot) to conduct heat away from the head of the valve.
47. Figure 31-13 A retainer and two split keepers hold the spring in place on the valve. A spring seat is used on aluminum heads. Otherwise, the spring seat is a machined area in the head.
48. Figure 31-14 Valve spring types ( left to right ): coil spring with equally spaced coils; spring with damper inside spring coil; closely spaced spring with a damper; taper wound coil spring.
49. Figure 31-15 Valve springs maintain tension in the valve train when the valve is open to prevent valve float, but must not exert so much tension that the cam lobes and lifters begin to wear.
50.
51.
52.
53.
54.
55.
56.
57.
58.
59. Figure 31-16 All valve springs should be checked for squareness by using a square on a flat surface and rotating the spring while checking. The spring should be replaced if more than 1/16 in. (1.6 mm) is measured between the top of the spring and the square.
60. Figure 31-17 One popular type of valve spring tester used to measure the compressed force of valve springs. Specifications usually include (1) free height (height without being compressed), (2) pressure at installed height with the valve closed, and (3) pressure with the valve open to the height specified.
64. Figure 31-18 Valve keepers (also called locks) are tapered so they wedge into a tapered hole in the retainer.
65.
66.
67.
68.
69.
70.
71. Figure 31-19 Notice that there is no gap between the two keepers (ends butted together). As a result, the valve is free to rotate because the retainer applies a force, holding the keepers in place but not tight against the stem of the valve. Most engines, however, do not use free rotators and, therefore, have a gap between the keepers.
72. Figure 31-20 Type of valve rotator operation. Ball-type operation is on the left and spring-type operation is on the right.
85. Figure 31-21 Resurfacing the face of a valve. Both the valve and the grinder stone or disc are turned to ensure a smooth surface finish on the face of the valve.
86.
87.
88.
89. Figure 31-22 Never use a valve that has been ground to a sharp edge. This weakens the valve and increases the chance of valve face burning.
95. Figure 31-24 Grinding a 45-degree angle establishes the valve seat in the combustion chamber.
96.
97.
98. Figure 31-25 Some vehicle manufacturers recommend that the valve face be resurfaced at a 44-degree angle and the valve seat at a 45-degree angle. This 1-degree difference is known as the interference angle.
99.
100.
101. Figure 31-26 The seat must contact evenly around the valve face. For good service life, both margin and overhang should be at least 1/32 in. (0.8 mm).
102.
103.
104.
105. Figure 31-27 Grinding a 60-degree angle removes metal from the bottom to raise and narrow the seat.
106. Figure 31-28 Grinding a 30-degree angle removes metal from the top to lower and narrow the seat.
107. Figure 31-29 A typical three-angle valve job using 30-, 45-, and 60-degree stones or cutters.
125. Figure 31-31 Checking valve seat concentricity using a dial indicator.
126. Figure 31-32 Typical dial indicator type of micrometer for measuring valve seat concentricity.
127.
128.
129.
130.
131.
132. Figure 31-33 After the valve face and the valve seat are ground (reconditioned), lapping compound is used to smooth the contact area between the two mating surfaces. Notice that the contact is toward the top of the face. For maximum life, the contact should be in the middle of the face.
149. Figure 31-35 All aluminum cylinder heads use valve seat inserts. If an integral valve seat (cast-iron head) is worn, it can be replaced with a replacement valve seat by machining a pocket (counterbore) to make a place for the new insert seat.
150.
151.
152.
153. Figure 31-36 Insert valve seats are rings of metal driven into the head.
170. Figure 31-37 Valve stem height is measured from the spring seat to the tip of the valve after the valve seat and valve face have been refinished. If the valve stem height is too high, up to 0.02 in. can be ground from the tips of most valves.
183. Figure 31-40 Engine vacuum can draw oil past the valve guides and into the combustion chamber. The use of valve stem seals limits the amount of oil that is drawn into the engine. If the seals are defective, excessive blue (oil) smoke is most often observed during engine start-up.
184. Figure 31-41 Engine oil can also be drawn past the exhaust valve guide because of a small vacuum created by the flow of exhaust gases. Any oil drawn past the guide would simply be forced out through the exhaust system and not enter the engine. Some engine manufacturers do not use valve stem seals on the exhaust valves.
185.
186.
187. Figure 31-42 Umbrella seals install over the valve stems and cover the guide.
188. Figure 31-43 A small square cut O-ring is installed under the retainer in a groove in the valve under the groove(s) used for the keepers (locks).
189. Figure 31-44 Positive valve stem seals are the most effective type because they remain stationary on the valve guide and wipe the oil from the stem as the valve moves up and down.
190. Figure 31-45 The positive valve stem seal is installed on the valve guide.
191. Figure 31-46 An assortment of shapes, colors, and materials of positive valve stem seals.
199. Figure 31-42 Umbrella seals install over the valve stems and cover the guide.
200. Figure 31-43 A small square cut O-ring is installed under the retainer in a groove in the valve under the groove(s) used for the keepers (locks).
201. Figure 31-44 Positive valve stem seals are the most effective type because they remain stationary on the valve guide and wipe the oil from the stem as the valve moves up and down.
202. Figure 31-45 The positive valve stem seal is installed on the valve guide.
203. Figure 31-46 An assortment of shapes, colors, and materials of positive valve stem seals.
204. INSTALLING A NEW VALVE SEAT 1 After the valve guide has been replaced or checked for being within specification, insert a pilot into the valve guide.
205. INSTALLING A NEW VALVE SEAT 2 Level the bubble on the pilot by moving the cylinder head, which is clamped to a seat/guide machine.
206. INSTALLING A NEW VALVE SEAT 3 Select the proper guide for the application. Consult guide manufacturer’s literature for recommendations.
207. INSTALLING A NEW VALVE SEAT 4 Select the correct cutter and check that the cutting bits are sharp.
208. INSTALLING A NEW VALVE SEAT 5 Carefully measure the exact outside diameter (O.D.) of the valve seat.
209. INSTALLING A NEW VALVE SEAT 6 Adjust the depth of the cutter bit to achieve the specified interference fit for the valve seat.
210. INSTALLING A NEW VALVE SEAT 7 Install the pilot into the valve guide to support the seat cutter.
211. INSTALLING A NEW VALVE SEAT 8 Install the seat cutter onto the pilot.
212. INSTALLING A NEW VALVE SEAT 9 Adjust the depth of cut, using the new valve seat to set it to the same depth as the thickness of the seat.
213. INSTALLING A NEW VALVE SEAT 10 With the cylinder head still firmly attached to the seat and guide machine, start the cutter motor and cut the head until it reaches the stop.
214. INSTALLING A NEW VALVE SEAT 11 The finish cut valve seat pocket. Be sure to use a vacuum to remove all of the metal shavings from the cutting operation.
215. INSTALLING A NEW VALVE SEAT 12 Place the chilled valve seat over the pilot being sure that the chamfer is facing toward the head as shown.
216. INSTALLING A NEW VALVE SEAT 13 Install the correct size driver onto the valve seat.
217. INSTALLING A NEW VALVE SEAT 14 Using the air hammer or press, press the valve seat into the valve pocket.
218. INSTALLING A NEW VALVE SEAT 15 A new valve seat is now ready to be machined or cut.
219.
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Editor's Notes
Figure 31-1 Identification of the parts of a valve.
Figure 31-2 Typical valve spring and related components. Dual valve springs are used to reduce valve train vibrations and a spring seat is used to protect aluminum heads.
Figure 31-3 The intake valve is larger than the exhaust valve because the intake charge is being drawn into the combustion chamber at a low speed due to differences in pressure between atmospheric pressure and the pressure (vacuum) inside the cylinder. The exhaust is actually pushed out by the piston and, therefore, the size of the valve does not need to be as large, leaving more room in the cylinder head for the larger intake valve.
Figure 31-4 Inertia welded valve stem and head before machining.
Figure 31-5 A sodium-filled valve uses a hollow stem, which is partially filled with metallic sodium (a liquid when hot) to conduct heat away from the head of the valve.
Figure 31-6 Integral valve seats are machined directly into the cast-iron cylinder head and are induction hardened to prevent wear.
Figure 31-7 Insert valve seats are a separate part that is interference fitted to a counterbore in the cylinder head.
Figure 31-8 Typical intake valve seat wear.
Figure 31-9 Carbon deposits on the intake valve are often caused by oil getting past the valve stems or fuel deposits.
Figure 31-10 Excessive wear of the valve stem or guide can cause the valve to seat in a cocked position.
Figure 31-11 Valve face guttering caused by thermal shock.
Figure 31-12 Note the broken piston caused by a valve breaking from the stem.
Figure 31-13 A retainer and two split keepers hold the spring in place on the valve. A spring seat is used on aluminum heads. Otherwise, the spring seat is a machined area in the head.
Figure 31-14 Valve spring types ( left to right ): coil spring with equally spaced coils; spring with damper inside spring coil; closely spaced spring with a damper; taper wound coil spring.
Figure 31-15 Valve springs maintain tension in the valve train when the valve is open to prevent valve float, but must not exert so much tension that the cam lobes and lifters begin to wear.
Figure 31-16 All valve springs should be checked for squareness by using a square on a flat surface and rotating the spring while checking. The spring should be replaced if more than 1/16 in. (1.6 mm) is measured between the top of the spring and the square.
Figure 31-17 One popular type of valve spring tester used to measure the compressed force of valve springs. Specifications usually include (1) free height (height without being compressed), (2) pressure at installed height with the valve closed, and (3) pressure with the valve open to the height specified.
Figure 31-18 Valve keepers (also called locks) are tapered so they wedge into a tapered hole in the retainer.
Figure 31-19 Notice that there is no gap between the two keepers (ends butted together). As a result, the valve is free to rotate because the retainer applies a force, holding the keepers in place but not tight against the stem of the valve. Most engines, however, do not use free rotators and, therefore, have a gap between the keepers.
Figure 31-20 Type of valve rotator operation. Ball-type operation is on the left and spring-type operation is on the right.
Figure 31-21 Resurfacing the face of a valve. Both the valve and the grinder stone or disc are turned to ensure a smooth surface finish on the face of the valve.
Figure 31-22 Never use a valve that has been ground to a sharp edge. This weakens the valve and increases the chance of valve face burning.
Figure 31-24 Grinding a 45-degree angle establishes the valve seat in the combustion chamber.
Figure 31-25 Some vehicle manufacturers recommend that the valve face be resurfaced at a 44-degree angle and the valve seat at a 45-degree angle. This 1-degree difference is known as the interference angle.
Figure 31-26 The seat must contact evenly around the valve face. For good service life, both margin and overhang should be at least 1/32 in. (0.8 mm).
Figure 31-27 Grinding a 60-degree angle removes metal from the bottom to raise and narrow the seat.
Figure 31-28 Grinding a 30-degree angle removes metal from the top to lower and narrow the seat.
Figure 31-29 A typical three-angle valve job using 30-, 45-, and 60-degree stones or cutters.
Figure 31-30 A valve guide pilot being used to support a valve seat cutter.
Figure 31-31 Checking valve seat concentricity using a dial indicator.
Figure 31-32 Typical dial indicator type of micrometer for measuring valve seat concentricity.
Figure 31-33 After the valve face and the valve seat are ground (reconditioned), lapping compound is used to smooth the contact area between the two mating surfaces. Notice that the contact is toward the top of the face. For maximum life, the contact should be in the middle of the face.
Figure 31-34 A cutter is used to remove metal and form the valve seat angles.
Figure 31-35 All aluminum cylinder heads use valve seat inserts. If an integral valve seat (cast-iron head) is worn, it can be replaced with a replacement valve seat by machining a pocket (counterbore) to make a place for the new insert seat.
Figure 31-36 Insert valve seats are rings of metal driven into the head.
Figure 31-37 Valve stem height is measured from the spring seat to the tip of the valve after the valve seat and valve face have been refinished. If the valve stem height is too high, up to 0.02 in. can be ground from the tips of most valves.
Figure 31-38 Installed height is determined by measuring the distance from the spring seat to the bottom of the valve spring retainer.
Figure 31-39 Valve spring inserts are used to restore proper installed height.
Figure 31-40 Engine vacuum can draw oil past the valve guides and into the combustion chamber. The use of valve stem seals limits the amount of oil that is drawn into the engine. If the seals are defective, excessive blue (oil) smoke is most often observed during engine start-up.
Figure 31-41 Engine oil can also be drawn past the exhaust valve guide because of a small vacuum created by the flow of exhaust gases. Any oil drawn past the guide would simply be forced out through the exhaust system and not enter the engine. Some engine manufacturers do not use valve stem seals on the exhaust valves.
Figure 31-42 Umbrella seals install over the valve stems and cover the guide.
Figure 31-43 A small square cut O-ring is installed under the retainer in a groove in the valve under the groove(s) used for the keepers (locks).
Figure 31-44 Positive valve stem seals are the most effective type because they remain stationary on the valve guide and wipe the oil from the stem as the valve moves up and down.
Figure 31-45 The positive valve stem seal is installed on the valve guide.
Figure 31-46 An assortment of shapes, colors, and materials of positive valve stem seals.
Figure 31-42 Umbrella seals install over the valve stems and cover the guide.
Figure 31-43 A small square cut O-ring is installed under the retainer in a groove in the valve under the groove(s) used for the keepers (locks).
Figure 31-44 Positive valve stem seals are the most effective type because they remain stationary on the valve guide and wipe the oil from the stem as the valve moves up and down.
Figure 31-45 The positive valve stem seal is installed on the valve guide.
Figure 31-46 An assortment of shapes, colors, and materials of positive valve stem seals.
INSTALLING A NEW VALVE SEAT 1 After the valve guide has been replaced or checked for being within specification, insert a pilot into the valve guide.
INSTALLING A NEW VALVE SEAT 2 Level the bubble on the pilot by moving the cylinder head, which is clamped to a seat/guide machine.
INSTALLING A NEW VALVE SEAT 3 Select the proper guide for the application. Consult guide manufacturer’s literature for recommendations.
INSTALLING A NEW VALVE SEAT 4 Select the correct cutter and check that the cutting bits are sharp.
INSTALLING A NEW VALVE SEAT 5 Carefully measure the exact outside diameter (O.D.) of the valve seat.
INSTALLING A NEW VALVE SEAT 6 Adjust the depth of the cutter bit to achieve the specified interference fit for the valve seat.
INSTALLING A NEW VALVE SEAT 7 Install the pilot into the valve guide to support the seat cutter.
INSTALLING A NEW VALVE SEAT 8 Install the seat cutter onto the pilot.
INSTALLING A NEW VALVE SEAT 9 Adjust the depth of cut, using the new valve seat to set it to the same depth as the thickness of the seat.
INSTALLING A NEW VALVE SEAT 10 With the cylinder head still firmly attached to the seat and guide machine, start the cutter motor and cut the head until it reaches the stop.
INSTALLING A NEW VALVE SEAT 11 The finish cut valve seat pocket. Be sure to use a vacuum to remove all of the metal shavings from the cutting operation.
INSTALLING A NEW VALVE SEAT 12 Place the chilled valve seat over the pilot being sure that the chamfer is facing toward the head as shown.
INSTALLING A NEW VALVE SEAT 13 Install the correct size driver onto the valve seat.
INSTALLING A NEW VALVE SEAT 14 Using the air hammer or press, press the valve seat into the valve pocket.
INSTALLING A NEW VALVE SEAT 15 A new valve seat is now ready to be machined or cut.