Oil Pump Priming Instructions
Monday, November 12th, 2012
Posted in Marine Engines, Technical Articles | Comments Closed
Our Remanufactured Marine Longblock Engines have a Max bore size of .060″ over. The normal manufacturing process includes cutting .040″ then checking cylinder wall finish, and if needed cutting another .020″ maximum. NOTE – All of the cylinder bores will be the same diameter.
People generally have a misconception of cylinder bore that more is bad, which is not necessarily true. While a .060 bore or .040 for that matter has less “meat” in the cylinder walls than it started with originally-it does not negatively affect engine performance or longevity. GM’s OE cylinder wall thickness varies from engine model to engine model..and even from block to block depending on casting shifts..or mold design. The production process for our remanufactured longblocks monitors casting shifts and uses a type of ultrasound machine to measure thickness to make sure it is in our allowed range on questionable blocks.
BOTTOM LINE: Cylinder Wall Thickness is more important than how much the cylinder is bored out.
Using the links below you can review more information regarding changing out a longblock. Let us know if you need any further technical information, we will be glad to assist!
Link to Block Code/Serial Number Location
Tags:marine engines, remanufactured longblocks
Posted in Alphabetical List of Articles, Technical Articles | Comments Closed
CATEGORY | DESCRIPTION |
General Marine Technical Topics | General marine topics such as “Is WINTERIZING Something I Can Do Myself”, “What is Marine Corrosion And How Can I Prevent It”, and “Should I Fog My Marine Engine”. |
Marine Cooling Systems | Learn about the benefits of closed cooling, 1/2 versus full closed cooling systems, how to install a thru hull fitting, installing closed cooling on an old engine, and much more. |
Boat Engine & Repowering Topics | Learn about marine engine topics ranging from how do I replace my engine, my accessories are still good can I just replace the block, are automotive and marine engines the same, do the new EPA regulations apply to marine engines, is the 454 different from a 496, etc. |
Marine Exhaust Systems | Learn about marine exhaust topics such as when you should replace your exhaust, aluminum versus cast iron, are coatings beneficial, do marine gaskets require sealant, how tight to torque risers, etc. |
Mercury and Mercruiser Topics | General Mercruiser topics ranging from Common Mercruiser Service Bulletins, how to find your Mercruiser serial number, where to find Mercruiser installation drawings, and what is Mercury CPO product, how are Mercruiser engines affected by the new EPA regulations. |
PPT Articles & Categories | A variety of Marine Article Topics that are supported by Performance Product Technologies. |
Propellers Fundamentals | Find out everything you ever wanted to know about propellers. |
Sterndrives & Transom Assemblies | Learn more about Sterndrives such as how to if you have an Alpha Gen 1 or Alpha Gen 2, what is your gear ratio, how to adjust your shift cable, etc. |
Suzuki Outboards | General Suzuki topics such as model identification, year model serial number to model year reference charts, service tips, etc. |
Velvet Drive Transmissions | Includes product diagrams, parts lists, and model pricing for Inline, Direct Drive, V Drive, and Down Angle Borg Warner/Velvet Drive Marine Transmissions. |
Yamaha Outboard Motors | Includes Yamaha product diagrams, parts lists, and model pricing for 2 stroke and 4 stroke outboard motors. |
ZF Hurth Transmissions | Includes product diagrams, parts lists, and model pricing for Inline, Direct Drive, V Drive, and Down Angle Borg Warner/Velvet Drive Marine Transmissions. |
Our Technical Boating Library features a wealth of information for both novice and veteran boating enthusiasts, including easy-to-follow how-to videos and valuable articles. Search for the information you need by category, then select the associated topic to find answers to common boating related questions. Whether you’re looking for articles on replacing a Marine Engine, Quicksilver Marine Parts or propeller fundamentals you will find it at PPT. However, if you still can’t find the information you need in our library, please don’t hesitate to contact us via phone or email (405) 533-3812 or [email protected]. Our experienced and friendly staff is always available to answer your questions and guide you down the right path, from finding the right Yamaha marine parts to installing a wakeboard tower.
Performance Product Technologies offers more than 50 combined years of technical experience and knowledge in the boating and marine parts industry. We understand the design and engineering of everything from long block engines to Volvo marine parts and accessories, making us a reliable source for insight and advice on the best parts and options for your boat and boat engine.
Tags:marine cooler, marine engines, marine exhaust, marine parts, mercruiser, sterndrives, technical support, transom assemblies, volvo penta
Posted in Technical Articles | No Comments »
CATEGORY | DESCRIPTION |
Awarded Patents | Read more detail on our company background and awarded patents. |
Crusader | Performance Product Technologies can handle ALL of your repower needs, from the 300 hp 5.7L up to the 420 hp 8.1L. PCM… |
Cylinder Head Products | Search for Cylinder Heads |
Marine Carburetors | Search for Marine Carburetor’s |
Marine Cooling Systems | When it comes to protecting your engine investment, the cooling and exhaust systems are undoubtedly at the top of the list… |
Marine Engine Options | Performance Product Technologies can handle ALL of your repower needs, from the 300 hp 5.7L up to the 420 hp 8.1L. PCM… |
Marine Exhaust | Looking for new marine exhaust manifolds or marine exhaust risers that will provide superior performance and power? At PPT, we offer… |
Marine Generators | If you’re tired of the high costs associated with replacing your marine exhaust manifolds and risers every few years… |
Marine Part Technical Tips | Select this link to view a huge library of Marine Technical Tips on exhaust & cooling systems, engines, drives and much more ………….. |
Marine Parts | When it comes time to replace your existing marine parts, boat parts, and marine engines, PPT offers unmatched service and support. Find discount marine parts online at the PPT boating superstore. |
Marine Power | Performance Product Technologies can handle ALL of your repower needs, from the 300 hp 5.7L up to the 420 hp 8.1L. PCM… |
Marine Propellers | PPT offers the complete lineup from Marine Power. Marine Power originated by Chares Pollion in the late 1950’s having… |
Marine Transmissions | When it comes to getting the right marine transmission for your boat, PPT is your one-stop source. Performance Product… |
Mercruiser Parts | We offer Mercruiser engines and drive or engine and transmission package specials. Performance Product Technologies… |
Sierra Carburetors | A carburetor replacement table for finding the correct Sierra remanufactured carburetor for your engine… |
Sterndrives | When you’re looking for a rebuilt OMC Sterndrive, trust Performance Product Technologies to offer the best quality for… |
Volvo Penta Parts | When it comes to getting Volvo Penta parts, including everything from Volvo Penta exhaust manifolds to Volvo Penta… |
Posted in Alphabetical List of Articles, Technical Articles | No Comments »
CATEGORY | DESCRIPTION |
Mercury Certified Pre-Owned | What is Mercury CPO product? Does CPO product have a warranty? Why is it cheaper? |
Mercruiser Gen II Cool Fuel Pump Replacements | The Gen II cool fuel pump is being replaced by pump/cooler kits. This service bulletin covers the various available options. |
Mercruiser Gen III Cool Fuel Module | A new Gen III cool fuel module is being introduced to replace the existing Gen III module. Engines with serial numbers above the range listed are equipped with the new module from the factory. The primary difference between the designs is the method of connecting the cooling water hoses to the module. |
Mercruiser Ignition Control Module Kit’s | Replacement Kits for Thunderbolt IV Ignition Control Module |
Mercruiser Installation Drawings | Find all the latest Mercruiser installations drawings for both inboards and sterndrives. |
Mercruiser Maintenance Parts | Find all your Mercruiser Maintenance Parts from Mercruiser Cooling System Impellers to Mercruiser Propellers, to Mercruiser Electrical Accessories. |
Mercury Marine Part Number Format | Mercury Marine utilizes a specific format system with their Inboard & Outboard Parts. This article covers the proper formatting and part identification used with Mercury Marine & MerCruiser Part Numbers for both 2 stroke & 4 stroke outboard models as well as Sterndrives and Inboards |
Mercruiser Rigging Info | Mercruiser Rigging Information |
Mercruiser Special Tools | Find your Mercruiser tools including bellows expansion tools, hinge pin tools and engine diagnostic computers. |
Mercruiser Serpentine Belt Changes | I had the old plastic Sea Water pump pulley that was discontinued. What are my options for replacing this pulley? |
Mercruiser Seawater Pump Changes | I have the old 2 piece seawater pump housing. What is the latest seawater pump housing that replaces mine? |
Mercruiser Shift Interrupt Switch Changes | I Need to Replace My Mercrusier Shift Interrupt Switch but The Switch Is No Longer Available. What Do I Do? |
Mercruiser Serial Numbers | Where to find your Mercruiser serial number. |
Mercury Outboard Serial Tag Location | Where to find your Mercury Outboard Motor serial number/tag location. |
Mercury Marine Smartcraft & VesselView Products | Mercury Marine SmartCraft & VesselView Mobile Products and Information. |
Mercury Marine Smartcraft Engine Guardian System Alarms | How to distinguish the various audible alarms associated with Mercury Marine’s Engine Guardian protection system. |
Mercruiser Thermostat Housing No Longer Available | I have the older Mercruiser p/n 16413 type thermostat housing which is no longer available. What is the part number of the correct replacement thermostat housing? |
Mercruiser Stainless Thermostat Housing Changes | I have the older Mercruiser p/n 80123 type thermostat housing which is no longer available. What is the part number of the correct replacement thermostat housing? |
Mercruiser Vapor Locking Bulletin | How to Properly Diagnose the Casue of Certain Mercruiser Marine Engine Vapor Locking Problems. |
Mercury Mercruiser Warranty | Find all the information regarding standard and additional product warranty options for both Mercury and Mercruiser products. |
Posted in Alphabetical List of Articles, Technical Articles | No Comments »
How do you identify a 1996 Vortec 4,3 vs a 1995 pre-Vortec model? How do you determine a standard vs opposite rotation boat engine? How do you properly size a marine carburetor? How do you repower a boat? Find answer to these and tons of other technical marine engine related product topics. This section of the PPT Technical Marine Library focuses on products and topics related to Marine Longblocks, Complete Bobtail Engines, and drop in marine motors. This article library not only covers but focuses in on a variety of additional topics such as the recent EPA regulations, finding additional horsepower for your boat, determining the condition of your engine, and many other related topics. Performance Product Technologies covers information for a variety of manufacturers such as;
CATEGORY | DESCRIPTION |
**Repowering Options** | This tool will help you find and understand the available options when repowering your boat. |
3.0L Engines | How to select the correct 2.5L or 3.0L engine |
3.0L Longblocks – Reman or New? | My 3.0L Block is Cracked. Should I Purchase a New Longblock or Remanufactured? |
3.7L/470 Marine Engine Repowers | My Mercruiser 470 Engine Is On Its Last Leg. What Options Can I Consider to Replace It? |
4.3L Engines | How to select the correct new 4.3L marine longblock |
5.0L/5.7L Engines | How do I select the correct new 5.0L or 5.7L longblock? |
7.4L/8.2L Engines | How do I select the correct 454/502 (7.4L/8.2L) new marine longblock? |
7.4L/8.2L Versus 496 Repower’s | Replacing your 454 marine engine with the newer 496 engine |
7.4L (L29) vs 454 Mag Models | How to Identify the 310 Hp L29 454 Engine Model vs Other 330 Hp & 385 Hp 454 Engine Models |
Auto vs. Marine | Are automotive and marine engines the same? |
Block Code Indentification 4 Cyl | Mercruiser Engine Block Code Identification Table For Properly Identifying Your Mercrusier 4 Cylinder Marine Engine. |
Block Code Indentification 6 Cyl | Mercruiser Engine Block Code Identification Table For Properly Identifying Your Mercrusier 6 Cylinder Marine Engine. |
Block Code Indentification Small V8 | Mercruiser Engine Block Code Identification Table For Properly Identifying Your Mercrusier Small V8 Marine Engine. |
Block Code Indentification Big Block V8 | Mercruiser Engine Block Code Identification Table For Properly Identifying Your Mercrusier Big Block V8 Marine Engine. |
Break In Procedure for Marine Engines | Can I run my new engine at full throttle within the 1st hour or do I need to follow a prescribed procedure in breaking the engine in correctly? |
How to size a marine Carburetor | Will my boat go faster if I install a BIGGER carburetor? |
Compression Testing Your Marine Engine | How To Properly Test the Compression of Your Marine Engine |
Condition of Your Marine Engine (Part 1) | Condition of My Marine Engine? My Accessories Seem Fine So Should I Consider a New Longblock or Complete Bobtail? |
Condition of Your Marine Engine (Part 2) | Determining The Condition of My Marine Engine. Is a Compression Test as Good as a Cylinder Leak Down Test? |
Coupler Replacement on Marine Engine | How to Know if You Should Replace Your Engine Coupler. |
Cylinder Boring on Remanufactred Marine Engines | How much is considered acceptable for the cylinders to be bored on remanufactured longblocks? |
Drive Variations | Various Marine Drive Configurations |
Emissions Rules for New Marine Engines | The rules have changed dramatically regarding how new marine engines can be sold. Select this article to see how this effects your repowering options. |
Emissions Options for Repowering | What options do I have in replacing the engine in my boat knowing that the EPA started regulating marine engines for new and existing boats? |
Flame Arrestor | Will changing my Flame Arrestor make my boat go any faster? |
Inboard versus Sterndrive Identification | Is my boat an inboard or sterndrive? |
Marine Engines | Performance Product Technologies offers a variety of new and remanufactured marine engines for sale. How to determine the correct engine for your boat. |
Oil Pump Priming Instructions | How to prime the oil pump when installing a new longblock or marine engine. |
Repowering Your Boat | I really love my old boat but need a new engine. What do I need to know when repowering the boat? |
Repowering Your Boat (Newsletter) | Marine Engine Repowering Newsletter |
Rotation of a Marine Engine | How do I determine if my engine rotation is Left Hand or Right Hand? |
Remanufactured Marine Engines | How do I select the correct remanufactured marine longblock? |
Shortblock’s vs Longblock’s | Which is the better option a Shortblock or Longblock Marine Engine? |
Torque Vs. Horsepower | What makes a boat go faster horsepower or torque? |
Tags:carburetors, epa, horsepower, longblocks, marine engines, repowering
Posted in Alphabetical List of Articles, Marine Engines, Technical Articles | No Comments »
Search here to find a huge range of technical information including Closed Cooling Systems and whether you should consider a half system versus a full system, thru hull installation specifications, and raw water pump versus circulating pump differences. We cover technical cooling system information from OEM’s such as Mercruiser, Mercury Marine, Volvo Penta, Crusader and several other Marine Motor manufacturers.
CATEGORY | DESCRIPTION |
Antifreeze – What You Should Know | What is the difference between Ethylene glycol and Propylene glycol? |
Cooling Installation on an Old Engine | Tips for installing a Marine Closed Cooling system onto an older marine engine. |
Diagnosing Engine Overheat Problems | My marine engine is overheating. Could the water pump impeller be bad? How do I replace the impeller on my Marine Water Pump? |
Drain System Options | What are the different types of drain systems offered on Mercruiser Marine Engines? |
Dry Joint Exhaust Closed Cooling System | Flow Diagram & history of the Mercruiser Engine Dry Joint Exhaust and Closed Cooling System. |
Cooling System Tips | General trouble shooting and technical tips for marine cooling systems. |
Fresh Water Cooling – What is It? | What is the difference between a 1/2 and full closed cooling system? |
Fresh Water Cooling – The Benefits | Why should I consider adding a marine closed cooling system to my engine? |
Fresh Water Cooling – The Basics | Basic fundamentals of marine closed cooling systems. |
Fresh Water Cooling Maintenance | How to maintain marine closed cooling systems. |
Fresh Water Cooling Trouble Shooting | How to trouble shoot marine cooling systems. |
Marine Cooling Systems Newsletter | General Information Marine Cooling System Newsletter |
Premium vs Standard FWC Systems | What is the difference between the Premium and Standard Closed Cooling Systems? |
San Juan Closed/Freshwater Cooling Systems | San Juan Closed/Freshwater Cooling Systems |
Thru-Hull Installation | Installation information for installing a thru hull fitting on your boat. |
Warm Vs Cold Manifolds | What is the difference between “Warm Manifold and Cold Manifold” exhaust/cooling systems? |
Water Distribution Housing Options | Can you explain what the purpose is for Mercruiser’s Water Distribution Housing most of the Marine Engines are being equipped with today? |
Water Pump Impeller Failures | I’ve replaced my water pump impeller but my engine is still over heating. What am I missing? |
Posted in Alphabetical List of Articles, Technical Articles | No Comments »
CATEGORY | DESCRIPTION |
Battery Maintenance & Storage | How do I protect my battery for cold weather and storage? |
Boat Winterization | Winterization Q&A |
Buying Used “Pre-Owned” Boats | Inspection tips to assist you when looking to purchase a used boat |
Cold Weather Storage Concerns | How to avoid damage associated with extreme cold weather conditions |
Ethanol Fuel Concerns | How to avoid alcohol blended (Ethanol) induced engine damage |
Marine Engine Winterization | The basic “Winterization” fundamentals. |
Newsletter 9 05r1 | Winterization Newsletter |
Marine Corrosion | Marine Corrosion Information Newsletter |
Marine Corrosion Tips | Basic Fundmentals of Marine Corrosion |
Q&A Engine Fogging | What should I know about fogging my Marine Engine? |
Shrink Wrapping Your Boat | What are the main things to be aware of when considering shrink wrapping a boat for winter storage? |
Storing Your Boat | What is the most important factor when investigating boat storage? |
Towing Your Boat | What is the Dry Weight referring to when towing my boat? |
Posted in Alphabetical List of Articles, Technical Articles | No Comments »
ARTICLE |
DESCRIPTION |
Vazer Engine Specifications | Engine specification information for the Mercruiser Vazer engine. |
Mercruiser 3.0L Performance Spec’s | Mercruiser 3.0L/I4 engine specifications including horsepower, displacement, rpm, oil pressure, ignition timing, firing order, etc. |
Mercruiser 3.0L Engine Spec’s | Mercruiser 3.0L/I4 engine mechanical specifications including fastener torques, and engine manufacturing dimensions and tolerances. |
Mercruiser 3.0L Wiring | Mercruiser 3.0L Marine Engine Wiring Diagram |
Mercruiser 4.3L Performance Spec’s | Mercruiser 4.3L/V6 engine specifications including horsepower, displacement, rpm, oil pressure, ignition timing, firing order, etc. |
Mercruiser 4.3L Engine Spec’s | Mercruiser 4.3 V6 engine mechanical specifications including fastener torques, and engine manufacturing dimensions and tolerances. |
Mercruiser V6/V8 Fastener Torque Spec’s | Mercruiser V6 & Small V8 fastener torque specifications. |
Mercruiser 5.0L Performance Spec’s | Mercruiser 5.0L/V8 engine specifications including horsepower, displacement, rpm, oil pressure, ignition timing, firing order, etc |
Mercruiser 5.7L Performance Spec’s | Mercruiser 5.7L/V8 engine specifications including horsepower, displacement, rpm, oil pressure, ignition timing, firing order, etc |
Mercruiser Vortec 5.7L Engine Spec’s | Mercruiser 5.7L V8 engine mechanical specifications including fastener torques, and engine manufacturing dimensions and tolerances. |
Mercruiser Alpha Sterndrive Specifications | Mercruiser Alpha Generation 2 Sterndrive Product Specifications |
Mercruiser Bravo 1 Sterndrive Specifications | Mercruiser Bravo 1 Sterndrive Product Specifications |
Mercruiser Bravo 1X Sterndrive Specifications | Mercruiser Bravo 1X Sterndrive Product Specifications |
Mercruiser Bravo 1XR Sterndrive Specifications | Mercruiser Bravo 1XR Sterndrive Product Specifications |
Mercruiser Bravo 2 Sterndrive Specifications | Mercruiser Bravo 2 Sterndrive Product Specifications |
Mercruiser Bravo 2X Sterndrive Specifications | Mercruiser Bravo 2X Sterndrive Product Specifications |
Mercruiser Bravo 3 Sterndrive Specifications | Mercruiser Bravo 3 Sterndrive Product Specifications |
Mercruiser Bravo 3X Sterndrive Specifications | Mercruiser Bravo 3X Sterndrive Product Specifications |
Mercruiser 7.4L Performance Spec’s | Mercruiser 454 engine specifications including horsepower, displacement, rpm, oil pressure, ignition timing, firing order, etc |
Mercruiser 8.2L Performance Spec’s | Mercruiser 502 engine specifications including horsepower, displacement, rpm, oil pressure, ignition timing, firing order, etc. |
Mercruiser Big V8 Engine Spec’s | Mercruiser 7/4/8.2L Big V8 engine mechanical specifications including fastener torques, and engine manufacturing dimensions and tolerances. |
Mercruiser Big V8 Fastener Torque | Mercruiser Big V8 Engine Fasteners Torque Specifications. |
Mercruiser 8.1L Performance Spec’s | Mercruiser 8.1L/V8 engine specifications including horsepower, displacement, rpm, oil pressure, ignition timing, firing order, etc |
Mercruiser 8.1L Fluid Capacities | Mercruiser 496/8.1L marine engine fluid capacities. |
Mercruiser Alpha Transom Details | Mercruiser Alpha Transom Assembly specifications and details. |
Mercruiser Bravo Transom Details | Mercruiser Bravo Transom assembly specifications and details. |
Mercruiser Battery Cable Requirements | Mercruiser Battery and Cable Sizing Requirements. |
Mercruiser Combustion Air Requirements | Mercruiser Combustion Air Requirements. |
Mercruiser Engine Harness Schematic | Mercruiser Engine Wiring Harness Schematic. |
Mercruiser Exhaust Resonators | Mercruiser Exhaust Resonators & Water Ingestion. |
Mercruiser Fuel Requirements | Mercruiser fuel and octane requirements and ethanol recommendations. |
Mercruiser Gasoline Requirements | Gasoline Recommendation For Mercruiser Marine Engine Models. |
Mercruiser Oil Specifications | Mercruiser marine engine oil technical specifications. |
Mercruiser Engine Oil Capacities | Use this quick link to find your Mercruiser engine oil capacities. |
Mercruiser Sterndrives Gear Lube Capacity | Use this quick link to find your Mercruiser Sterndrives gear lube capacities. |
Mercruiser Power Trim Wiring Diagram | Mercruiser Power Trim System Wiring Diagram |
Mercruiser Mercathode Wiring | Mercruiser Mercathode System Wiring Diagram |
Marine Engines Spark Plugs | Marine Engines Spark Plug Conditions |
Mercruiser Engine Timing Procedures | Mercruiser Engine Timing Setting Procedures |
Our Mercury Mercruiser Technical Product Specifications Library features a wealth of Mercury Outboard Parts information for novice and veteran boating enthusiasts, including easy-to-follow how-to videos and valuable articles. Search for the information you need by category, whether you’re looking for articles on Quicksilver Marine Longblock’s or Mercuiser Sterndrives. You will also find a listing of technical articles covering important boating topics such engine ooil capacity, intake manifold fastener torque on models such as the Mercruiser 454 and 3.7L engines. We also have several articles covering the ever-important topic of Propeller Fundamentals. And if you still can’t find the information you need on this page, please don’t hesitate to contact us via phone or email. Our experienced and friendly staff is always available to answer your questions and guide you down the right path. Also keep in mind that we are Authorized dealers for both Suzuki Outboards as well as Yamaha Outboards as well, so if you need assistance with those models be aware that we do have certified Yamaha and Suzuki technicians on hand.
BACKGROUND: Performance Product Technologies offers more than 25 years of technical experience and knowledge in the boating and marine parts industry. We understand the design and engineering of everything from long block engines to the basic marine accessories such as Marine Starters & Alternators. This wealth of industry specific knowledge makes us a reliable source for insight and advice on the best parts and options for your boat and/or marine engine. Therefore whether you would like to buy a specific Mercury part and need help ordering from the online diagrams in the Mercury Marine Parts Catalog or you just need advice on how to select the proper Closed Cooling System, you will find it here at PPT. We have the most complete Technical Specifications library on the internet. This library contains guidelines and specifications for both Engines and Sterndrives. The key to locating the correct technical information for your particular engine or sterndrive starts with the Serial Number. You can follow this LINK for a guide on locating your Serial Number. If you have trouble locating the correct information for your Motor or Outdrive feel free to email us at [email protected] for further technical assistance.
Tags:fuel requirements, mercruiser, mercury marine, oil pressure, technical specifications, temperature, torque specifications, wiring diagrams
Posted in Technical Articles, Technical Specifications | No Comments »
Warm versus cold marine exhaust manifolds refers to the temperature of the cooling water that is introduced into the exhaust manifolds on a marine cooling system. This specific system feature can apply to raw water (also known as open cooling) systems as well as Fresh Water (also known as closed cooling) systems. For the purpose of this article we will be primarily detailing the raw water cooling systems. To read more about 1/2 versus full closed cooling systems, select this link.
The standard raw water cooling system operates via a pressure balance. The easiest way to think about these systems is that you have a circuit of coolant being circulated through the engine via the engine circulating pump. There is also a supply pump that introduces cooling water into this circulation loop, depending on the position of the thermostat and amount of coolant being allowed to exit the system. For example the circulating pump on a standard small V8 GM based engine will flow approximately 50 gpm through the engine. The typical raw water supply pump inside the Alpha sterndrive is capable of flowing about 18 – 20 gpm depending on the gear ratio and restriction the system experiences. A standard 300 Hp small V8 engine dissipates approximately 300,000 Btu/Hr of heat into the coolant. To maintain a thermostat temperature of 160 degree F at wide open throttle this engine would need a pump to flow about 8 gallons per minute (GPM) of 70 degree F water into the system to maintain this engine temperature. Since the Alpha raw water pump can flow 18-20 GPM there is significant bypass (excess) water supplied, which therefore has to be dis-charged somewhere.
In a cold manifold system the warm water that flows through the thermostat, as well as this excess bypass water are joined together in the thermostat before exiting and being introduced into the bottom of the exhaust manifold. The fact that your are mixing together a lesser amount of 160 degree F engine water (8 GPM) with 10+ GPM of cold lake water allows the aggregate coolant temperature in the manifold to fall below the 110 degree F threshold needed to prevent the accumulation of condensation in the exhaust system. Notice in the picture below that there are only (4) hose bibs as these systems are typically identified by this fact.
In a warm manifold system the warm water coming out of the engine and through the thermostat is the only coolant that actually passes through the exhaust manifolds before passing through the manifold riser gasket joint and mixing with the cold bypass water that is being introduced into the riser. The fact that your mixing point for the coolant is above the manifolds allows the temperature to be maintained above 110 degrees F and therefore prevents the accumulation of condensation in the exhaust system. Notice in the picture below that there are (6) hose bibs as these systems are typically identified by this fact. NOTE: The thermostat cover is not shown but actually contains the additional (2) hose bibs.
WARM MANIFOLD SYSTEM
Tags:cold manifolds, marine exhaust manifolds, marine exhaust systems, warm manifolds
Posted in Alphabetical List of Articles, Technical Articles | No Comments »