Outboard ventilation symptoms
Outboard ventilation symptoms. What is unusual is the idea one motor is leaking (bubbling) more than the other. The ignition switch sends a signal to the solenoid when you turn your key allowing it to open; this allows voltage from your battery to pass through it to the starter motor. Apr 21, 2009 · tcarpe1. A thorough diagnosis by a qualified marine technician is always recommended for confirmation and proper repair. Make sure to pinpoint the correct vent hose location for your setup and there’s no presence of the said sags. You may notice that your car is sluggish when you press the Jun 14, 2016 · Older fuel hose has an engineered maximum permeability rate of either 100 or 300 grams per square meter for a 24-hour time span. Sometimes, the hub only spins when the engine revs above a certain RPM, causing many boaters to wonder if they have spun a hub, are experiencing ventilation or cavitation, or have some kind of gear or power issue with their outboard. this occurs when the crankcase oil becomes contaminated with fuel. #5. Jun 3, 2023 · Hard Starting and Idling Issues. When the vent is blocked, it creates a vacuum in the fuel tank, making it difficult for the pump to draw fuel. The FSM has different electric fuel pumps, float switches, and Jan 11, 2021 · Jan 11, 2021. With the engine trimmed down, prop seems to cavitate or ventilate when powered up and boat attempts to plane out. Depending on the age of your unit, there is a good chance that you’re dealing with a broken propeller that needs to be fixed. If oil or similar fluids are dripping from your outboard motor, you most likely have a blown lower unit. If your boat is having trouble starting, it could be due to a defective ignition sensor. Engine Misfires: The engine stutters, coughs, and hiccups like a dragon with indigestion. When the outboard motor is mounted too high, it can cause the water intake to draw in air instead of water. You may see a “rooster tail” of water behind the boat, which is caused by air being drawn into the propeller. Electrical or tilt/trim motor issues. Re: What are the symptoms of a bad coil? A bad coil can go in and out and cause power surges when you get spark on the dead cylinder. This could present itself in various ways, such as hard starts, stalling out after starting, or difficulties turning the engine over. Rough Idle: A bad reed valve can lead to an erratic or rough idle. This leads to a sudden reduction of water load on the blades, an 1. #2. In this case the spark plug could be wet, which is an indication of water in in the combustion chamber. Apr 19, 2014 · Messages. Flywheel. Fuel Primer Feels Soft: If your outboard has a fuel primer bulb, it may feel soft or spongy after squeezing, indicating air in the line. When it is trimmed all the way down, the bottom of the anti-ventilation plate should be about 1" above the keel per feet distance to the transom. 7. – Rough Edges. Sluggish Starts and Battery Woes: If your engine Oct 28, 2019 · Through-hull fuel vents are designed for installation on a vertical (or slightly angled) exterior hull surface so that fumes vent outboard and not inside the boat. Mar 28, 2023 · The most common signs of a bad stator in a Mercury outboard engine are problems with engine activation, lack of power, and misfiring. Visible Bubbles in the Fuel Line: In a clear fuel line, you might see tiny air bubbles moving through the fuel, indicating an air leak. Boat ventilation is provided by strategically placed ports, hatches, cowls, clamshell vents, or a combination of the types. . Turn off the main electrical cutoff switch. Any owner seeking the last bit of speed from an outboard-powered boat, whether it has a big new Yamaha F350 or a diminutive Suzuki DF25, should grab a yard stick. New prop is a OMC 11-1/2x19, old prop was a OMC 11-3/4x17, both cupped aluminum. Rough Idle and Uneven Performance: A failing trigger Sep 23, 2003 · 79. The coils of some mercury outboards are sealed inside a unit with oil. Remember: While these symptoms can point towards a bad coil, they can also be caused by other issues like faulty spark plugs or fuel delivery problems. You may notice black smoke or a strong smell of unburned fuel. 6. the grinding/vibration is generally more Remember: While these symptoms can point towards a bad coil, they can also be caused by other issues like faulty spark plugs or fuel delivery problems. It is specifically avoided in the correct design of props and that is why prop fabrication and prop repair must be relegated to the experts. This lack of fuel can cause the engine to run lean, leading to a lack of power and slow acceleration. Oct 23, 2010 · takes 10-15 seconds to use the diagnostic test lamp to check for any sensor codes. Make sure engine is adjusted to proper height when sitting in the water. Turn your needle valve clockwise until it seats (lightly) and then back it out in 1/8th increments until the Jul 23, 2022 · Symptom 4: Less Sound While Igniting the Motor. The clamp bracket on the latest Mercury Four-Stoke-model outboards has five mounting bolt holes spaced . Now, to use a venting gas tank with outboard motors, kindly follow the guide below. A bad trigger disrupts the precise timing of the spark, leading to incomplete combustion and erratic engine behavior. Jul 19, 2009. Jul 23, 2022 · Bad or damaged propellerMisfiring in cylinders. Outboard motor. An unblocked will emit a gurgling sound. Force grease into the grease fittings on the front of the swivel bracket. Anyway, you will hear/feel a vibration & associated noise when you turn or have the outdrive at high trim angles. Plus, if the battery fails to charge continuously and corrosion build-up around the stator’s surface, rest assured that the stator will become faulty! Getting panic attacks? Feb 25, 2022 · During the sea trial of this Remanufactured 175HP Evinrude Tim, owner of Outboard Exchange in Waterford, CT, realizes the outboard is mounted too low. As well as providing propulsion, outboards provide Feb 17, 2022 · Some are automatically opened when they detect pressure from the fuel tank. If you notice that your boat is not moving as quickly as it normally does, it may be because of cavitation. You may hear a popping or hissing noise coming from the boat. Based on many reports of problems with the oil lubricating sump being contaminated with gasoline in marine four-cycle outboards, and your narrative of the symptoms, I'd say your Yamaha motor has this problem. Put the carb back on the engine and started it, and everything seemed to work great. I was putting gas in the boat today. A crack on that unit is also a sign of a bad coil. It was at little less than 1/4 tank. By following these simple tips, you can improve your boat’s prop ventilation and keep it from taking on water. This noise is caused by the bubbles forming and collapsing. 1. Looking for a solution that isn't a $1,000 jack plate! Thanks for the help! Winterization: Properly winterize your outboard to prevent moisture buildup and corrosion that can harm the stator. Jul 23, 2022 · The common symptoms of water in a boat’s gas tank include engine misfiring, hard starting, stalling, or reduced performance. Apr 19, 2014. Engine Backfiring and Misfires. Your motor appears several inches too low and tucked too Jun 27, 2010 · The beginning of the season I had to pump 6 gallons of watered down gas out of my tank before being able to get it clean enough to run. If you have questions about cavitation or ventilation or need help with your propeller installation, contact us here or call the experts at Ace Propeller at 1-866-621-7767. Non-Weldable or Full Skeg Repair: $400-$500. Difficulty Starting the Engine. Take the canister vent line off the gas tank and blow through it. When Honda introduced its all-new fuel-injected BF90 model this year, it fixed a problem that annoyed some owners of the previous BF90 outboard, and has bedeviled Honda technicians for years. During an exhaust system inspection check hoses for leaks, kinks, chafe, bulging (at hose clamps), cracks and other signs of deterioration. This equipment is used to exhaust stale air out of boat cabins, engine compartments, and enclosed spaces, and to force fresh air through the vessel. Mar 29, 2022 · Cavitation and ventilation of a propeller (except in certain special cases) have a negative impact on the performance of a boat. Feb 19, 2010 · Re: symptoms of a clogged carb. Cause. Aug 29, 2020. Under normal conditions, water boils at Aug 19, 2010 · Aug 19, 2010. Raising an outboard higher on the transom can reduce drag and raise top speed. Remove the snaps on the outboard motor upper case and take off the cowl cover. That should do it. With your socket wrench, remove the plug. There is a $25 fee for all on the boat skeg repairs. The needle valve should get you a happy medium at about a quarter turn counterclockwise from where the motor will sneeze. Engine Misfires and Sputtering: This is the most common symptom. The nozzle shuts down, and gas leakage makes refueling hard and leads to risks of over-pressurization. A good tech should have one. 4) One or more plugs show a lean condition (a reason to check them often). A blocked line will result in no sound. In fact, most manufacturers still do. Stalling or Rough Running. Comes out of the water good and hits top end w/out any problems. He described his boat as a 1994 16-foot center console with a 1994-model 70-horsepower engine. Use a small brush or compressed air to gently clear away any debris, insects, or dirt from the vent cover. rebuilt carbs, fuel pump and new fuel lines all the way to the tank; and the boat is running much better. It needs the right prop, and such things as engine water pressure and temperature have to be closely monitored. the grinding/vibration is generally more Cavitation Plates: $300-$400. This can lead to cavitation, which causes the propeller to lose its grip on the water and spin freely. The anti-vent plate should be level, or slightly higher than the keel. So, if the optical sensor goes bad, it will fail to send the signal, resulting in intermittent or Jul 23, 2022 · Symptom 1: Engine Having a Hard Time Starting. Every spot, every tow, every cast. Turn off the engine and all ignition sources immediately to avoid sparks near fuel vapors. This adjustment is provided to let the boat builder or owner fine-tune the mounting height. Feb 18, 2022 · Replace this exhaust hose new before these cracks get bigger and go all the way through. Oct 6, 2016 · gonzo said: ↑. May 24, 2009. Outboard Engine Stalling or Cutting Out. 75 inches apart. Backfiring: Loud pops and bangs erupt from the exhaust, a sign of improper timing caused by a malfunctioning trigger. Inconsistent Spark or Weak Ignition. It's not unusual to see exhaust leaking there with the boat idling out of gear/boat not moving. May 28, 2013 · Re: Sumptoms of bad ujoint and gimble and coupler. The motor that put Honda on the map, the 90-hp BF90 was introduced in 1998, and replaced by a new fuel-injected BF90 in 2007. An outboard motor is a propulsion system for boats, consisting of a self-contained unit that includes engine, gearbox and propeller or jet drive, designed to be affixed to the outside of the transom. Various seals and gaskets keep these oils confined to where they are needed. The problem has been intermittant and it doesn't show the same exact symptoms every time out. You may notice that the engine RPMs are higher than normal, but the boat is not moving any faster. It can just lack power totally because one cylinder is dead from no spark. This typically refers to all hose leaving your fuel tank and ultimately going to your engine. – Some Missing Material. Lower unit turns bad. Sep 14, 2023 · Symptoms of an outboard mounted too low include poor handling, excessive drag, ventilation (air being sucked into the propeller), and reduced top speed. Jul 20, 2013 · Re: Symptoms of a Bad spark plug wire. Nov 10, 2023 · Symptom 4: Cavitation. May 2, 2023 · A blocked fuel tank vent can cause slow acceleration and a lack of power. Symptoms that point to carb issues are sometimes subtle and sometimes very obvious. A weak spark from failing plugs can leave you stuck at the dock, yearning for open water. Also in corners prop breaks loose easier than the old prop. Cavitation occurs when there is an extreme reduction in pressure on the back side of the propeller blades. DO NOT run above 4000 RPM with a defective or unplugged O2 sensor. New boat . Experiencing Operator Shifting Trouble. But here are a few: 1) Poor idle quality. I have a really good mechanic who does my work for me, but when the problem first surfaced I immediately checked all the obvious stuff related to gas. Shoot some air into it. Misfires often point to inconsistent or weak spark caused by worn-out plugs. While you can raise a 20" motor on a 15" transom by building a riser or jackplate, it's generally not advisable to cut down a 20" transom to accommodate a 15" motor. I'm having a problem with my 1990 Evinrude 70hp losing power while on plane. Other symptoms may include fouling spark plugs and an irregular idle. * Exact pricing will be determined at drop off when the damage can be evaluated. Nov 15, 2022 · Suzuki 90 HP Outboard Problems. 2) Poor transition from idle to midrange rpm. One of the most noticeable signs of a faulty ignition coil is difficulty starting the outboard engine. Messages. All the shafts and the gearbox use oil and lubricants for smooth movement. A crankcase ventilation system ( CVS) removes unwanted gases from the crankcase of an internal combustion engine. With innovative technologies, simple maintenance and efficient performance, Mercury FourStroke Jun 5, 2012 · If your motor is running lean, it will "sneeze" at low rpm, if it's running rich it will smoke and foul the plugs. Take the spark plug wire boot off the plug tip. 5) Lack of high end power. Your local Mercury Authorized Dealer is the best place to see and purchase Mercury engines, parts and accessories, and to get expert support when you need it. This could be caused by the ignition timing being off, impacting the engine’s combustion process, and leading to difficulty in starting the engine or maintaining a stable idle. This can result in a rough and erratic running engine. Solution. As a boat owner, it’s vital to look for any signs of water in the gas tank. Regularly monitor your engine’s performance and seek professional assistance if stalling becomes a recurring issue. If your Johnson Outboard engine suddenly shuts off while underway or at idle, it may be a sign that the power pack is failing. Ventilation is the result of the entrance of air or exhaust gases (they are drawn into propeller blades) between and around the propeller blades. Verify each hose is double clamped where possible (i. "What would be the symptoms of a bad carb float? I ordered a new float chamber and cleaned the carb up real good. The most common name or older name is VST. Noise and vibration issues are first on the list when it comes to Suzuki 90 HP outboard problems. Symptoms: Your outboard engine may stall or run roughly, with erratic idling or acceleration. The type of ventilation depends on boat type, deck layout, and cabin size Sep 23, 2003 · 79. making oil. Locate the external vent cover on the boat’s hull and inspect it for visible blockages. Sep 23, 2003. In other outboards, coils are inside a unit without oil. over propping will do the same. It will start, idle up, and then bogged down. You can often tell that an outboard is too low if you are experiencing sluggish speeds, poor handling, excessive spray, porpoising, or even water pushing up into the cowling. Prop looks next to new with no apparent damage. This is the most common symptom of a bad optical sensor on a Johnson outboard engine. What does it mean when your motor is cavitating? Cavitation occurs when a boat and outboard are not setup properly. Because of another component failure. e. no codes no worries. Engine Performance: Loss of Power: This is one of the most noticeable symptoms. So chances are I pumped a lot of contaminated gas through my filter. May 4, 2012 · Ask the experts on our Yamaha Outboard Forum for repair issues, diagnosing problems, links to diagrams, suggestions on buying parts and more. However, there would be comparatively lower sound with this if the fuel pump is faulty. Addressing the original question, a damaged piston may be detectable before head removal by using a borescope to inspect the inside of the combustion chamber. They are the most common motorised method of propelling small watercraft. Another symptom is noise. Step 1. To further diagnose the problem, follow these steps. Jul 23, 2022 · Symptom 3: A leaking Unit. Aug 31, 2022 · Clogged Vent. Excessive Smoke. If that doesn't work, I'll likely invest in a pair of trim tabs. sufficient hose barb to allow it) and that hose clamps are Oct 3, 2006 · Oct 2, 2006. Overheating: Insufficient airflow due to a malfunctioning reed valve can lead to engine overheating. Loss of Power: Your once-mighty steed feels sluggish, struggling to maintain RPMs and Mar 28, 2023 · Symptom 1: Leakage of Oil or Cracks on the Body. The unwanted gases, called "blow-by", are gases from the combustion chamber which have leaked past the piston rings. You may experience sluggish acceleration and difficulty reaching top speeds. If you find any oil on that unit’s body, it means it surely has a crack on it. Fuel Pump May Turn Bad. OR, it can run fine, then when the motor warms up and thermal expansion causes you coil to go out, then lose power. If the engine cooling system is not properly controlling Jul 23, 2022 · Symptom 4: Less Sound While Igniting the Motor. The prop is an aluminum 17 pitch Mercury Black Max (recommended by Merc). Feb 2, 2024 · The spacing between the upper holes is 0. They can answer questions for any Yamaha outboard model or horsepower. Re: mercury leaking 2 stroke oil. I think I'm getting some slipping from ventilation at full trim out. Sluggish Starts and Battery Woes: If your engine Aug 27, 2022 · One symptom of cavitation is a decrease in speed. I replaced the gasget for the on motor reservoir cap, but its still doing it, so I think I got it traced back to the vent tube. – Bends. Nov 11, 2022 · 6. Weldable Skeg Repair: $300-$400. If I understand correctly, you replaced the cap gasket but, the oil wasn't actually coming out from Misfires often point to a faulty trigger signal. Mar 28, 2023 · Symptom 1: No Spark. Jul 11, 2022 · 28K views 1 year ago GREEN LAKE. An outboard motor with timing issues might be hard to start or have a rough idle. Yes it looks too high. #3. 19 pitch yields 5500 rpm with average load so I think Aug 29, 2020 · Bismarck. Smoke and Fumes: A bad reed valve can cause excessive smoke and fumes from the boat’s exhaust. Another symptom of a bad outboard spark plug is the engine stalling, sputtering or cutting off. Jul 18, 2009 · Jul 24, 2005. Jul 2, 2007 · From what you posted, here are the 2 actions I'm planning on taking: 1. a stuck t-stat will cause an over rich fuel mix and can push excess fuel past the rings. Wrong installation of vent line or breather hose, trapping fuel due to the presence of sags. +1. If that’s not the issue, it’s best to consult a boat motor repair specialist to diagnose and fix the problem. Try washing the spark plug with soap and water, drying it off and plugging it back in to see if that May 3, 2022 · A spun hub feels like a loss of power with excessive RPM. The 100-gram standard applies to fuel hose installed in the distribution side of your fuel system. A weak or inconsistent spark can lead to power loss. Next, listen for the solenoid/start relay (Photo 1) while operating the helm control (tilt) switch up or down. Feb 27, 2024 · This is effectively a gate. Merc's are notorious for wiring going bad, cracking and corroding. These vents help overcome the sucked pressure from the fuel pump to the motor. Sep 1, 2009 · In a recent e-mail, a reader requested help with what he believes is a cavitation problem. POWER TILT TRIM Temporary “Down” Lockup. amosh said: my v-200 1991 mercury is leaking oil. Prop breaks loose and motor revs up a bit with my new prop. May 24, 2009 · 3,903. This results in reduced performance, including slower acceleration and top speeds. Check ALL your ignition wires actually ALL your wires. A surfacing setup is extremely sensitive to prop damage. The optical sensor in an outboard engine sends a signal to the switch box or power pack to release a spark or voltage to the ignition coil. If you find yourself repeatedly pulling the starter cord or engaging the starter motor without success, it’s time to consider the ignition system as a potential source of the problem. Jul 7, 2018 · Looking for help determining the root cause for my ventilation issue. Make sure that you are using the correct size and type of propeller for your boat. What is curious is when I'm cruising along (regardless of rpm) the engine occassionly "kicks in" a May 22, 2019 · The cure is to loosen one of the large tilt/steering nuts 1/2 turn, then with a 2×4 and a large hammer force the swivel bracket sideways slightly. What happens is the prop is too close to the Nov 11, 2022 · Here are some symptoms to look out for that may indicate a problem with your boat’s prop ventilation. Unusual smoke emissions from the outboard motor’s exhaust can indicate underlying issues: Solution: Blue smoke often indicates oil leakage into the combustion chamber, while black smoke suggests a rich fuel mixture. #4. 902. If you're turning your key and the starter motor isn't cranking then you may have a faulty solenoid. An outboard that is mounted too low will limit your boat’s optimal operation. Has the boat been out of the water long enough for there to be a big wasp nest forward of Jul 23, 2022 · Symptom 1: Trouble Starting. Jun 19, 2007 · June 19, 2007. Use a straightedge on the bottom for alignment. Re: Yamaha 4-stroke, fuel in oil. However, it is common to hear people claim, incorrectly, that the engine “cavitates”. Rough Idle and Uneven Performance: The engine may struggle to maintain a steady RPM Table of Contents show. 1977 Evinrude 70hp #70773S. Does your outboard motor have a "ventilation" or "cavitation" problem? When an outboard motor loses its water intake and begins to blow air, it is said to be "venting". At low speeds the boat is running like crap and has power surges at low rpms. The boat is a 79 Laser Bass (pictured) and the prop is a SS 13 3/4 19P w/no damage or dings. In some cases boat performance can be improved by mounting the outboard at a higher Symptoms of an Outboard Mounted Too Low – The Short Answer. He explains how to tell and how it affects Dec 4, 2023 · The Engine Stumbles and Sputters: A failing sensor disrupts the precise timing of the spark, leading to incomplete combustion and erratic engine behavior. Yet this also creates one of the biggest problems with vents: the tendency to let water in. Try washing the spark plug with soap and water, drying it off and plugging it back in to see if that May 8, 2008 · Setup is critical. When I started pumping the gas started coming back out of the fill hole. Other outboards have manually operated ventilation. Position yourself near the tank before filling it. 75 inch. 3. Even if I tried to go slow it would start coming back out of the fill hole and the hose. Make sure there is adequate clearance between the bottom of the boat and the propeller. When Mercury Marine came out with the Verado engine, they changed the name to Fuel Supply Module. If you try to raise or lower the engine and nothing happens, first check that your battery is fully charged and that the battery switch is in the “on” position. Recreational Outboards - Make every minute count. Sep 1, 2009 · Cavitation is often confused with ventilation. Mar 23, 2014 · Re: Anti-Ventilation plate on older motors. You’ll experience frustrating misfires, sputtering, and coughing, especially at low speeds or under load. #1. As a result, when the primer malfunctions, it cannot provide the spark and pressure Why the Two Names. Problem. I did not run the gas out of the engine, and today the engine is doing the same thing it was. There is no chance of any leakages. Dim lights, flickering gauges, and erratic electronics are a prime indicator of low or inconsistent voltage, a potential symptom of a bad rectifier. The first and most common symptom you will see when the primer solenoid goes bad is the engine’s difficulty starting. CHAPTER 6. The current ventilation systems on both 110 and 210 foot cutters are not adequate to provide effective protection in the case of a CBR attack or provide effective filtration of indoor air contaminants. Not to measure boat speed, but to gauge the Here are some prominent symptoms to watch out for: Dimming Lights and Flickering Electronics: Imagine the stage lights dimming mid-performance. I had checked the fuel tank vent before by blowing in it and it did not seem clogged. Re: symptoms--leaking air. Your wires "screw"into the connectors and those ends do go bad. Here are some prominent symptoms to watch out for: Dimming Lights and Flickering Electronics: Imagine the stage lights dimming mid-performance. One of the most common symptoms of a bad ignition sensor on a Mercruiser is trouble starting. You will likely feel the prop slipping at high RPM. Try to adjust the anti-ventilation plate by loosening bolts and turning plate in direction of lean/pull. This is due to the lack of an advanced filtration system and significant building envelope leakage. Learning the reasons can help maintain your boat and prevent damage, so Jul 23, 2007 · Jul 24, 2007. A damaged reed valve can cause a significant drop in power, especially at lower RPMs. The sound of the motor would be as low as soothing music in case you want an example. Trouble In Getting The Outboard On A Plane: Some of the Yamaha VMAX SHO users has mentioned their struggle to get their outboard on a plane. 19 pitch yields 5500 rpm with average load so I think Jun 19, 2008 · Re: Bad Piston- Symptoms. 5. We all know the usual sound of the Mercury outboard motor when we ignite this. Also you may see very tiny bits of aluminum splattered on the spark plug electrode. You're right in that the anode area is open to the exhaust. Feb 2, 2024 · Boost Speed with Outboard Engine Height Adjustments. a ruptured fuel pump diaphragm can dump raw gas directly into the crankcase. The power pack plays a crucial role in generating spark for Sep 12, 2023 · Start by inspecting the water intake to ensure it’s clear of debris. Inspect the oil levels and the oil injection system (if equipped) for leaks. 2,169. My plans are to change the filter and dump in some seafoam. When the primer gets bad, it cannot push fuel into the engine, so it cannot start normally. May 3, 2022 · A spun hub feels like a loss of power with excessive RPM. 4. 3) Hard starting. Don’t Ignore Warning Signs: If you notice any of the symptoms mentioned above, don’t delay! Address the issue promptly to avoid further damage and costly repairs. it should not have any symptoms of bad u-joints, etc. Move this wire around from the opening by taping it to another part or wedging it between components. How do you tell if a boat is over propped? Signs of an overpropped boat include difficulty reaching the engine’s recommended RPM range at wide-open throttle, slow acceleration, and decreased Jan 22, 2024 · First, you find the air vent line and put a compressor into it. That is the first rough approximation. Almost all Outboard engine manufacturers at some point in time called this the VST. Gimbal bearings can make a variety of noises if they are going bad. Loss of Power: Your trusty steed feels sluggish, struggling to maintain RPMs and accelerate. the O2 sensor has NO codes unplug it and fuel is fixed rich at low speeds and lean above 4000 RPM. Son recently purchased a 2014 Tracker Pro-Guide V-175 with a 115 HP Merc four stroke. How do you tell if a boat is over propped? Signs of an overpropped boat include difficulty reaching the engine’s recommended RPM range at wide-open throttle, slow acceleration, and decreased May 4, 2012 · outboards, so far, do not use a positive crankcase vent system. You can then tinker with it a bit up or down. The system usually consists of a tube, a one-way valve and a vacuum source (such as the inlet manifold ). 2. Excessive Noise. dc xl oq cm qy hg de ho gh um