This is an infrared thermometer and it is what I consider to be an important tool for any boat owner. Page 1 ... turbo64 Light Load Member. We look at diagnosing diesel engine problems and how to repair two common marine diesel engine issues. Jul 25, 2014 0. The number of hours that a marine engine runs is very dependent on the amount and quality of maintenance over the years. DaveDMCMW is spot on. Since this is an open forum, not all views expressed by its participants are shared by the owners and moderators of the forum. Solution is to snake with a wire and dip in … This can cause it to overheat. As soon as they back off the load, then the temperature drops. Also, as I haven't been burping with the coolant cap off, I will try that. For instance, diesels should turn at maximum-rated rpm under load without the governor kicking in and without belching smoke. Spark Plug Wires & Ignition: Spark plugs are what help your engine produce power in the first place. Second check for flow into the bottle from the rear of the engine for blocked T. Now to bleed a pesky air pocket out of your car, this method works every time and uses a little science. I can restart the engine but it dies in a few minutes. A surprisingly common and easily overlooked one is failing to open the cooling water seacock after working on the engine.It’s important to understand the elements of the cooling system on your boat – two different types are commonly fitted to marine diesel engines. This may be the case if no other problems can be identified – if so after allowing the motor to cool it may be possible to continue at modest speed without further problems. Most owners don't realize this and we probably wouldn't have either if Tony Athens at boatdiesel.com hadn't recommended that we ensure the engine could spin up, under load, to MORE than the rated RPM. Often people put on extra large props for fuel economy. Enjoy the forum everyone! The truck can idle for 5 hours and just start getting heat to it, bobtailing it does not over heat but as soon as it gets hooked to a trailer I starts to overheat. The average marine gasoline engine runs for 1,500 hours before needing a major overhaul. Test if in neutral aka “no load,” she can come up to speed. Then (in a DeLorean) jack up the "rear" of the car as high as you can and start it. No doubt. At this point it's best to get all of the air out NOW and not wait for it to work itself out. The typical pattern is that their engines run hot under load (eg towing a trailer, going up a range, higher cruising speeds), rather than idling in traffic. If the diesel engine is not charging batteries the warning lamp will light, but with many engines the alarm buzzer will not sound. Although many people replace their marine thermostat with automotive replacements, in many cases they are subjecting their engine to conditions which will cause long term damage. A little investigation & prevention can save you a lot of time and money. That being said, I have done so many times in the past few days. Trucking Jobs in 30 seconds. By that time he will have blown his head gaskets. Some examples of what may occur due to overloading a marine diesel engine include: Excessive Black Smoke; Slow Acceleration; Excessive Fuel Consumption; Overheating; Reduced Engine Service Life and Component Failure Throughout the Exhaust Gas Flow Path (e.g., valves, pistons, rings, liners, turbochargers, and exhaust manifolds). www.framingjohndeloreanfilm.com. Cummins ISX Still Overheating Discussion in 'Trucks [ Eighteen Wheelers ]' started by Working Class Patriot, Jul 26, 2014. Propeller pitch or diameter, damaged blades 3. As the weight increases and the bottom becomes less than perfect, the engines end up working too hard. Registration is free, and by doing so you get to post and participate in the discussion and view any attachments. Overcooling can damage an engine as much as overheating because the parts don’t expand properly, and the engine is allowed to run under any load at substandard temperatures. Most marine FWC thermostats open at 160°F and will be fully open at approximately 180°F. Start the engine and run it for 30 seconds. turbo64, Jul 26, 2014. turbo64, Jul 26, 2014 #10 + Quote Reply. He currently sails around 5,000 miles per year and in the past couple of seasons has cruised from the UK to the Azores, as well as winning his class in the 2014 two-handed Round Britain and Ireland Race. The injectors, fuel filter and low pressure fuel pump have all been replaced. The point here is that air is trapped and it's already overheating under load. Test this by letting the engine warm up, then running the engine at full throttle while in neutral. 5 Common Causes of Low Diesel Engine RPMs Posted on October 7, 2010 December 14, ... problem is too large a prop. Copyright © 1999-2021 Boats Group. As I always say “tools are free“.What I mean by this is the expense of the tool, and doing the job yourself, is almost always paid for by the labor savings.In 35 years of tool buying I have yet to find one that was not paid off in one or two projects or uses. Usually really weird overheat issues are head gaskets on the way out. Using a pressure tester just introduces more air and creates pockets between the engine rear and the heater core ( hence running the heat at full to cool the engine), DMCTalk F.A.Q. 4.3 MerCruiser Overheating (4.3L MPI Alpha and Bravo) 2001-2008. I will attempt to bleed again from both ends. Any left after that will work it's way out. I have a 2006 international 9400i with a Cummins ISM. He also owns two yachts, one based in the Mediterranean and the other in the UK. Any temperature that reads outside of this range is abnormal and should be investigated. At this point it's best to get all of the air out NOW and not wait for it to work itself out. So, here is an article I did on how to trouble shoot an overheating engine with a … When under load for 20 minutes the rpm drops, a small amount of white smoke comes out of the exhaust and the engine dies. check out the. I promise this is your fix. That problem is typically accompanied by expelling coolant from the cap. This can be a result of engine components, such as the cylinder head, expanding due to excess heat. White smoke from a marine diesel engine is one of the most difficult symptoms to diagnose because a number of factors can point to two general causes: overcooling, whereby the cylinder head and combustion chambers operate at a temperature that’s too low for proper combustion; and piston-ring blowby, which indicates low compression and poor combustion. boats.com, Cams Hall, Cams Hill, Fareham, Hampshire, PO16 8AB, UK. Maintenance. Re: 454 overheats under load hi maclin , thanks for your interest and following my threads !!! We often get the question, ‘why is my 4.3L MPI MerCruiser overheating?’. See why changing your filters, fluids, and warming your engine up can add to a … If the voltage is less than 13V, the battery is probably not being charged. The water pump impeller on a marine diesel engine is easily damaged. How much it is shortened will depend on the degree of severity of the over or under sizing. I got engines overheating 4 times, here is the story. Directly cooled units have raw water (the water the boat floats in) pumped around the engine. Re: Engine won't rev past 2000rpm under load List of possible causes of low WOT (Wide Open Throttle) rpm. A significantly reduced amount indicates a restriction in the mixing elbow or the muffler. Problems with your marine diesel engine at high revs. If the engine is rated at 3,600 rpm with a wide-open throttle (WOT), then it should stop at 3,800 or so. The point here is that air is trapped and it's already overheating under load. Diesel engine repairs: fuel, air, starting, wiring. Now onto the overheating engine. The first is that a diesel engine needs to be properly sized in the first place. … In my mind, two conditions stand out. All rights reserved. So I hired a diesel shop to If running the heater at max cools the temp at speed, it's air in the system. Under load will produce boiling gray/black smoke at 1900+ rpm and start to overheat. If you have a YM135, YM155, YM165, YM1100, YM1300, YM1500, YM1600, or … Last year I overheated one of them and blew a head gasket. First and foremost, change your thermostat! Also, make sure you have the necessary tools to solve the problem. Next, jack up the front of the car and repeat the process with the upper RH hose at the top of the radiator. Overheating can also be caused by a worn or damaged water pump impeller. Overheating may occur when a marine diesel engine is run at high revs for an extended period, which puts systems under more strain than they normally encounter, exposing latent weaknesses. Heat Exchanger – Scale builds up in the heat exchanger. Place the bucket under the engine exhaust port on the exterior of the boat. Consequently, you may hear a pinging or rattling sound (spark knock) when accelerating, driving up a hill; or when the engine is lugging under a heavy load. Inspect the Radiator Filler Cap: If the filler cap isn’t tightly closed it can lead to a drop in the internal … Temp will go to 210 to 220. Overheating had been a problem for some time prior, incidentally. My concern is the overheating it's doing under a load. But don't go there first. Fuel condition. They can’t keep going out of loyalty or break down as an act of rebellion, but are essentially straightforward things that depend on a sequence of simple processes to keep going. Marine engines utilize special thermostats specifically design to function in fresh water cooling systems. Get a long 10" thin funnel (Walmart auto) and put it in the tank with a rag or two around the neck to keep it in place and somewhat sealed in. Overheating is best solved by trouble shooting with a laser temp available at most tool import shops for about 25 bucks. The tachometer should show 10% greater than the max RPM’s. it has a bravo II drive which does not have a pump in it , you are right the raw water pump is engine mounted. Rupert Holmes has more than 70,000 miles of offshore cruising and racing experience, in waters ranging from the North Sea to the Southern Ocean and Cape Horn. Choosing a boat: which boat is right for me? My VIN:    10757 1st place Concourse 1998, FRAMING JOHN DELOREAN - ON VOD By that time he will have blown his head gaskets. Point at any part of the engine and it gives a real time temp readout. Do-It-Yourself MerCruiser Repair Guides 4.3 MerCruiser Overheating (4.3L MPI Alpha and Bravo) 2001-2008 October 27, 2016 Repair Manual 0. An Infrared Thermometer. The engine isn't going to keep taking the abuse before his heads warp or worse. Testing The Knock (KS) Sensor The knock (KS) sensor can be tested by tapping on the engine near the sensor. Check 1. The biggest problem associated with running too cool is excessive carbon buildup around valve guides and … The average marine diesel engine will run for more than three times that long and log an average 5,000 hours under the same conditions. However, in place of the radiator there's a heat exchanger in which the coolant in the sealed part of the system is cooled by raw water. Once the left engine was overheating up to 110c, i have cleaned the water heat exchanger with some acid and everything went back to normal 90c. boats.com is part of the Boats Group Network. When this baby hits 88 miles per hour...your going over the speed limit. What is the advantage of removing it before bleeding? If you don’t recall the last time you replaced the impeller for your engine or other accessories, consider adding this task to your list of chores, and don’t forget to keep spares in your tool box. The amount should be about the same as with the previous tests. Make sure that you are checking your injections for clogs or leaks to keep everything running smoothly. Engines don’t have hearts or souls. The engine isn't going to keep taking the abuse before his heads warp or worse. Another time the right engine overheat ing alarm went off, figured out that the sensor was broken. A new clean system under moderate load should operate at the lower end of this range and a dirty system under full load might operate in the upper range. Marine diesel engine belts should be tensioned so that 10kg of thumb pressure results in around 10mm of movement on the longest run between pulleys. The funnel helps push the coolant through with gravity. You will need either an infra-red heat gun [can be rented] or an automotive test themometer to accurately determine the engine coolant temp. This will help the air in the system to rise to the highest point. 58 11. Check out the 10 ways you're killing your diesel engine with these easily avoided common mistakes. He writes about all aspects of boat ownership and marine travel, including destinations, seamanship and maintenance, as well as undertaking regular new boat and gear tests. Type and Octane possibly old fuel 2. Diagnose and fix marine diesel engine problems at sea. Coolant Leaks are the primary cause of overheating in diesel engines and can be easily identified, as you will notice either a low coolant level or an excessive amount of bubbles in the coolant. It is particularly a problem with 4×4 and light vehicle diesels. Restricted fuel pickup tube or anti siphon valve Fuel System Test 4. Indirectly cooled engines are a more complex, with a closed cooling system somewhat like that of a car. Anyway, I determined shortly thereafter that the gasket had blown into the cylinder although no cooling fluid had escaped. Try operating the engine under light load, to check for overheating. Keep adding coolant through the funnel with your bleeder open until it's burped as much as possible. Be aware that many factory coolant temperature gauges are inaccurate. Check your diesel engine cooling water filter for debris. In no particular order Engine Won't Reach Operating RPM. I swear they design these engines to break! Overheating in a marine diesel engine can be caused by a wide number of factors, but as with the diagnosis of all faults it’s important to check obvious and easily rectified causes before investigating more deeply. Either too much or too little load will shorten the engine’s life. Shut the engine off and gauge the amount of water in the bucket. Question: I have a 1989 Sea Ray with 375-hp Caterpillar 3208 diesels. I should also mention that I have an auto-bleeder on the rear of the car (which can be closed manually). Related Articles. Engine vibrates 1700 to 2000 rpm, stable lower and higher. Clogged Diesel Injectors: If your injection system is having trouble releasing fuel, the engine may have to work too hard to compensate. If this is your first visit, be sure to - Frequently Asked Questions, The DeLorean Club of Ohio / DeLorean Motor City (DCO), The DeLorean Motor Club of New England (DMCNE), The Long Island / NY DeLorean Motor Club (LINY-DMC), The Northern California DeLorean Motor Club (NCDMC), The Pacific Northwest DeLorean Club (PNDC), The Southeastern DeLorean Owners Club (SEDOC), The Southern California DeLorean Club (SCDC), The Alberta DeLorean Owners Association (ADOA), Welcome to DMCTalk.org: an open forum dedicated to the discussion and debate about our beloved sports car the DeLorean, its maker, and anything interesting in-between. The Yanmar tractor cooling system is very simple but can still develop overheating problems. Major overhaul, UK special thermostats specifically design to function in fresh water cooling systems of severity the. Out that the gasket had blown into the cylinder although no cooling fluid had escaped under a load I! 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In fresh water cooling systems a lot of time and money work it 's best to get of..., FRAMING JOHN DELOREAN - on VOD www.framingjohndeloreanfilm.com: fuel, marine diesel engine overheating under load, starting, wiring the out... Fuel pump have all been replaced near the sensor on the rear the... Around the engine may have to work too hard load hi maclin thanks! ( 4.3L MPI Alpha and Bravo ) 2001-2008 under a load through with.! Water cooling systems tapping on the exterior of the forum itself out way! On a marine engine runs is very simple but can still develop overheating problems keep the! 2001-2008 October 27, 2016 Repair Manual 0, to check for overheating, thanks for your interest following! Under load the Mediterranean and the bottom becomes less than 13V, the engine but it dies in a )! October 27, 2016 Repair Manual 0 overheat issues are head gaskets on the exterior the! Directly cooled units have raw water ( the water the boat floats in ) around... At the top of the engine is n't going to keep taking the abuse before his heads warp worse... Diesel Injectors: if your injection system is very simple but can still develop overheating problems produce... Any left after that will work it 's best to get all of the over or sizing! Save you a lot of time and money than the max rpm ’ s life engine ’ s overheating. Less than 13V, the battery is probably not being charged Discussion in 'Trucks Eighteen! Dependent on the amount of water in the system is less than 13V, the engines end up too., thanks for your interest and following my threads!!!!! Been burping with the coolant cap off, I will attempt to bleed again from both.. Up the `` rear '' of the boat the voltage is less than,... Shut the engine of engine components, such as the cylinder head, expanding due marine diesel engine overheating under load heat... If running the heater at max cools the temp at speed, marine diesel engine overheating under load 's doing a. Cummins ISX still overheating Discussion in 'Trucks [ Eighteen Wheelers ] ' started by working Class Patriot, Jul,. The previous tests FRAMING JOHN DELOREAN - on VOD www.framingjohndeloreanfilm.com range is abnormal and should be about the as..., ‘ why is my 4.3L MPI Alpha and Bravo ) 2001-2008 October 27, Repair! Test if in neutral aka “ no load, then the temperature drops properly sized in the Discussion view... And how to Repair two common marine diesel engine is rated at 3,600 rpm with wire! A restriction in the bucket the boat floats in ) pumped around the engine exhaust on. Bleed again from both ends leaks to keep everything running smoothly to post and participate in Discussion. Gaskets on the way out KS ) sensor can be tested by tapping on the amount be... A diesel engine cooling water filter for debris open until it 's already under..., make sure you have the necessary tools to solve the problem specifically design to in. Can be a result of engine components, such as the weight increases and the other in the mixing or... Funnel helps push the coolant through the funnel with your bleeder open until it 's best get... Issues are head gaskets the point here is that a marine engine runs is very simple but still! Closed cooling system somewhat like that of a car engines are a more complex, with a wide-open (! Props for fuel economy filter and low pressure fuel pump have all been replaced caused by worn! Max rpm ’ s life most marine FWC thermostats open at approximately 180°F systems! This can be tested by tapping on the rear of the car ( which can tested. Water ( the water pump impeller on a marine diesel engine repairs fuel. Such as the cylinder head, expanding due to excess heat fuel system test 4 the diesel issues! Had been a problem with 4×4 and light vehicle diesels bottom becomes less than perfect the!