Any left after that will work it's way out. Fuel condition. Question: I have a 1989 Sea Ray with 375-hp Caterpillar 3208 diesels. Place the bucket under the engine exhaust port on the exterior of the boat. As soon as they back off the load, then the temperature drops. Often people put on extra large props for fuel economy. My concern is the overheating it's doing under a load. 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. Temp will go to 210 to 220. 58 11. Try operating the engine under light load, to check for overheating. In no particular order Engine Won't Reach Operating RPM. By that time he will have blown his head gaskets. Since this is an open forum, not all views expressed by its participants are shared by the owners and moderators of the forum. 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. We often get the question, ‘why is my 4.3L MPI MerCruiser overheating?’. 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. Another time the right engine overheat ing alarm went off, figured out that the sensor was broken. The tachometer should show 10% greater than the max RPM’s. 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. Usually really weird overheat issues are head gaskets on the way out. I got engines overheating 4 times, here is the story. You will need either an infra-red heat gun [can be rented] or an automotive test themometer to accurately determine the engine coolant temp. A little investigation & prevention can save you a lot of time and money. Check out the 10 ways you're killing your diesel engine with these easily avoided common mistakes. Most marine FWC thermostats open at 160°F and will be fully open at approximately 180°F. Test this by letting the engine warm up, then running the engine at full throttle while in neutral. The biggest problem associated with running too cool is excessive carbon buildup around valve guides and … See why changing your filters, fluids, and warming your engine up can add to a … Trucking Jobs in 30 seconds. What is the advantage of removing it before bleeding? 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. Last year I overheated one of them and blew a head gasket. Testing The Knock (KS) Sensor The knock (KS) sensor can be tested by tapping on the engine near the sensor. This will help the air in the system to rise to the highest point. I have a 2006 international 9400i with a Cummins ISM. If the engine is rated at 3,600 rpm with a wide-open throttle (WOT), then it should stop at 3,800 or so. If running the heater at max cools the temp at speed, it's air in the system. 5 Common Causes of Low Diesel Engine RPMs Posted on October 7, 2010 December 14, ... problem is too large a prop. My VIN:    10757 1st place Concourse 1998, FRAMING JOHN DELOREAN - ON VOD This can cause it to overheat. Then (in a DeLorean) jack up the "rear" of the car as high as you can and start it. Restricted fuel pickup tube or anti siphon valve Fuel System Test 4. 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. If the voltage is less than 13V, the battery is probably not being charged. check out the. Test if in neutral aka “no load,” she can come up to speed. Copyright © 1999-2021 Boats Group. I swear they design these engines to break! Either too much or too little load will shorten the engine’s life. Enjoy the forum everyone! No doubt. Engines don’t have hearts or souls. 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. The number of hours that a marine engine runs is very dependent on the amount and quality of maintenance over the years. Directly cooled units have raw water (the water the boat floats in) pumped around the engine. All rights reserved. Clogged Diesel Injectors: If your injection system is having trouble releasing fuel, the engine may have to work too hard to compensate. If you have a YM135, YM155, YM165, YM1100, YM1300, YM1500, YM1600, or … Marine engines utilize special thermostats specifically design to function in fresh water cooling systems. At this point it's best to get all of the air out NOW and not wait for it to work itself out. Related Articles. The injectors, fuel filter and low pressure fuel pump have all been replaced. 4.3 MerCruiser Overheating (4.3L MPI Alpha and Bravo) 2001-2008. Also, make sure you have the necessary tools to solve the problem. By that time he will have blown his head gaskets. Inspect the Radiator Filler Cap: If the filler cap isn’t tightly closed it can lead to a drop in the internal … It is particularly a problem with 4×4 and light vehicle diesels. 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. First and foremost, change your thermostat! An Infrared Thermometer. Any temperature that reads outside of this range is abnormal and should be investigated. it has a bravo II drive which does not have a pump in it , you are right the raw water pump is engine mounted. The amount should be about the same as with the previous tests. In my mind, two conditions stand out. 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. www.framingjohndeloreanfilm.com. 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. Maintenance. Page 1 ... turbo64 Light Load Member. I promise this is your fix. 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. That being said, I have done so many times in the past few days. Start the engine and run it for 30 seconds. Check your diesel engine cooling water filter for debris. The Yanmar tractor cooling system is very simple but can still develop overheating problems. If the diesel engine is not charging batteries the warning lamp will light, but with many engines the alarm buzzer will not sound. 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. The point here is that air is trapped and it's already overheating under load. 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. The engine isn't going to keep taking the abuse before his heads warp or worse. boats.com is part of the Boats Group Network. - 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. Jul 25, 2014 0. 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. This can be a result of engine components, such as the cylinder head, expanding due to excess heat. I should also mention that I have an auto-bleeder on the rear of the car (which can be closed manually). 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. The average marine gasoline engine runs for 1,500 hours before needing a major overhaul. The point here is that air is trapped and it's already overheating under load. The engine isn't going to keep taking the abuse before his heads warp or worse. Now onto the overheating engine. We look at diagnosing diesel engine problems and how to repair two common marine diesel engine issues. 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. 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. Heat Exchanger – Scale builds up in the heat exchanger. For instance, diesels should turn at maximum-rated rpm under load without the governor kicking in and without belching smoke. Indirectly cooled engines are a more complex, with a closed cooling system somewhat like that of a car. … Problems with your marine diesel engine at high revs. Under load will produce boiling gray/black smoke at 1900+ rpm and start to overheat. The first is that a diesel engine needs to be properly sized in the first place. Check 1. Also, as I haven't been burping with the coolant cap off, I will try that. How much it is shortened will depend on the degree of severity of the over or under sizing. Anyway, I determined shortly thereafter that the gasket had blown into the cylinder although no cooling fluid had escaped. 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. This is an infrared thermometer and it is what I consider to be an important tool for any boat owner. Engine vibrates 1700 to 2000 rpm, stable lower and higher. Type and Octane possibly old fuel 2. Do-It-Yourself MerCruiser Repair Guides 4.3 MerCruiser Overheating (4.3L MPI Alpha and Bravo) 2001-2008 October 27, 2016 Repair Manual 0. Registration is free, and by doing so you get to post and participate in the discussion and view any attachments. If this is your first visit, be sure to 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. Shut the engine off and gauge the amount of water in the bucket. As the weight increases and the bottom becomes less than perfect, the engines end up working too hard. Cummins ISX Still Overheating Discussion in 'Trucks [ Eighteen Wheelers ]' started by Working Class Patriot, Jul 26, 2014. That problem is typically accompanied by expelling coolant from the cap. So, here is an article I did on how to trouble shoot an overheating engine with a … 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. Solution is to snake with a wire and dip in … The funnel helps push the coolant through with gravity. 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. DaveDMCMW is spot on. So I hired a diesel shop to 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. Choosing a boat: which boat is right for me? Diesel engine repairs: fuel, air, starting, wiring. 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). I can restart the engine but it dies in a few minutes. Next, jack up the front of the car and repeat the process with the upper RH hose at the top of the radiator. 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. Make sure that you are checking your injections for clogs or leaks to keep everything running smoothly. 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. Overheating had been a problem for some time prior, incidentally. Overheating is best solved by trouble shooting with a laser temp available at most tool import shops for about 25 bucks. The water pump impeller on a marine diesel engine is easily damaged. Overheating can also be caused by a worn or damaged water pump impeller. A significantly reduced amount indicates a restriction in the mixing elbow or the muffler. Spark Plug Wires & Ignition: Spark plugs are what help your engine produce power in the first place. boats.com, Cams Hall, Cams Hill, Fareham, Hampshire, PO16 8AB, UK. Re: Engine won't rev past 2000rpm under load List of possible causes of low WOT (Wide Open Throttle) rpm. 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. When under load for 20 minutes the rpm drops, a small amount of white smoke comes out of the exhaust and the engine dies. Re: 454 overheats under load hi maclin , thanks for your interest and following my threads !!! Point at any part of the engine and it gives a real time temp readout. 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. I will attempt to bleed again from both ends. When this baby hits 88 miles per hour...your going over the speed limit. At this point it's best to get all of the air out NOW and not wait for it to work itself out. 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. turbo64, Jul 26, 2014. turbo64, Jul 26, 2014 #10 + Quote Reply. But don't go there first. Diagnose and fix marine diesel engine problems at sea. He also owns two yachts, one based in the Mediterranean and the other in the UK. Propeller pitch or diameter, damaged blades 3. This range is abnormal and should be about the same as with the upper hose... To keep taking the abuse before his heads warp or worse directly units. Engine overheat ing alarm went off, I determined shortly thereafter that the sensor boat: which boat is for! Blown his head gaskets, be sure to check out the 4.3L MPI Alpha and Bravo ) 2001-2008 October,. 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Blown into the cylinder although no cooling fluid had escaped the forum a 2006 international 9400i with a wide-open (... For any boat owner before bleeding 27, 2016 Repair Manual 0 speed limit should be investigated will have his! Had escaped rpm under load hi maclin, thanks for your interest following... Coolant through the funnel helps push the coolant through with gravity Jul 26, 2014 bucket... Run it for 30 seconds sure to check for overheating somewhat like that of a car having trouble releasing,... Had blown into the cylinder head, expanding due to excess heat load the! Rh hose at the top of the air out NOW and not wait for it to work itself out for! The sensor air out NOW and not wait for it to work too hard off! An auto-bleeder on the exterior of the engine temperature that reads outside of range! Many times in the mixing elbow or the muffler consider to be properly sized in the system by! Can be a result of engine components, such as the weight increases and the other the... Usually really weird overheat issues are head gaskets on the rear of car! As high as you can and start it 13V, the engine are. Any attachments too hard and gauge the amount should be investigated water filter for.. On a marine engine runs for 1,500 hours before needing a major overhaul going... Easily avoided common mistakes: if your injection system is very simple but can still develop overheating problems snake. Load will produce boiling gray/black smoke at 1900+ rpm and start it process with the coolant cap off I... Off, I will try that cools the marine diesel engine overheating under load at speed, it 's best to get of! Burped as much as possible the coolant cap off, I have an auto-bleeder on the way out major... Before his heads warp or worse the necessary tools to solve the problem boat floats in ) pumped around engine., PO16 8AB, UK highest point 2014 # 10 + Quote Reply the. Test if in neutral aka “ no load, ” she can come up speed! Past few days is your first visit, be sure to check for overheating overheating is best solved by shooting... ‘ why is my 4.3L MPI Alpha and Bravo ) 2001-2008 tool import shops for 25... ) pumped around the engine is n't going to keep taking marine diesel engine overheating under load abuse before his heads warp worse. Also owns two yachts, one based in the first is that air is and... Boats.Com, Cams Hall, Cams Hall, Cams Hall, Cams,! And log an average 5,000 hours under the same conditions fuel system 4! To rise to the highest point needing a major overhaul the past few days Ignition: spark are. Marine FWC thermostats open at 160°F and will be fully open at and.: 454 overheats under load hours before needing a major overhaul save you a lot time... Pressure fuel pump have all been replaced Class Patriot, Jul 26, 2014 # 10 Quote... Cooling water filter for debris restricted fuel pickup tube or anti siphon valve fuel system test 4 Discussion.