Boat Low Rpm At Wot







I have a 1984 champion Bass Boat 20 foot fish and ski With a 2. 4 I/O New Topic On my last boat I would get slower and slower through out the season at the end of the season I would empty the boat to. Eastern18 low rpm at WOT. How do I test coil? F series (07- ) This is a brand-specific forum. Sam Holmes. Octane of fuel 9. You are now down to a WOT RPM of 3400 on one engine and 3350 on the other, & WOT speed is only 23-24 K’s. The highest load for a boat is at pre-planing speed and {wot (planing hull or not)}. So I am thinking that my motor is too low. The boat is a 2007 Maxum and only had 26 hours when I bought it so it has been sitting around quite a bit the past few years. If RPM's are at the upper end of the range with a 3 blade prop, use a Revolution 4 of the same pitch. At WOT the rpms will typically peak out at 5650 (sometimes the high 5500's to very low 5700's) with a top speed of about 38 mph via gps and spinning a Yamaha Saltwater Series II 15. Could someone please tell me what RPM range I should be in @WOT? The >boat is currently turning only 4500 with a 19 pitch aluminum prop. The boat is trailered, but upon inspecting the hull before we put it in the water, I didn't see anything that would be stuck on the bottom creating drag. Tachs have been verified with a phototach at low rpm but not high yet and belts seem tight on both engines. This helped somewhat but I'm still reaching 5000 at WOT / 43. keep going as long as the boat keeps picking up a little speed. Sunseeker Predator 57 boot te koop, Motorjacht, Overig, € 1. The unplugged wire obviously might explain why I went from 3400 to 4000 rpm with new fuel cooler and injectors, but still was missing the last 600-700 rpm. Transmission gear ratio 7. Discussion in '"Pocket" Downeast Boats (14-24ft)' started by Crawdad20, Sorry if I am mistaken but didn't you add the keel to your boat. Electrical System. I tried several props and now I am pulling 5,600 RPM at WOT and 18 mph on the speedometer and 15-16 on the GPS with three people on-board. 350 Mag MPI Mercruiser only doing 4000 RPM which theoretically increases wot rpm. Boat makes about 20. 3 On average accel I get upto 2-4PSI and at WOT under dp-tuner econo80 I get about 10 PSI. Type and Octane possibly old fuel 2. Obviously the best GPH any boat will ever get is either sitting at the marina, or at idle, that's not what I'm talking about. I couldn't find anything in the owner's manual to say what RPM I should ideally have for a given speed. There no difference in rpm or boat speed at 3/4 or wot but at wot the motor has more of a growl rather than a high pitched 2 stroke whine at 3/4. We normally cruise at less than 1,500 rpm to conserve fuel and relax, but I have no worries running at 3,000-3,200 rpm for extended times (other than my wife's comments at the fuel dock). In the past this boat ran just shy of 75mph GPS @ about 5800 rpms with the same prop etc. RPM at WOT too low? (Mercruiser 3,0 TKS) Was quite surprised with the results, however started to select a replacing prop until one experienced Mercruiser local dealer calculated with Mercruiser software and told me that actually boat should reach specification WOT of 4400-4800 rpm with 21 pitch prop and 400 kg load, speed should be approx. An engine is designed to run at wide-open-throttle (WOT), within certain rpm limits. Checked the cable connection at the carb and realized it wasn't opening up all the way. How bad is low rpm 5th gear pull? After about 3 weeks of having my new OBP '12 WRX hatch (and with a lot of patience) I finally passed the 1k mile break in period after work yesterday and wanted to get a good feeling for how the car accelerates. Operating Amps. You can use a lower pitch propeller for better take off, just do not go over your recommended wide open throttle RPM range at full speed. if you park it after waiting awhile it would be back to normal, about a month later it was then having a no fuel pump prime situation where it. If the RPM is higher, switch to a propeller with higher pitched blades. Engine RPM Chart for Proper Boat Propeller Sizing. Thoughts? Anyone know if this can be done while the boat is in the water. Consider that if one were designing the drive train for a boat, there are options on the final drive ratio. 3 engines, WOT is 4000 @ 58 kmph. 110V 12W 10 RPM Light Mover Motor for Indoor Reflector Hood Rail Grow Hanger. Too much prop pitch puts extra. A 13x13 prop was quite common for non powerslot transmission boats for many, many years and WOT for the direct drive Mastercrafts has almost always been between 4400-4800 rpms. If the actual WOT RPM's are above the recommended RPM range, install the next larger pitch option to decrease your WOT RPM. 0not long ago i gave my engine a tune up and took it out for a test runthe water was calm with just a slight breezethe bimini top and flag were down and i was by myselfi had about a 3/4 tank of gas and around 6 gallons of fresh watertrim tabs were raised all the wayi probably had another 100 lbs in misc gear on boardi was able to hit around 4,500 - 4,600 rpm's at WOT according to my. Only pulled 105 speedo @ 7900-8000 on a corrected tach. I broght it to a merc dealer and they changed the fuel line and fuel filter and primer ball. 28-29 psi at wot drinking gas 200 rpm loss 250 pro xs low slung cruiser. Welcome to the Internet's premier site for boat motors! This site is part of iboats. At the landing, for the second hour, I change props to 13 5/8 X 15 pitch. Re: Yamaha 9. You really cant tell what any prop will do until you take it for sea trials. Normal operating Elevation 10. Evinrude E-TEC G2 150 HP Outboard, Control System 2016 The Evinrude E-TEC G2 150 HP delivers impressive fuel-efficiency plus high torque in the low- and mid-range rpm bands, which owners of bass boats and watersports enthusiasts will appreciate. It does run a bit better in the cooler times of year, but nothing significant and no difference in RPM's that I've noticed. it only happens when im low rpms and go WOT ive read on here that once you put a after market WGA that you learn to drive diff?. On the other hand, spark knock is primarily an audio thing- you hear it but do not feel it. A month ago I took my boat out on a 300NM journey and only got 1. When the engine RMPs approach 1700 and the power is still consistent, but the engine starts to vibrate and has a rough run from 1700 RPMs to 2700 The miss firing has been constant since the 1st hour (585) that I used the boat to current hour (685). Eastern18 low rpm at WOT. Speed at WOT was 45. I know the cam is large and the main reason for this problem. Anyway, my RPM was reading 5000 @ 53 mph. 0L EFI 240 All 4400-4800 1. #1 PERIOD is WOT (engine RPM at wide open throttle) most engines have a 400 to 500RPM window at maximum RPM. Fen Delfin is a great & original example of the popular Freeman 26 river cruiser. If the prop is too large, the engine will be stuck below the minimum WOT rpm. When you combine all these factors, you have the information you need to select the correct propeller for maximum performance, safety, and fuel efficiency. i currently running a 23p mirage factory prop but also have a 21p mirage i havent tried yet. Firing Order. Re: Low rpm problem at wot Bullet At Pioneer Marine in Tampa (now defunct), somewhere in the 1980's, a brand new 70hp or 75hp (I forget which), straight out of the box, just installed by the riggers they couldn't get it running properly worth a damn and called me to check it out. I don't know what kind of propeller is on the boat, but I can't imagine that alone would be limiting it to such a low speed and RPM. Transmission gear ratio 7. 7L 300hp motor in a 20 foot boat. Current Great Ouse river safety license. You're losing tranny oil so it's leaking somewhere. 61 volts and the idle may vary from motor to motor. Although I'll be new to cruising, every boat I've ever owned had that certain speed/RPM where the ride was comfortable and the GPH was about the best it was going to get, for that speed. The impeller would have dictated his wide open throttle,a smaller impeller would let him go a little higher, but a hamilton and a at312 are designed for different things, the 312 is a pressure pump which revs a lot higher to move the same amount of water. Thoughts? Anyone know if this can be done while the boat is in the water. The other reason, is that the 454 makes gobs of torque at a low rpm. You want your RPM's to be within the proper range while at wide open throttle (WOT). - set fuel in the low to mid rpm/any kPa to the desired lambda - predict fuel in unvisited cells - set timing to MBT in the above cells - predict timing in unvisited cells - sweep tests at the lowest boost to get correct timing at WOT - increase boost and new sweep tests till a limit is reached. The advice of those guys appears to be prop the boat to achieve 50-100rpm over the rated WOT rpm in order to maximize engine life. I tried several props and now I am pulling 5,600 RPM at WOT and 18 mph on the speedometer and 15-16 on the GPS with three people on-board. the 15X15 with an aggressive cup gives me the best performance on the water. As I slowed down the rpm a. The motor is mounted on a 15 foot centre console so should be seeing figures of around 33/34 knots. Someone suggested that the High RPM's may be a sign of a low compression issue, possibly caused by worn valve seats. sounds like you have a carb model. In no particular order Engine Won't Reach Operating RPM. Your WOT should be 4500+. Could it be a fuel issue not delivering enough fuel at high consumption? Otherwise, do these boats ever need the throttle cable adjusted to correlate the WOT to full power on the engine?. I am pretty sure when I have 4-5 persons in the boat I still get around 6K RPM WOT, but the speed drops to around 37-38 MPH. As the rpms increase to 3000 and above the starboard engine lags behind and won't make 4000 rpm even at wot. This 2001, 40 hp Yamaha is made for saltwater. The engine will run a bit loud when not running at lower rpm, then all of a sudden it will run perfect until the next time I turn it back on. My brief experiments have determined a max observed rpm of 5300 while speedometer showed around 51-52 mph. My question is how much does the CPP help low rpm operation?. I ran the boat for the first time at WOT and hit 4500 rpm against a range of 4400-4800 and GPS speed of around 42 mph. However, I have FAE also, which I believe slows the thing down 3 or 4 MPH and a few hundred RPMs. At WOT trimmed up I had a steady alarm go off twice and it would go away once I pulled back. The boat has a factory aluminum 14. During the sea trial, it only made 3900 rpm WOT and the starboard engine was backfiring. With a heavy load of three anglers, tackle, ice, and 60 gallons of fuel the engine turns 5850 RPM at WOT. Our user id is: skipwhite, and our store name is whiteperformance1. 3L 190 All 4400-4800 1. If it still doesn't get to the proper WOT RPM, I would look at the fuel supply system. While the ECU certainly could be the issue I would think it would be way down the list of possibilities without further indicators, check your oil at every outing not only so that your not low on oil but that it's not overfilled (indicator of fuel being mixed in). Anything else you want to add that may make performance different. Now you set the throttle position sensor voltage to around. i have the above mentioned motor. A tachometer ("tach") measures engine rpm while the speedometer measures boat speed in mph. BENEFITS Tohatsu 4-stroke 115HP High output alternator produces 30 amps of power at 1,000 rpms and 40 amps at 2,000+ rpms Available in 20” & 25” shaft lengths In-line 4 cylinder for excellent performance and sleek design Double sealed multi-layered paint process to help protect against corrosion Ultra-low 3 star CARB emission approved 5 Year limited warranty Need a new boat?. It had good compression, new plugs, points, plugs, wiring, rebuilt carb, etc etc. I prop my pontoon to run in the top of the RPM range (11 pitch on my 55 HP 20 foot boat) so that if I load it down I don't get bogged down running WOT at under the recommended range, which is not good for old 2 strokes. 8 mph @ 5700 rpm (gps). You can find this in your operator's manual, expressed in terms of a certain horsepower at a certain r. Note: WOT (wide open throttle) measurements are made with a tuned engine, a clean boat hull, loaded with an average boat load, and the propeller clean and undamaged. I had a similar problem (low WOT RPM) with my Wonderful high tech OMC 460 King Cobra. Last time we used our boat, the engine started good and idled ok. Glad to see i am not alone. A rough guess is 200 rpm for every inch of pitch. Mercruiser 502 Mag Mpi with a WOT of only 4000 RPM? I recently installed a newly rebuilt Mercruiser 502 Mag Mpi with Lightning Headers into my Mariah Z302 and now have past the 10 hour mark of the break in procedure and really am not sure if I have an issue with the motor or do I just need to swap the Bravo Three props to a lower pitch. If the actual WOT RPM's are above the recommended RPM range, install the next larger pitch option to decrease your WOT RPM. If you don't have a tach you need to take it to a marine dealer to make sure that it is has the right prop. 16' aluminum boats are popular and a 60-hp engine will typically propel them from 25 mph to 30 mph top speed, depending on load. 6 displacement. >How could you run your boat at wot all the time because there isn't >enough lake or smooth conditions on an ocean to pull it off. If your prop is too small, the engine will over-rev. • Low fuel pressure (RFI and DI models) • Check fuel pump pressure output • Jet pump related problem • Check propulsion components. It sounded smooth but would not go above 3500. It also developed a miss from idle to around 2200 RPM. In neutral it will rev to 5500 rpm but I notice when we are going down the lake it only gets about 3300-3500 rpm. Gave it another short burst at WOT and got 3600 RPM and reached 29 MPH again. I have a '92 Mariah with a PCM 5. Is this normal?. RPM at WOT is about 4000 with 3 people and a fulltank of gas. Low prices on 3 Car, qualified orders ship free. If I back of to 3/4 it runs fine. Plus, to make matters worse, at your cruise RPM of 3200, the boat is only making 19. The valve trains are good for 5500, and the rest is fine at those low RPMs as well. By landing in the middle of the range, you've got some leeway for the rpm to drop when the load is heavier, or go up when the load is lighter. When the engine RMPs approach 1700 and the power is still consistent, but the engine starts to vibrate and has a rough run from 1700 RPMs to 2700 The miss firing has been constant since the 1st hour (585) that I used the boat to current hour (685). The boat is a 2007 Maxum and only had 26 hours when I bought it so it has been sitting around quite a bit the past few years. Currently installed 10-64's. Is this prop situation or can the spark plugs be bad? (or other suggestions?) I do not know what props I have as it is still in the water. The boat has a factory aluminum 14. Note: WOT (wide open throttle) measurements are made with a tuned engine, a clean boat hull, loaded with an average boat load, and the propeller clean and undamaged. - set fuel in the low to mid rpm/any kPa to the desired lambda - predict fuel in unvisited cells - set timing to MBT in the above cells - predict timing in unvisited cells - sweep tests at the lowest boost to get correct timing at WOT - increase boost and new sweep tests till a limit is reached. There no difference in rpm or boat speed at 3/4 or wot but at wot the motor has more of a growl rather than a high pitched 2 stroke whine at 3/4. It does run a bit better in the cooler times of year, but nothing significant and no difference in RPM's that I've noticed. If the actual WOT RPM range is below the recommended range, install the next smaller pitch propeller to increase your WOT RPM. Prop dimensions (# of blades and pitch) 8. You should rule out low gas pressure. Low fuel pressure would cause the motor to buck, rpms come in and out. sometimes a couple inches pitch change can make 1000 RPMs difference but I don’t think that’s the problem. A few years ago I was carrying out a sea trial aboard a single-screw trawler that a client was considering for purchase. Boat gets WOT, no smoke?? Can't see any problem here apart from the readings! You're getting max rpm, even if it was at lower boost (Which is unlikely) so the engine is giving you the full beans. So I am thinking that my motor is too low. the stress on a engine is exponential with RPM, so LUG away at low RPM if you want. The WOT for this engine is supposed to be 4400-4800. Motorisatie: 2 x Volvo 2 x D13. An engine is designed to run at wide-open-throttle (WOT), within certain rpm limits. Octane of fuel 9. Evinrude E-TEC G2 150 HP Outboard, Control System 2016 The Evinrude E-TEC G2 150 HP delivers impressive fuel-efficiency plus high torque in the low- and mid-range rpm bands, which owners of bass boats and watersports enthusiasts will appreciate. No engine power in a 350 mag MPI. I couldn't figure out why it wouldn't go over 4,000 because WOT should be between 4,400 - 4,800 I believe. Bow almost seem a touch low but boat does cruise very level. of fresh 87 oct. Something is dramatically wrong here! Experience tells me that tunnel boats are notoriously difficult to prop, i. Refer to JET PUMP • Exhaust system blockage • Check and repair and yes, I did read somewhere in the manual (but can't find at moment) that a low battery can / might cause low max RPMs. I'll be on VHF 27if you need me. I think the 150's is 5000 to 6000 RPM's, check your owmers manual. Pontoon Boat & Deck Boat Forum I trimmed up and down but just lost speed both directions so that was as fast as I could get it at WOT. Your engines may not have taken kindly to being over-loaded. Full Throttle at low RPM, or High RPM and low throttle so I just got in from a night of driving my mom's 1997 Subaru legacy (not outback) wagon around with the fuel needle just above empty. these are literally the most under stressed simple V8s that exist. If the RPM's are down from usual, it is almost certain to be a engine problem. If the RPM's are down from usual, it is almost certain to be a engine problem. No engine power in a 350 mag MPI. -engine makes book numbers at WOT unloaded (stabilizes around 4100. In the above scenario, a stock transmission might be used that would provide a 1. I drive a 98 vtir manual prelude. At the landing, for the second hour, I change props to 13 5/8 X 15 pitch. When the engine RMPs approach 1700 and the power is still consistent, but the engine starts to vibrate and has a rough run from 1700 RPMs to 2700 The miss firing has been constant since the 1st hour (585) that I used the boat to current hour (685). Max RPM at Wide Open Throttle 2. I have a 22SFXAPG SPS w/Yamaha 150 Reliance SDS. I noticed though, with 50 gallons of fuel, driving into the wind, with 2 people on board I am only going 30 MPH @4600 RPM. Easily find your stainless or aluminum prop with our PropFinder. Also maybe at the RPM your engine was surging as you put it was more a case of the boat plaining and then accerating without any more throttle and yes 4-Strokes with their different power curves can react differently and at the speed most people will wake board the boat is pushing water and the 4-Stroke will not have the low down torque at that. Any ideas to get the rpms up and get a few more mph out of it?. Refer to JET PUMP • Exhaust system blockage • Check and repair and yes, I did read somewhere in the manual (but can't find at moment) that a low battery can / might cause low max RPMs. Furuno model1623 radarGarmin echomap 70dv depth/gps/fish finderTrailer is in excellent condition. This >seems too low to me. It is a six-cylinder, two-stroke outboard motor with a maximum rpm of 5500 at wide open throttle, a spline count of 15 and a gear ratio of 1. My WOT RPM is topping out at 4000rpm as well. I keep an eye on the rpm and while the boat is on a semi-plane I start easing on the throttle never allowing it to go above 3800. If you have any questions, please email or call us at 425-353-0436 ***Please consult your engine manual for the manufacturer's WOT RPM's as this chart is only a rough guide. The boat has a factory aluminum 14. For what its worth my 17 foot console boat has a 60 HP 4 stroke and turns rated RPM (after a reprop) and I do about 26 to 28 MPH at WOT. 5 knots at WOT. Current issue is that the engine will not exceed 5000 rpms unless I lift it to the point where I'm blowing out the prop. Current Great Ouse river safety license. Never a problem. 4l EFI Bridgeport can anyone help me with what propeller to run on this setup. My best guess is that I'm having some cavitation while accelerating from lower speeds at full throttle where rpm's were high despite a relatively low boat speed?. They are the most common motorized method of propelling small watercraft. If the RPM is below the recommended operating range, switch to a propeller with lower pitched blades. Is this prop situation or can the spark plugs be bad? (or other suggestions?) I do not know what props I have as it is still in the water. Horsepower differences shown result from differences in test rpm, allowable test tolerances, and/or installation of special kit components. 4 hours ago · At such low altitudes there was the added danger of bird strike. I never run at WOT. that I habe owned the boat. Plus note the attainable full WOT RPM now, and next time you haul have the props scanned and pitch adjusted if needed to attain at least the middle of Crusader's recommended range for WOT RPM for those engines which was 4200-4400 rpm (as per my old Crusader 1988 all-engines owner's manual, which also specifies 89 octane gas. It does not die, just coughs and sputters until it's bumped up above 1600. The advice of those guys appears to be prop the boat to achieve 50-100rpm over the rated WOT rpm in order to maximize engine life. 4l EFI Bridgeport can anyone help me with what propeller to run on this setup. Normal maximum RPM = hull problem. My boat currently barely reaches 5000 rpms. It is fine on low rpm and only does it while up on plane. Part of the process involves running the vessel at full, or wide-open, throttle—what engine manufacturers often refer to as WOT. Ive got a mercury 60 hp outboard and usually at full throttle I would see around 5000 - 5500 rpm and a speed of 30 -35 however recently when reaching 5000 rpm the boat would do about 15I was told it was a bad hub my mechanic said they didn't have the hub in stock but could put on a brand new prop that I guess comes with a new hub?? no ideaanyways they put the new prop on and now the. Fen Delfin is a great & original example of the popular Freeman 26 river cruiser. Told me to try running at WOT for 15-20 min at the end of each trip to burn off fuel. After hooking up the wbo2 I saw it was lean when this was happening so I went into the main VE table and increased the values in the 800-2000 rpm range and 15-50 pressure by 103% and smoothed. The boat has a factory aluminum 14. Both are low on rpm at WOT and have been since I’ve owned it (9 months). If you don't match the parts well enough, cam, intake, carb it could kill the bottom end and never get on plane and just be plain turd. I've run at 6400 RPM and never got a beep, let alone a shut down. The Evinrude Intruder 150 HP is almost identical to the Intruder 175 HP except that it has a 150 horsepower engine. One time on the boat myself I saw the tach spin up to 5400 and about 27 mph but have not been able to replicate that. 0 mercruiser high rpm wide open and over heat; 350 magnum fuel cooler engine running hot at 4500 rpm; 350 magnum mercruiser overheats only at low rpms; 350 mercruiser boat overheating at high rpms; 350 mercruiser rough running at 3600 rpm; 5. Your boat tach is not accurate at that low rpm, unless it is a digital. 080" hull or even less. It is helpful to change large areas of the load maps for desired lambda to the target WOT ratio at first. Personally my boat does not really benefit from running at low rpm's. 0L 135 All 4400-4800 2 4. Hey guys my 70hp yamaha 2 stroke with 220 hours is only revving to approximately 3900/4000 rpm. Fuel consumption was around 24 GPH @ WOT. Please see questions below, any advice and answers to my questions on running the motor would be appreciated! Have no questions from 0:00 to1:35. A tachometer ("tach") measures engine rpm while the speedometer measures boat speed in mph. Even with a 10 micron fuel/water separator, some stuff gets by. Replaced fuel pump. 3600 seem low to me, you need to change your impeller or get some more go out of the engine, the later will probably be the cheaper. Make sure the cavitation plate is skimming the top of the water or slightly above when you are on plane and trimmedif your rpm's are truly that low? My new boat was rigged at the factory ( L6, 200 Pro ) and it's mounted too low. The full throttle RPM chart shows WOT RPM for: Evinrude / Johnson, OMC, Honda, Nissan / Tohatsu, Volvo, Yamaha, Suzuki, Mercury / Mariner, & Mercruiser. I boat on Bartlett Lake in AZ which is at about 1,600 ft elevation. Shop now!. Fuel consumption was around 24 GPH @ WOT. Thanks for the input guys. They have the same number of seats. It is a unit of rotational speed or the frequency of rotation around a fixed axis. Re-test the WOT RPM. Mine is an HO. If I stop the boat with engine at idle for a bit i can repeat this process. According to the tach, it will only turn 3000-3200 RPM's at WOT in gear. Wide open throttle RPM range chart for Mercury powered boats. No engine power in a 350 mag MPI. The boat is a 2007 Maxum and only had 26 hours when I bought it so it has been sitting around quite a bit the past few years. and not sitting too low on the transom. The broker had a mechanic look at the engines and he changed the sparkplugs and fuel filters as well as did a compression check which was normal. The subsequent sea trial produced 4100 rpm WOT. Boat is used for offshore fishing. The RPM's should not exceed 5500 RPM's. The reason that I ask is if tyou changed it out yourself, you probably have some pre- and post- change information that you could share that I'd love to get my grubby mitts on. 5 hours changing speeds every 5 minutes or so between 2900 and 4500 RPM, I went to WOT but only got 4800 RPM and 36. How do I test coil? F series (07- ) This is a brand-specific forum. Using your existing boat propeller or a new propeller, make test runs to determine the maximum RPM and boat speed. I don't know what kind of propeller is on the boat, but I can't imagine that alone would be limiting it to such a low speed and RPM. 200 hpdi low pressure fuel pump: 0. Plus, to make matters worse, at your cruise RPM of 3200, the boat is only making 19. It will cruise all day at 3000 rpm - about 18 mph. Test for Maximum RPM. Mercruiser Alpha One* WOT RPM Range Chart HP/Model Year Wide Open Throttle RPM Range* Gear Ratio 3. Type and Octane possibly old fuel 2. Typically, a one. Topic: RPM Increase by Raising Engine. Which tells me the decrease in RPM's at normal WOT is due to the increased drag from my hull bottom condition. WOT video of Max rpm. Operating Amps. They are the most common motorized method of propelling small watercraft. If the RPM's are down from usual, it is almost certain to be a engine problem. A tachometer ("tach") measures engine rpm while the speedometer measures boat speed in mph. 0 mercruiser high rpm wide open and over heat; 350 magnum fuel cooler engine running hot at 4500 rpm; 350 magnum mercruiser overheats only at low rpms; 350 mercruiser boat overheating at high rpms; 350 mercruiser rough running at 3600 rpm; 5. With Mercury Repower Financing, you can easily power up everything from fishing boats, to runabouts, to cruisers with flexible financing on the engine. correct me if i am wrong but if you run the engine at too low rpm's at wot , damage to the engine could occur. Seadoo Jet boat neutral low RPM rev limiter Daniel Bray. Boat is used for offshore fishing. I see all those guys trimming up with big cat tails while i cant trim past the motor beeing leveled with the boat. Twin MAN 680hp diesels. I'll be on VHF 27if you need me. 3L 190 All 4400-4800 1. The links below are wide open throttle (WOT) engine RPM range charts provided by Solas. Upon reaching the bay (and end of the 4 MPH zone) I find that maximum RPM is only about 3000 and speed about 15 mph (normal full throttle is 4500 RPM & 40 MPH). I tried the 140 tune and it jumped up to 13 PSI from a stop before I eased off with the RPM at 3k and the EGTS went to about 1000. In the above scenario, a stock transmission might be used that would provide a 1. Dealers often focus on one thing, WOT RPMs when selecting a prop. I can cruise at 3200 rpm and get 12 mph. The highest i've ever seen is 4200 with a very light load. high end HP. My girlfriend who doesn't know the first thing about the car even noticed yesterday -- "where's the pull?" she said. Is this prop situation or can the spark plugs be bad? (or other suggestions?) I do not know what props I have as it is still in the water. If I stop the boat with engine at idle for a bit i can repeat this process. The easiest tool for trying to troubleshoot a low RPM issue is a vacuum gauge, if the vacuum is high (numerically) say 8-10" hg then throttle butterfly issues is where to look. Dealers often focus on one thing, WOT RPMs when selecting a prop. However, when your low on RPM and lugging at wide open, your also lugging throughout the RPM range too. -engine makes book numbers at WOT unloaded (stabilizes around 4100. Bow almost seem a touch low but boat does cruise very level. If the prop is too large, the engine will be stuck below the minimum WOT rpm. wot just touchs 4600 43-45 mph just me and him on the boat with fishing equipment and maybe the tank half full oh 19 pitch prop. Now I am cruising at 2800 RPMs, and 14-15 mph. I'll check the carb a bit, but I think it is opening the secondaries. Go wot about a mile down the lake a slow down to scoop a loose 2x6 floating before someone hits it. It sputtered and hesitated on acceleration and dieseled when you tried to shut it off too quick. After that whenever I would change filter I would add sea foam 50/50. Re: Low RPM, time to repitch impeller? Mon Aug 03, 2009 1:14 pm I don't think you want to do the dist. You really cant tell what any prop will do until you take it for sea trials. Consult your Authorized Mercury MerCruiser. Started it up went for a ride. com) that lay this out in a logical way. It does not die, just coughs and sputters until it's bumped up above 1600. The number that you have now arrived at is the number of RPM you need to raise to maximize your boat's wide open throttle RPM range. being under or over propped) or you may simply want to gain better fuel economy. 8 X 17 prop. A typical outboard, for example, might be rated at 5,000 to 6,000 rpm and the proper propeller turns within that range at wide-open throttle (WOT). 5 MPH, WOT RPM too low [Archive] - Boat Repair Forum. Plus, to make matters worse, at your cruise RPM of 3200, the boat is only making 19. These numbers seem low with what I expected but I did have close to a full tank of gas, bottom paint and was a. Firing Order. V-King needs more RPM's. I attributed this to the altitude (4,870 ft. The bottom was just done, the props were pulled and checked on the block and are 28 x 32, which is the same as they were out of the factory. The links below are wide open throttle (WOT) engine RPM range charts provided by Solas. Wide open throttle RPM range chart for Volvo powered boats. Ethical Wildlife Boat Tours. 200 hpdi low pressure fuel pump: 0. No engine power in a 350 mag MPI.