In future : Turn off the petrol before stopping the engine, keep it running until it either starts to 'race' or starts to 'hunt', then turn off the ignition and the carb will be dry and won't get gummed up. Forums So stupid to make assumptions like that. And clean and adjust the carbs as mentioned already.As the engine is old these things may have not been done for a long time, or ever done. Boat, Boat Buyers How does it act at idle Does it stumble when to push the throttle? Viewing 11 posts - 1 through 11 (of 11 total), trim.20FEEC57-AFBE-4047-A68E-C8A96CE83816.mov, For Sale: Left Handed Rifle Remington 700. Ran awesome for a couple months then developed a similar problem to yours. This engine have single carb? Everything was smooth as butter and then it would come very close to stalling out before saving itself and coming back to a normal idle. It seals just fine. Covers, Boat Cover Adjust it with a spark plug gap tool if necessary. Hitches, & and thanks cereal tiller, I will have a look at how to drain the carburetor. Rafts, Paddle Smoke Forums, Find If youre not sure where to begin, then youve come to the right place. Typically outboards have a mechanical link that advances the ignition as you open the throttle. Telescopes, Covers and 
Another common issue that you may need to troubleshoot is vibration. Trolling Motors, Shop outboard stroke cdi freshwater mn hp unit engine ecu ignition yamaha 2002 A forum community dedicated to Small Skiff owners and enthusiasts. Now, Shop yamaha hp outboard 2stroke line When the engine is cold, I usually have to keep revving (and sometimes rapidly pulling out the choke and pushing it back in) to keep it running. Detectors, Binoculars & I did manage to foul a plug on mine from idling a bunch and it caused the motor to act up. Systems, Marine Plumbing This helps enormously when you come to put it back together and you can't quite remember where that little spring came from and where it should go back! It has just snapped in two so mystery solved. I have a 1997 Yamaha 25 HP (MSHV) outboard. Ha ha. & Dollies, SportsStuff Great Big Trailer Winches, Shop Once you have seen it done its quite a simple operation and well within normal 'DIY' skill requirements. Yes it is a snapped throttle cable!!! PFDs, Roof Racks, Carriers, lucyboatgirl, Someone just said to me that it was probably a fuel issue and I totally believed it without investigating myself! First, check the fuel system to ensure there is enough fuel in the tank. No matter what model you have, there will eventually come a time when you may need to troubleshoot some common issues. Deals, Electronics 
TheFamousGrouse wrote:
Software, Digital Even when I gunned the throttle it still just stayed in low revs. It's a part of the carb float bowl. powerhead remanufactured Shop Bilge Pumps, Shop I suppose you have unscrewed the air vent screw that is normally in the tank filler cap! But I will be spending a lot of today watching youtube videos to try to learn about this stuff. Start by unscrewing and removing the electrical cover. Tackle Boxes, Fishing Bait & Boat Repair, Boat Paint & Fuel issue? Nonetheless, this is the kind of help I need! Deals, Pumps & Plumbing Next, check the fuel lines that connect the Yamaha outboard motor to the fuel tank. How do you take it off? I didnt actually know this was a thing. 
yes compression make a big difference in how well a motor runs, so you can get a loaner tool at most auto part stores and pull all plugs to test all cylinders. If the level is below the L mark, you should refill the tank. 
Remember to connect the positive first and the negative second. installed a new gasket. I used grease on the thermostat housing gasket to prevent it from sticking so that I can re use it. Switches, Shore Power & AC yamaha outboard hp stroke manual f25 If you cannot keep it running long enough to make an adjustment then open it one quarter turn and see if that improves things. Boarding, Paddles & Maintenance, Pumps and stroke freshwater ecu outboard cdi ignition mn yamaha hp unit engine Ski, Wakeboard Blocks, Marine Parts, Boat Tubing & Covers, Boat Seat Maybe not your same problem but would not hurt to look. & Dock, Anchor Chains & Alan de enfield thanks so much for taking the time to write that for that really careful and detailed guide. TIP: when you replace the cable, do NOT try and force the stick into reverse (to test things) when the engine is off. My little 2hp 4 stroke had a blocked jet one year when i forgot to drain the fuel over winter, fairly easily cured if you can find instructions. If it will still not clear, go back outside, (off the boat) pour some petrol into a tub and put the jet in to soak for an hour or so, dry off and try blowing thru it again. I moored up and had a look at the prop and pulled some weeds out but nothing serious and then tried her again. Either find a way to submerge the lower unit in a trash can, barrel, etc or do this at a quiet public access with the boat in the water. Kits, Boat Trailer I went through the fuel pump again and found a small hole in diaphragm. All content remains the copyright of its respective owner. I took a video of the issue but its too big to attach here. 
Wipe the dipstick off with a clean cloth, reinsert it, then remove it and check the oil mark. ^^^^ Dirty jet or bad fuel pump (some motors have just one fuel pump, others have two). 
Rollers, Boat Trailer Yes, but I would not bother for an overnight shut-down or for a day or two. yamaha hp stroke 25hp Next time it gasps, pump the primer bulb. Make sure the motor is upright and level before removing the oil filler cap and dipstick from the oil tank. Note the original position of the screw before you start making adjustments. Carefully record every adjustment you make. Tops, Other Unfortunately neither the adjustment to the fuel/air mix or pumping the bulb made a difference. Did some fishing on the trolling motor (just one pike) and then ran around at full throttle for a while and brought it back to the dock to tinker. Fishing Forums Plumbing, Anchor Erics Outboard Marine has created this guide with some tips for troubleshooting your Yamaha 4-stroke motor. Could also be a fuel line problem. Use the hairbrush bristle again. Remove the Spark Plug(s) and compare, are they grey or black and are they both the same colour? I have taken it out twice since then and the motor runs good so far thanks again. Copyright 2019 IBOATS. Varnish, Marine Adhesives, Parts, Wash Down 
outboard Remove float (watch for fuel shut off pin falling out and getting lost), You will find the main jet 'inside' the top of the 'bowl' screwed into the body of the carb. Holders, Cabin Accessories & Biminis, Paint and Does it continue to run after the problem shows up? No, I haven't checked compression - not exactly sure how to do that (buy a gauge and test it in the spark plug holes?). Don't discount a dirty/ clogged fuel pick in the tank itself. Looked motor over real good and found loose bolt. Guide, Boat Once again, if you find damage, youll need to take it in for repairs. Seats, Offshore Boat You are using an out of date browser. Combos, Fishing Tools & Does it just quit if you idle too low? If youre the proud owner of one of these engines, you know how powerful and reliable they can be. Systems, Lowrance Hook2-4 GPS All connectors are clean. Adjust from there. water under the bridge. Thanks for all or any help you can offer. 
Maybe it's going into limp mode? 09 25 ESH similar problem. All content remains the copyright of its respective owner. Good advice though. Dock, Cabin and Holder, Anchor & Dock Storage ha ha! Furniture, Boat Seat Pedestals & Cleaned and reinstalled with Blue loctitie. I thought the carbs were dirty for sure so I rebuilt them and all three looked perfect. They all seemed pleased that I wanted to learn and were happy to teach me. x, You need to be a member in order to leave a comment. For a better experience, please enable JavaScript in your browser before proceeding. Grills, Boat Drink Meters, Marine Electrical Panels yamaha hp outboard 1994 lower stroke unit cyl freshwater mn motor Accessories, Boat Blow down the holes and try and clear them, if you cannot, then try a single bristle from a hairbrush or toothbrush and gently poke it thru. Sorry to have bothered you all with this mystery problem when a simple look around my engine would have totally confirmed what it was. Remove them with a spark plug wrench so you can inspect them. ha ha! Hardware, Boat Cabin Deals, Electrical 
Communication, Auto Pilot Parts, Sacrificial Anodes & For a better experience, please enable JavaScript in your browser before proceeding. Have you tried adjusting the carb to richen the mixture a little? Platforms, Slide yamaha 90 outboard stroke hp manual 90hp service repair 2006 1996 engine manuals ec21 Motors, Fishing Downriggers & But I don't understand how you would 'turn off the petrol' before the engine? Deals, Dealer There are a few steps you can take to troubleshoot starter issues. Kits, Seadog Stainless Steel Cup Ideally remove the carburettor (normally just 2 bolts), disconnect fuel hose, disconnect throttle and choke cables and remove from the engine. Like a right numpty. All, Boat Bimini Hardware, Boat Seat Sweet! But I noticed that if I left it idling in neutral, it would seem to gasp for fuel. Alternatively, if you find the level is above the H mark, you should remove excess oil with a syringe.Your last step involves the spark plugs. still blocked ? Acessories, Fishing Outriggers & Shelters, Boat Restart the engine to see if the vibration has stopped. Lighting, Marine Teak Any suggestions where to start? If youre experiencing issues with the engine starting or running, there are some troubleshooting steps you can try.
