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Random Quote: My wife told me to quit drinking, smoking and fishing, I think thats called Identity theft.
Wanted to bump this because it's important to all owners that have had fouling issues and or head issues.
As many of you know my motor has been a PITA since day 1. One of the symptoms last year beside the plug fouling was a noticeable drop in power. When I first got the motor despite people saying the 250 HPDI wasn't as powerful as other DFI motors, I was able to approach 46 mph with the right load. By year end I was stuck around 42, and this year on the first 5 hours it was a struggle to get to that same speed. On the second trip the motor detonated with the following symptoms: While throttling up to 4k rpms the motor suddenly cut back to 3k rpms with no noticeable noise, and then a few seconds later went back up to 4k rpms before cutting back to 3k rpms or thereabouts. I turned the boat around immediately and no more than a minute later I heard a horrible rattling noise which turned out to be the #2 getting fried. I had to have the throttle nearly full to make it in even though she was only turning 3k rpms.
The powerhead was replaced. It was noted by the dealer on the repair order that the motor was not steady or smooth but I got it back anyway. On the first trip out it was "okay" but still felt doggy. I think I overstated how well it was running because I was just happy to have it. The major concern I had is that it felt sluggish throttling up. I attributed this to a nearly full fuel tank and let it slide. On the next trip I almost lost teeth it was running so rough at idle and trolling, but seemed fine at higher rpms. It still seemed doggy. Now I replaced the Racor, a bulb or ten, a bunch of fuel lines, checked the pickup, replaced a battery and anything else I could get to. The boat ran better on Sunday on the way out, and most of the way in before stumbling while coming into the marina. That gets us to today.
A technician came out from a local shop that does on the road work. They came recommended to me by a few slipmates that have used them on all types of motors. At first I was a bit hesitant as the guy had some trouble getting the YDS going...and I knew they weren't a big Yamaha shop at this point as they did mostly Mercury/Verado work. Immediately it was clear to him the motor was f**** up. Luckily it was putting on quite a show of rumbling and stumbling. First up he checked fuel pressure which was fine. Like I'd done in the past he primed the bulb with the motor going to see if it made any difference, answer is no. The back cover came off and he started playing around with the injectors. Again, I knew the guy wasn't incredibly familiar with the HPDI as he figured out the #2 and #3 weren't firing and I explained that those two don't fire at idle/troll. No problem to me really because the diagnostic seemed to be progressing okay.
Next up he did the drop cylinder live test in the YDS. Bang, #1 cylinder throws a code 26. We cannot get it to repeat but you can only do it once or twice per the book. Knowing that #1 does fire all the time, we begin to put the pieces together. The main symptom has always been poor idling and plug fouling. I believe the motor will always be rougher than other motors, there is no way around it and I have to live with it or dump it. BUT, after I got it back this year with the new head, the roughness was teeth chattering. This was compounded by a feeling of slow throttle response or lack of power which I've mentioned to everyone including Yamaha directly on the phone several times. Best we can determine, the #1 injector is "dribbling" fuel at lower rpms. Once the throttle is pushed forward the pressure is enough to smooth it out before it repeats again at lower RPMS.
Here's the rub, we are fairly certain the #2 injector became the #1 injector during powerhead replacement. There is absolutely no doubt in this shops mind in seeing the photos I took that all of you here were right, the original failure was a LEAN CONDITION/LACK OF FUEL to the #2. If it were the rings as suspected the cylinder walls would have had a lot more damage, and the crown would not have melted through. Additional ring failure tends to result in rods getting tossed, which I did not have.
So, the #1 injector is scheduled to be replaced and with any luck, this injector has been the problem since day 1 to an extent. What puzzles these techs is why it wasn't replaced outright as if the plug was covered in aluminum in the roasted cylinder, the injector had to have been covered as well making it even worse. The combination of the motor sucking air from the butcher job at Hydrasport on the line and a slightly faulty injector that now flipped to totally faulty after it got shot with aluminum all fits the scenario I've been describing to a T.
Lack of power as I throttle up = injector not spraying right. Lack of top end= injector not spraying right. Burned hole in piston= fuel restriction ended up equaling bad injector. Bad idle situation after replacement= injector getting moved to another cylinder by mistake...a cylinder that fires at all speeds.
The other dead giveaway and I TOTALLY missed this and am a bit frustrated with myself. I label the plugs when I remove them just in case. The tech noticed the #1 was wet fouled when he pulled them today. All the others were fine, the #2 was a little dirty but that will happen when idling into the dock. The #2 was 100% slimed with back oil/sludge. The grounds, the center, and the porcelain were completely covered. Heck the porcelain was covered as far as you could see into the plug. When I inspected the previous set, all were fine/clean aside of #1, which again was totally wet fouled. We verified there is no water anywhere in the system.
A compression check was done on all 6 cylinders. The only good news in all of this is all measured exactly 125 psi. So, if any damage has been done it's minor and thank christ I took it easy on the motor as I knew something wasn't right.
I guess the question for Yamaha is this, why aren't you replacing or demanding that dealers replace fuel injectors after powerhead failures? Several people here, and the tech in the field today knew right away the problem was fuel being lean. Why just slap the same injectors back on the motor? This is what I don't understand.
I'll keep everyone posted, but if you do blow a powerhead, or notice continual fouling on a certain plug....GET THE INJECTOR REPLACED. In 300 hours the #1 threw a code 1 TIME. In 300 hours the only hint was 1 code 1 time, we got lucky. Everyone knew something was wrong, and it took basically a non-Yamaha tech (shop is certified) to figure it out by going back to his basic training.
I'll let everyone know how it turns out, but this profile of symptoms fits perfectly with this scenario, and fits perfectly with a normal diagnostic of such a condition. Once again THT was right.
Looks like someone has my luck. This is directly from Yamaha. " Injectors will now be replaced from each damaged cylinder with a powerhead replacement" If your tech or dealer is not doing so, demand it. I too have a lot experience in this now (4th powerhead 181 hours). #2 and #4 injectors replaced with latest powerhead, about 20 hours on it now, we'll let you know how it goes.
Good information, they wanted to replace all 6 today but Yamaha I guess would say no. They got a code on #1, and with the #2 being the one that fried they should be able to get them both done.
The #2 was apparently replaced. The current dealer still thinks they may have gotten mixed up and the bad one went back on the motor, but who knows. In any case the #1 injector was either also bad, or is the old #2.
I imagine having 2 cylinders running lean right next to each other cannot be good. I never got a look at the #1 cylinder on the blown head but I'll bet $50 it was showing some damage too.
I'm on fishinnant out of Sneads Ferry, N.C. Maybe I can stay up and running this tournament year. Went down on day 2 with a blown powerhead in Biloxi last year. ((was in 9th on day one)) That one really hurt. Hope to see you out there.
I'm on fishinnant out of Sneads Ferry, N.C. Maybe I can stay up and running this tournament year. Went down on day 2 with a blown powerhead in Biloxi last year. ((was in 9th on day one)) That one really hurt. Hope to see you out there.
I fish out of Snead's Ferry, too. Got my 250HPDI from Dale and Rick and it blew at 23 hrs......never sounded or ran right after the new power head and I sold the boat just to get rid of that motor. I blew up just up the ICW from Power Marine and it was classic being towed in by Dale with the cowling off and chunks of the motor everywhere for the crowd to see!!! I was told they just didn't have many problems with these motors that they sold....ironic all I see coming out of there now are Verados!!! I will say they were very helpful with my problem motor I just wish they had jumped ship before they sold me my POS. Greg
Scott- Everytime I read your posts I cringe. You have a fine boat there I just can not believe the bad luck you have had with it. I hope you get it all straightened out soon the Tuna fishery and Fall run are right around the corner for you.....
NewMoon you think this was bad check out the latest on the boat. This is why I can't bag on Yamaha, I still think my problems started the moment this motor arrived at Hydrasports door.
Here is my whole beef with Yamaha. They had fowling problems with the 250's right out the gate. Then the #2 and #4 cylinder issues. To make matters worse they let the 300's out with an even worse plug fowlling issue. This tells me they don't care about their end user, they just want to be first to market. I don't own a Contender, but they blamed the blown powerheads on those boats on the livewells spraying salt water in the cowling while running. However, they continued to market the moters on the boats. It wasn't until users started putting on verado's that they had "a fix for the air intakes on the cowling". I don't know about you all, but I'm tired of a "fix". I want it right the first time. If they don't get me right this year, you'll see a new emblem on my boat. It will be named "Ask me why" then it will have YAMAHA with a big ghost busters emblem around it. Oh, I guess I should mention Yamaha's new color I will be sporting, bright yellow with a lemon for an emblem. Maybe that will at least turn a few heads in Biloxi if nothing else. So if any yamaha guy happens to read this. Here is my request, a fair buy back of the motors for the new f250's or extend the warranty and pay my ride in a tourny for each failure of the motor. Sounds fair to me (181 hours 4th powerhead) Now at hour 200, getting close to new powerhead time, maybe 2 or 3 more trips. So come on Yamaha what do you say?
fish, I think they are going to have to offer a buyout. I went to pull my boat tonight and holy shi* is it rough. It was bad enough people were clearing out of the way because they thought I'd crap out in moving the boat literally 30 feet. That rough!
I hope it is the actual injector, but it's just as likely IMO it's some other component or wire related to it. Like I said, what's pissing me off is the motor was delivered running the same way 15 months ago, and now 15 months later and a new powerhead/break-in later, I'm right back where I started.
Fishinnant, when they say the grass is greener...just consider at least you can slap a new motor on your boat. I'm cleaning the fiberglass shards out of my arm as I type this from trying to put the pieces of my boat back together. Hell, if my HPDI had run at full steam all the time my boat would likely be at the bottom of the creek...it may have been a blessing in disguise.
Thats funny i had two blown engines in biloxi last year. You probably saw me there. It was a 39 midnight express with trip Yamaha 250 HPDI's. I have blown six with one more not even working out of the box. I two have told them that i dont want the fix anymore and have requested new engines. I think your only hope is two get legal aid. I'm sure some attorney out there sure could have a good class action suit if they wanted to take it on.
Just a side note. I posted a while back complaining of a sputtering engine at very low rpms. Also accompinied by a blown fuse for the ECU, if left to idle for to long. At speed there was a cutout every so often. Acting like fouled plugs, but not fouled plugs. My injector drivers and injectors were replaced. The problem did not come back, then the #2 cylinder went. Still only got 4.5 hours on the new motor, baby due in 4 weeks and work has been busy. Hope to get out again in oct after the baby is settled and able to travel to the river house. Striper season should be opening about that time. So far the motor has been good.
The very basics of mechanical intelligence require you to find out why an engine blew. Some dealers simply replace the parts and never bother to consider what caused the catastrophic failure. Engines do not come apart for no reason. Regardless of the year or make of your engines. If it fails to the point of requiring a new powerhead do not accept it back from the shop until they can tell you why it failed and show that the contributing part has been replaced. Sorry you guys are having to deal with this. It is way past time for a class action lawsuit.......
My 04 300 fouled its first set at 34 hrs, loast yr. Off season they adjusted the oil position rod.
At 45 hrs yesterday, it started the rough idle, then then later, refused to go over 4000 rpms (sounded if she was gonna die when you pushed it above). Did that twice trying to throttle up (albeit after about 30 mins idling around). Then she finally went full throttle, but has dropped a from 5500 to 5400 in a day.
........here we go again!!
__________________ Current:
19' Alcar cc
24' Grady White Explorer
...and a blow-boat to be named later
Scott, there has to be a fundamental design flaw with these engines. Just to many folks with them grendading. Like I have stated before a friend of mine had 3 powerheads come apart in one year. He now runs a yammie f250 and is fishing again besides becoming a marine outboard technician. On the bright side you may have another career in the marine business at this rate
Did someone mention a class action suit? Sounds like a good idea for the 250/300 hpdi owners. Yammy really screwed up on these motors. I thank God for my 2000 150 Merc, no problems except stator last month. That seems very minor after reading about the hpdi fiasco.
Man, after reading this thread I am glad I have my Evinrude FICHT's.
Seriously, I am sorry you guys are having so many problems with the Yamaha's. I know what its like to have a boat and not be able to use it because of engine problems. Anything else can go wrong on a boat....but when your engine does, your done.
It sucks to spend all that money on new stuff and have problems with it. I am sorry your having to deal with all that crap. Good Luck to you guys and let us know how it turns out.
__________________ John McGinty
Hydra Sports 26
O-SEA-D
Boys, I have to give you the latest from Yamaha corporate. It will not apply to most users on this tread but it will still affect some. I asked James Mills a serious question about the oiling on the 250's and 300's and the answer was not good. I asked him if all of the problems with the 250/300 block was usually due to lack of oil or water intrusion, then what would happen if I put my boat up for the winter (2-3 months) without starting it and went to crank it a the beginning of the fshing season. He informed me that if I was going to store the boat over 4-5 weeks I needed to winterize the block by fogging it so that oil would stay in cylinders. If not, you could get hit with a double whammy, no oil in the cylinder a start up and condensation rust that would damage the rings. He recommended at least cranking the engines every month regardless. I sure do miss the simplicity of a carbed outboard. It seems like the reasons for purchasing an outboard in the first place(less weight,less maintainance, and lower cost) is coming to an abrupt end. I/O's are starting to look good again to me.
250 HPDI/300 HPDI Powerhead Replacement Bump 
