#4 Cylinder Foul Out Fixed-Alas

Just got my '03 back from the shop last week and should put the #4 cylinder fouling problem put to rest. Come to find out after getting the supposed ticker fixed with a new head in June, then replacing the valves/valve guides & seals with the Updated type in November, it still fouled out #4 cylinder, had low gas mileage, and used oil.

Come to find out, after intense inspections/testing, it is suspected the #4 cylinder was ovalized allowing oil to bypass and causing High HC levels measured at appx 2200 when normal is about 300. So Yamaha approved replacing the engine cases, pistons, rings etc. under the Y.E.S. Warranty , to fix this very unusual problem that has been giving me grief for almost a year.

It is a no wonder I could not stablilize the tune ups and kept getting erradic behaviors.

https://www.fjrforum.com/forum//index.php?s...st&p=257350

https://www.fjrforum.com/forum//index.php?s...st&p=271113

https://www.fjrforum.com/forum//index.php?s...st&p=335578

I am TRULY Grateful to Yamaha/Steve Hamilton/Regional Techs/ & Motions for getting Silver back to normal shape.

Now for some nice weather so I can really have some peace of mind with this magnificent machine.

A Salute to All for a Great '08!

03HiYoSilver said:

Just got my '03 back from the shop last week and should put the #4 cylinder fouling problem put to rest. Come to find out after getting the supposed ticker fixed with a new head in June, then replacing the valves/valve guides & seals with the Updated type in November, it still fouled out #4 cylinder, had low gas mileage, and used oil.
Come to find out, after intense inspections/testing, it is suspected the #4 cylinder was ovalized allowing oil to bypass and causing High HC levels measured at appx 2200 when normal is about 300. So Yamaha approved replacing the engine cases, pistons, rings etc. under the Y.E.S. Warranty , to fix this very unusual problem that has been giving me grief for almost a year.

It is a no wonder I could not stablilize the tune ups and kept getting erradic behaviors.

https://www.fjrforum.com/forum//index.php?s...st&p=257350

https://www.fjrforum.com/forum//index.php?s...st&p=271113

https://www.fjrforum.com/forum//index.php?s...st&p=335578

I am TRULY Grateful to Yamaha/Steve Hamilton/Regional Techs/ & Motions for getting Silver back to normal shape.

Now for some nice weather so I can really have some peace of mind with this magnificent machine.

A Salute to All for a Great '08!

Click to expand...

03HiYoSilver,

Great to hear!!

Ride that silver bullet safe now YA hear!!!

WW

Glad to hear they figured it out, and kudos to Yamaha for stepping up in a big way under warranty.

Looking forward to an explanation of what might cause that "ovalizing". Jestal, you here??

Boy, this is looking sort of deja-vu-ish. . . . Silver, you may recall my thread with a misfire resulting from a fouled #4, and producing a weird rattle when the idle dropped on the misfire.

Well, #4 still fouling. It's very black, but to be it looks sooty, not oily. What do I know, though, I need 2.5 reading glasses to see anything close enough to touch. I've got standard plugs in it since that time, and I've taken to "rotating" the plugs when the idle gets rough. Pull #4, clean it, and swap it with one of the others. The good cylinder cleans that plug, and the good plug goes to its plug hell in #4 for a couple of weeks. Like you said about yours, mileage sucks: low 30's in town, barely over 40 on the road. I unhooked my Power Commander thinking it was possibly bad, but only a slight improvement in mileage.

The bike was better after I ran a couple of tanks with Seafoam in the gas, and the exhaust outlets aren't sooting up as much, so maybe I need a good serious injector cleaning or a new injector for #4.

I am the second owner, no Y.E.S. and I have no records from the previous owner. He keeps saying he can send them, but I've given up. Also, he tapped the engine mounts that you use for sliders for an SAE bolt, apparently he had some Harley highway pegs there. Ya think Yamaha's OK with that? :glare: (I discovered that when I bought my sliders and the metric hex key didn't fit the mount bolt. He had put hex-key bolts in there, but they were 1/2" 10-24 with a 3/8ths head, so at a glance, they looked right. Had to go buy bolts for my sliders and put the aluminum sleeves on the drill press to get them to 1/2" I.D.)

The dealer here in Panama City is so bad that my insurance company wouldn't use them for new plastic after my low-side in October, offering to take the bike up at their expense to Dothan. (I had them just pay me for the plastic and put it on myself. They even paid me the labor, so I got paid to fix my bike!) Atlanta's not THAT far away, but a bit of a trip to go and say, "Hey, I think my bike's got the same illness that you saw on another '03." I have no Rivnuts installed.

And . . . . . my wife is changing jobs, so there's not a lot of spare change lying around. I can't take it somewhere and have them tear it down only for Ymaha to say "no" to whatever it is. Even if Yamaha says "OK" I don't know what portion of the job they'll cover and what I have to pay for, parts- and labor-wise, but it can't be much right now. Maybe I just give up and buy an eBay motor. . . .

Thanks for all your kind remarks and support.

It has been a long and tedious year and thought this may help someone and Especially share my Appreciation with this board and the Dedication/Quality of Support with YAMAHA.

I have not heard of any other manufacturer that back their products like Yamaha and I am proud to own them.

I say sell it and get another one that a harley rider did not own

You are going to have one problem after another sell sell sell

03HiYoSilver,

Great to hear!!

Ride that silver bullet safe now YA hear!!!

WW

Thanks! I will... it sure is nice to have my respit back.

exskibum said:

Glad to hear they figured it out, and kudos to Yamaha for stepping up in a big way under warranty.
Looking forward to an explanation of what might cause that "ovalizing". Jestal, you here??

Click to expand...

Yes I am grateful. The Top Regional Tech did not offer any explanation and I did not get the parts to look at for comparison. They all were scratching their heads.

Not sure if carbon got in the chamber and scratched the cylinder wall or what. Even more interesting, is that the Leakdown Test and Compression test on the #4 cylinder were within specs ... makes it even more mysterious.

If I ever find out some more details, I'll let you know... but definitely a fluke with this well engineered motorcycle.

That's great Silver! Sure looks like Yamaha stepped up big time on this one. Yamaha also took real good care of me when my ignition switch failed 1000 miles from home.