[08Bonnie]

Three weeks ago I parked my carbed 08 Bonnie after a nice ride with some mates. She was running great, not even a hint of anything wrong, ever. Two weeks ago I went to start her up for a quick ride and she wasn't having any of it. Sounded like crap, almost like it was firing on one cylinder, when I try to give a little gas it runs worse and then dies.

After some long searches on the forum, I see that it could be a spark issue or a fuel issue so I start checking the spark side. Both cylinders get hot so I know they are both firing. I checked for spark on both and it is good, (changed the plugs just in case anyway). Both spark plug wires measure fine. Dumped the old fuel out and replaced with fresh fuel, no better. Changed the coil, no better. Cleaned the inline fuel filter, no better. Started the bike and sprayed starter fluid onto the carb filters (which by the way I cleaned and are as new) and no difference. Checked the carb floats, slides ect., all look in excellent condition. No rodents in my exhaust. I even borrowed a friends Ignitor and tried it on my bike but alas, no improvement.

So tonight I took the carbs off and took a peek at the valves. Now I am not a mechanic, but something tells me that built up tar-like material on your valves is not good. This stuff looks like oil and I have never seen anything like it. Could it be coming from the cylinder head? Maybe from the radiator pumping into the cylinder head and then down onto the valves? I cant imagine this would have happened as a matter of normal running, even if I was running very rich. I know I was not running rich bc my dyno run confirmed this.

Has anyone seen this before or have any ideas what could be causing this? You can also see from the pictures that this stuff has found its way into the carbs. It is sticky and to me looks like it could be oil. Both sets of valves that I can see look exactly the same so I only loaded one picture. So, what is it? How did it get there and what can I do to fix it?

Any ideas would be great. Thank you.

 

[clydeturbeaux]

How many miles do you have on the bike? Is it using (burning) oil?
When was your last valve adjustment? What type of oil are you running? Is it overfilled?
I wouldn't think worn valve guides or seals would happen until many, many miles are accumulated.
Could it be fuel deposits?
Have you checked the compression?
Maybe some of the more experienced mechanics could chime in here with some thoughts...
Dr. Forchetto? Paging Dr. Forchetto...

 

[Aussie_T100]

Bad blowby resulting in heavy oil deposits in the airbox? (sounds like you have pod filters so this is likely ruled out).

Over oiled aftermarket air filter(s)?

An overdose of fuel additives?

Contaminated fuel?

Whatever it is it is most likely coming from upstream of the valves as you say it is present in the carbs. It is highly unlikely that any oil getting into the intake ports, such as through leaking valve stem seals, is going to work its way back upstream as far as the carbs.

 

[denbow]

The last time I saw valves like that was after somebody sugared the fuel.

 

[mightydaj]

A short while ago my 07 carbed Bonnie started running poorly espically at slow speeds. I most likely let some ethonal gas sit too long in the carbs. Carb cleaner added to the gas tank helped some but not completly. So I pulled the carbs and soaked them in one of those carb cleaner pails that look like a paint can and cleaned them out real well. While the carbs were off I looked down the intake tract and saw it was coated like your carbs look. The valves were simular to the way yours look also. I cleaned the intake tract with the cleaner but did not attempt to clean the valves, to hard to get to and was worried I would knock chunks loose that would go down into the cylinders. I don't know what causes it but am hoping it is left over from when I had the air box on, now I have pods. Since then I have been adding carb cleaner to the gas at every fill up in the hope that it will eventually slowly clean the gunk off of the valves. After putting the carbs back on the bike it runs very nicely as before, so the cleaning worked. The gunk on the valves has probably been there for a very long time and I can't tell any if it is hurting performance any, but it can't be much if at all.

 

[RICHW]

The last time I saw valves like that was after somebody sugared the fuel.

Hmmm... do you have a locking fuel cap? Those pics don't look good...

 

[cdubya]

The last time I saw valves like that was after somebody sugared the fuel.

Eeeek! Man, I hope not. If so I suppose it's time for a tank/carb bath. On the note of people doing sh**** things to others that I have experienced this year:

*Pried the Dodge Ram emblem off of my old beater of a truck's engine hood probably to wear as jewelry. ????? Punk kid maybe.
*Stole everything out of our company Suburban which included my roller bag suitcase containing my clothing for the work hitch. Probably a crack head....I'm watching for a crack head wearing my beloved Triumph T Shirt.

I digress... Sorry for the ramble 08Bonnie. If I weren't on the other side of the country I'd gladly spend a day helping you tear her apart and clean 'er up! Carb cleaner and Seafoam plus a full day of elbow grease, she'll be right.

 

[08Bonnie]

Some details that were missing:

Bike has 11,500 miles and has never had a valve check or adjustment. I've been running pods for a couple years, no airbox. When the bike is running absolutely no white smoke or otherwise can be seen from the exhaust. I may have overfilled oil slightly but never over the upper hash on the site glass. I don't think I was running rich as my dyno confirmed about one year ago. Never used fuel additive in the past.

Brought my carbs and pictures of valves to my dealer this am. They said that it is most likely deposits from fuel and not oil. Suggested I use seafoam and fuel additive to clean up valves. I went and bought both and have begun the treatment. It seems to have helped a bit but still a long way from running right. Maybe I need to go through the entire can of seafoam. With the condition of my valves i find it incredible that anything other than a good scrubbing will be able to remove the buildup but I guess this is my only route at the moment. If I can get the bike running well enough to limp up to the dealer I am tempted to let them have a once over. Time to check valve clearances anyhow.

I appreciate very much the replies.

 

[kartooo]

back when i had an fjr1300 and a member of that forum i saw and read that happened there a few times. it was blamed on fuel additives and would actually make a valve stick in the guide and crash into a piston on compression stroke. it was always out of state after a fuel up and a highway run. my son-in-law works at a toyota dealership and has seen it a few times too with valves gummed up like that and stuck in the guides. big $$$ mess. check your compression. you could have a valve hung up/not sealing. i belive in seafoam every few tanks.

 

[mikeinva]

get some spray carb cleaner and clean as much of that mess up as you can.bad valve seals can cause the oil on the valves .I would start by checking comp to make sure nothing broke in the motor .If its missing they do spit back through the carbs.That could be the mess in the carbs.But they allso do that when they blow up.If you can get it running good the oil on the valves isnt that big a deal alot of them do that. What do the spark plugs look like?

 

[kartooo]

been searching around the net doing some research on gummy valves. seems like old ethanol gas is the popular cause. found lots of pics of valves that look just like yours. here is just one of the links;
http://www.williammaloney.com/Misc/EthanolProsConsDrawbacks.htm

 

[08Bonnie]

get some spray carb cleaner and clean as much of that mess up as you can.bad valve seals can cause the oil on the valves .I would start by checking comp to make sure nothing broke in the motor .If its missing they do spit back through the carbs.That could be the mess in the carbs.But they allso do that when they blow up.If you can get it running good the oil on the valves isnt that big a deal alot of them do that. What do the spark plugs look like?

Thanks for chiming in Mike.

I spent an hour or so adding seafoam spray directly to the valves through the little inlet (one with the black cover on it) this morning. I thought things were getting better, and as the engine warmed up it was firing a little better I thought. Then this eve I went out to try again and now both cylinders are blowing back so hard through the carbs that the carbs are getting knocked off their boots. I can't even keep the engine on for more than a few seconds that this happens. Why is it hissing and firing back like that? Never heard or seen anything like it. At this point I dont know what else to do. I'm afraid I've done more damage with the seafoam but I dont know how I could have.

The real kicker is that three weeks ago I parked the bike after a really nice ride and the next time I went to ride it this big mess happens. Feeling very frustrated. What are my options?

Kartoo, my valves pretty much look just like those. It got me thinking how many others have valves that look similar to mine.

 

[Durbud]

Been running seafoam every 3 or 4 tanks on both bikes, so good so far. Knockin on wood.......

 

[JustPete]

Thanks for chiming in Mike.

I spent an hour or so adding seafoam spray directly to the valves through the little inlet (one with the black cover on it) this morning. I thought things were getting better, and as the engine warmed up it was firing a little better I thought. Then this eve I went out to try again and now both cylinders are blowing back so hard through the carbs that the carbs are getting knocked off their boots. I can't even keep the engine on for more than a few seconds that this happens. Why is it hissing and firing back like that? Never heard or seen anything like it. At this point I dont know what else to do. I'm afraid I've done more damage with the seafoam but I dont know how I could have.

The real kicker is that three weeks ago I parked the bike after a really nice ride and the next time I went to ride it this big mess happens. Feeling very frustrated. What are my options?

Kartoo, my valves pretty much look just like those. It got me thinking how many others have valves that look similar to mine.

You're washing the gunk into the engine. It can end up on the valve seats keeping the intake valves from completely closing causing what you describe.

They do sell top engine cleaners but it's still washing it into the cylinders. Blasting the valves with ground walnut shells works the best but you need the right equipment and knowledge before attempting.
Check locally to see if a dealer/shop has the equipment and experience to use this system. It only takes minutes and the valves will look as new, it uses an extraction system so nothing enters the cylinders, valves must be closed. Again, experience and knowledge before attempting this.

 

[Wheelhorse]

Have you performed a simple compression check yet?

 

[kartooo]

i think the goo is stopping your intake valves from closing. either some on the valve seat or valve giude making them hang up. your compression is exiting your intake port !!
Forchetto, what % of ethanol are they forcing on you over there accross the pond ??

 

[08Bonnie]

Have you performed a simple compression check yet?

I have not. Does this require special tools? It makes sense that if the valves are not closing all the way on compression stoke that this is getting blown back and knocking the carbs off their boots. So, ideally, what would be the best way to proceed? Take head and valves off? That would be new territory for me.


Sent from my iPhone using MO Free

 

[Aussie_T100]

bad valve seals can cause the oil on the valves .

When the bike is running absolutely no white smoke or otherwise can be seen from the exhaust.

Valve stem seals that are far enough gone to leave oil deposits like that on the valves would surely result in some exhaust smoke, at least on start up. Wouldn't you agree Mike?

With the absence of any exhaust smoke I'm thinking some sort of fuel contamination has to be the explanation for this?

 

[Forchetto]

Forchetto, what % of ethanol are they forcing on you over there accross the pond ??

None over here yet, but EU Directives are in place to achieve 10% ethanol consumption by 2020.

 

[kartooo]

I have not. Does this require special tools? It makes sense that if the valves are not closing all the way on compression stoke that this is getting blown back and knocking the carbs off their boots. So, ideally, what would be the best way to proceed? Take head and valves off? That would be new territory for me.


Sent from my iPhone using MO Free

it does take some know how to dig into a job like that. valve spring compressor,torque wrench etc. for tools. most common problem jobs are well documented on the net with step by step pics. i would buy/borrow a compression gauge 1st to see where you stand. maybe let the seafoam soak in for a while to possibly soften that goop up.
my late Boss had a saying "don't want to cut off your whole foot when there is only something wrong with your baby toe" what would bother me is if one of your intake valves get stuck open enough your piston will crash into it on the compression stroke !! if your not pressed for time it is doable for a brave novice with common sense. the cost of tools and gaskets should'nt be too bad. once the head is off you could just take it to the local machine shop. if it was my bike i would have the head off already if the compression was way off. i have been there many times with both bikes and car engines. the bonnieville looks pretty staighforward in design and i think the head will come right off with out removing the engine from the frame.