Throttle Body Cleaning

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RossKean

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The '07 with 185,000 miles has been running a bit rougher than it has in the past so I figured it might be time to FINALLY get around to cleaning the throttle bodies. I expect to be selling the bike in the next month or so and I would like to have it running nicely. In looking for advice, I came up with THIS thread.

In Post #7, wfooshee gives a nice description of what has to be removed:

Seat off. Tank off. Fuel rail off. Side bodywork off (but not the main fairing panels.) Remove the air filter and unplug the ECU. Remove the tool tray (which the ECU is bolted to.) Unplug that sensor that sits on the airbox, and remove the bracket that holds the back of the gas tank, since it also holds the top of the airbox. There are several hoses to the airbox, including one underneath that you won't find until you lift the airbox and wonder where it came from, unless you're looking for it. So look for it.

That was for a Gen I, any significant differences for a Gen II that I need to be aware of?

I'm sure major differences will quickly become apparent but I hate surprises!

While I was at it, I figured I would:

  • Clean up any electrical connectors I encounter
  • Shoot some lube into the throttle cables
  • Clean out the airbox
  • Squirt some Seafoam through the throttle body sync ports
  • Light lube (silicone spray) of mechanical bits, pivot and linkages? (or will the lubricant become a dust magnet?)
  • Any need to do anything with the fast (cold) idle stuff? (no issues so far)
  • Will have a good look at the fuel injectors and may give them a quick buzz in an ultrasonic tank
  • Throttle body sync
Anything else?

Also, Fred W posted some nice photos in that thread. It appears that each of the throttle plates is held on with two Philips (or more likely JIS) screws. I was thinking it would be much easier to clean them if they could be removed from the assembly. In the picture from the back side, it appears that the ends of the screws have been peened. Anybody know for sure? Might be able to be removed and replaced but might not remain secure. Perhaps just leave well enough alone. See Fred's pics, below.

https://i916.photobucket.com/albums/ad4/FJWinNH/FJR1300%20Modifications/Throttle%20Body%20Cleaning/100_4470.jpg

https://i916.photobucket.com/albums/ad4/FJWinNH/FJR1300%20Modifications/Throttle%20Body%20Cleaning/100_4474.jpg

 
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Don't remove the throttle plate screws!!!!. If you are removing throttle body assy just clean it that's it. Avoid anything that eats rubber part from excessive over spray.

Injectors are electrical parts don't put them into a fluid.. Run some fuel injector cleaner through tank that's all for them

TPMS is at end of throttle body. Don't get any cleaner fluid in there either.

 
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Don't remove the throttle plate screws!!!!. If you are removing throttle body assy just clean it that's it. Avoid anything that eats rubber part from excessive over spray.
Injectors are electrical parts don't put them into a fluid.. Run some fuel injector cleaner through tank that's all for them

TPMS is at end of throttle body. Don't get any cleaner fluid in there either.
Thanks for the reply! I haven't gotten in to this before so the advice is appreciated!

Throttle plate screws - That's why I posted Fred's pictures. I thought it might be a bad idea so I wanted to confirm. It WOULD make the cleanup easier!

I was going to use carb cleaner on anything metal, but with care - the stuff isn't very good for rubber, some plastics and paint! Maybe the Seafoam Deep Creep might loosen stuff up to make mechanical removal easier.

Injectors - I wouldn't dunk them, just dip the tips into solvent based cleaner. I suppose that without a means of activating them during the process, there isn't much point. It would be nice to be able to remove the inlet screens to sonicate them but someone (dcarver, I think) mentioned that it couldn't really be done without destroying the screens. May talk to someone local who may do fuel injector service while they are out of the system anyway.

Is there anything in the throttle body sync ports that would be damaged by a cleaning solvent? I was just thinking that any deposits or dirt might make a stable sync more difficult to achieve. Obviously, it would have to be fully dried before reassembly.

I had neglected to add the TBS to the end of the process. I edited the original post while you were posting your response.

You mention TPMS is at end of throttle body. Don't get any cleaner fluid in there either What is TPMS - throttle position sensor?

Edit to add:

I am an analytical chemist by trade. I am going to try to get a large enough sample of the crud to analyze and determine whether it is oil, carbon, fuel residue or "dirt" that made it through the filter. (or a combination).

 
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Yeah. TPS. Don't worry about injector screens unless tank or fuel had a issue. Rust ETC. Screens are very fragile and will most likely break if you try and remove them.

Never removed sync port screws but I'd bet there is a O ring in there.

I have a 07 throttle body and injectors from a engine replacement I'll look in on SAT. Have a few car maint. things to do first.... Try to post later on SAT.

 
No known issue with rust, tank or fuel other than the fact that it has had something on the order of 4500 gallons of gas through the engine (over 1000 gallons squirted through each injector). How much insoluble particulate in that volume that didn't get picked up by the screen on the fuel pump? It is amazing how few major problems we have with these things!

Let me know what you find on the throttle body sync ports. I might not get to it for another week or so anyway...

Thanks

 
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People who send their injectors off for cleaning report that the bike runs awesome when it's back together. Carver sent his off somewhere. Had them back quick, and if I remember right, about $22/injector or something like that. For $100, I'd definitely let someone else do that.

 
People who send their injectors off for cleaning report that the bike runs awesome when it's back together. Carver sent his off somewhere. Had them back quick, and if I remember right, about $22/injector or something like that. For $100, I'd definitely let someone else do that.
I may see if I can get them done locally. A generous forum inmate offered a swap of my old injectors for refurbed ones so a wait wouldn't be necessary but cross-border parts exchange could take some time! Will check out local sources to see if I can get it done here. I agree that if it can be done for $100, it would be worthwhile.

 
Ross,

It wasnt that hard to get those ugly looking throttle plates clean by just spraying. The stuff that is caked up on them easily dissolves when sprayed with solvent. Dissassemble as little of the assembly as possible. If the high idle circuits are working now, dont F with them.

My strong recommendation is to avoid using carb cleaner entirely. Counterintuitively, that stuff is too rough on internal rubber parts for use in an assembled throttle body ( or carb for that matter). Instead use brake cleaner spray. It is just as good at cleaning but wont soften the rubber bits.

The job was tedious, but not difficult. The hardest thing was getting the throttle port boots fully reseated during reassembly

 
I may have to pick up some "new" brake cleaner. I think the only can I have contains the good old chlorinated solvent formula - available until fairly recently (at least in Canada)! Chlorinated solvents are even harder on rubber bits than the light ketones in carb cleaner and they do not evaporate out of the rubber as quickly - great cleaners and degreasers, though!

As far as I am concerned, the bike runs well but is just a bit buzzy. Since I will be selling (or gifting) it, I wanted to do some housekeeping stuff that the new owner may not be able to do.

With respect to the fast (cold) idle circuit, my inclination was also to leave well enough alone. I only remember forum references to one instance of a gummed cold idle circuit - Radio Howie a few years ago. Thought I would ask...

 
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