Dirt in Carbs?

[krusty]

I forgot to mention that I haven't drained the carbs but I did run the engine with the tank off for a while. I've read about lowering the frame so I'll keep that in mind if I have problems. looking like its the 1100 for this Sundays' VJMC fish and chip ride to Patonga.

[movenon]

Just unbolt those 2 large side bolts on the rear sub frame, unbolt the bolt on top of the air box and rotate the rear sub frame down. Finish unbolting that air box and remove the box. Only takes a few min and makes it a lot easier to remove and install the carbs. Forcing them like in the video IMO increases the chances of damaging parts. 

Note on your mixture screws be careful each screw has an spring, O ring and a washer.  Easy to loose the very small washer and or the O ring. 
George

[FJ_Hooligan]

Spray some carb cleaner in those holes and follow that up with compressed air

[Harvy]

  Krusty,
I didn't notice any mention of draining your float bowls. I would.Also,before you go to all the bother of carb r&r, it's simple to remove the mixture screws, the springs washers and "O"rings (After you've made sure to clean off the carb tops) A good shot of compressed air down each hole is often effective in clearing out the pilot jets.In the hundred times I've done this it has never caused any damage to a carb diaphram.   If you do remove the carbs, you do know that lowering the rear subframe makes the job easier, right?
 
Harvy
The heat range is the 8, after the D.The -9 refers to the gap or tip design. At least that's what  NGK would have us believe.

Correct Simon.... my mistake:

http://www.ngk.com.au/spark-plugs/product-information/part-numbering-system

Cheers
Harvy

[krusty]

Just unbolt those 2 large side bolts on the rear sub frame, unbolt the bolt on top of the air box and rotate the rear sub frame down. Finish unbolting that air box and remove the box. Only takes a few min and makes it a lot easier to remove and install the carbs. Forcing them like in the video IMO increases the chances of damaging parts. 

Note on your mixture screws be careful each screw has an spring, O ring and a washer.  Easy to loose the very small washer and or the O ring. 
George

That's nicely explained, sounds much simply/easier.. I'll give that a go if the compressed air fix doesn't work.

[krusty]

Just unbolt those 2 large side bolts on the rear sub frame, unbolt the bolt on top of the air box and rotate the rear sub frame down. Finish unbolting that air box and remove the box. Only takes a few min and makes it a lot easier to remove and install the carbs. Forcing them like in the video IMO increases the chances of damaging parts. 

Note on your mixture screws be careful each screw has an spring, O ring and a washer.  Easy to loose the very small washer and or the O ring. 
George

Managed to extract all those little bits without losing any.

[krusty]

Went to Supercheap this morning for their 20 percent off sale which ends today. Bought 4 x DPR8EA-9 and 4 x D8EA for $3.99 each. The D8EAs are for my CB750.
I happened to notice the fuel filter attached to the bottom of the tank. Do they have an auto equivalent of do I need OEM?

[movenon]

Went to Supercheap this morning for their 20 percent off sale which ends today. Bought 4 x DPR8EA-9 and 4 x D8EA for $3.99 each. The D8EAs are for my CB750.
I happened to notice the fuel filter attached to the bottom of the tank. Do they have an auto equivalent of do I need OEM?

On the fuel filter I would recommend the stock Yamaha filter. Been down that rabbit hole. In this instance because of it's location under the tank and on top of a hot engine I say don't risk using an adapted unit.  There are the hose fittings and also some of the auto filters appear to use a pretty thin plastic shell that may not hold up well under heat.  I am all for cutting costs but on this one I say use a stock Yamaha filter.   Its not like anyone replaces it every year. I bet there are some many years old still working in the bikes. Some owners are not even aware there is a fuel filter there (only applies to the fuel pump models 88-93)
George

[Earl Svorks]

  Krusty,
You may  be wise to this already, another reader may not.
  A good dab of your favorite grease will serve to hold all them little bits on the pointy screw when you put them back into the carbs.  The grease will make installation easier. It will also help prevent seizure of the screws into the carbs. The little rubber bungs Yamaha installs at the factory often seem to go missing. If they are absent, without grease water will accumulate in the bore. I have had some real struggles with mixture screws that were seized in the carb. Ya' don't wanna' go there.

[krusty]

I believe an update is due.
I have removed the pilot screws. Blue-Tack worked well for that and some fine copper wire hooked out the spring, washer and O rings that didn't come out with the jet. Using a syringe I injected some Wynnes injector and carb cleaner in the pilot jet holes then left it for a while. Later on I used the compressed air as previously suggested. I'm not going to pull the carbs, just yet. I then put everything back together.
When this problem first raised its ugly head I had only ridden the bike a short distance so' today, with Australia Day holiday long weekend out of the way I decided to take it for a longer run, give it some berries, and with any luck possbly blow the problem away. Wishful thinking? Yep.
First off, when I went to start it fuel was running out onto the floor - I'd forgotten to do up the drain screws. I blame 'Old-Timers' for that. Fixed it and then started it up. Fired and ran first go on half choke.
So off I go down the street headed for the Pacific Highway out of Swansea. After a couple of ks I could shut off the choke but had to keep the throttle on a bit to stop it stalling. Pulled over and adjusted the idle screw so that I could get close to an idle without it cutting out. Made it through Swansea and onto the highway proper, 100kph limit, and wound it out. It went like an FJ should. Accelerates as normal and no problem sitting on the speed limit. Ran it up and down through the gears and rpm range. Cruised into the little historic mining village of Catherine Hill Bay which is about 10ks from home. Then rode back to Swansea turned around and back to catho bay again. Back to Swansea.

https://www.google.com.au/maps/place/Swansea+NSW/@-33.0899591,151.6169469,14z/data=!3m1!4b1!4m2!3m1!1s0x6b7323df69e4aaa7:0x5017d681632f4f0?hl=en

Swansea, at the entrance to Lake Macquarie, has an opening bridge across a channel from the lake that runs to the Pacific Ocean and the bridge was up, to let cruisers and yachts in and out. The bridge was up and there was about a 400 metre, double lane queue of traffic waiting. I was able to filter between the staitonery cages to the front without problem but while waiting for the bridge to close the engine was constantly threatening to stall.
A few minutes later I was home and the miracle I was hoping for had not happened. The bike won't idle. I checked the idle adjusting screw and found I had wound it all the way in. It's looking like these carbs are gonna have to come off.
All this time I've been wondering why this has occured so suddenly. Considering the fuel is filtered before it enters the carbs. I drained some from the tank and it looks clean, even when I ran it through a tissue filter into a jar (grabbing at straws). There's no water contamination evident.
Situation now is I'm giving the carb cleaner and compressed air one more go and if that's not enough there's nothing left but to go into the carbs.
BTW, the new plugs are in.
Another VJMC ride last |Sunday,  250klm of fun on the 1100.

[movenon]

Please forgive the dumb questions.  Did you remove the pilot jets and then clean them or just wash fluid down the holes ? They need to be removed to get them clean. We are talking pin head diameters here in the pilot jets so it takes almost nothing to plug one or more up.   You didn't mention anything about syncing the carbs or how you adjusted the fuel air screws.
George

[krusty]

Please forgive the dumb questions.  Did you remove the pilot jets and then clean them or just wash fluid down the holes ? They need to be removed to get them clean. We are talking pin head diameters here in the pilot jets so it takes almost nothing to plug one or more up.   You didn't mention anything about syncing the carbs or how you adjusted the fuel air screws.
George
[/quote
Yes, jets removed and cleaned. PO log book showed synch not too long ago. Before removing the airscrews I wound them in and counted the turns making a note of each in pencil on top of the card vac covers.

[movenon]

My advice is to set all the fuel air screws to 2 1/2 turns out and then sync the carbs.  If it improves then do some blip testing watching the tach. If you readjust the fuel air screws then re sync the carbs again.  You will probably have to adjust the idle as you work through the adjustments. Final idle should be around 1100 RPM.

The PO's intentions were probably good but better to set the base line yourself. "trust no one, demand proof"  .

You can build a tool to sync the carbs cheaply if you don't have a commercial tool.  IMO anyone that owns an FJ should have one.
George

[krusty]

All the PO's servicing and tuning has been done by Yamaha dealer.
Interesting to note that air screws were set between 3.75 and 4.25 turns. I have a set of Honda vac gauges which I've used on my Honda 4s. Before this problem started the bike was running fine and very smooth.   

[movenon]

All the PO's servicing and tuning has been done by Yamaha dealer.
Interesting to note that air screws were set between 3.75 and 4.25 turns. I have a set of Honda vac gauges which I've used on my Honda 4s. Before this problem started the bike was running fine and very smooth.   

3.75 -4.25 is pretty rich. I would go down to 2 1/2 turns as a base line. Then sync the carbs. See if it improves things. Nothing like knowing for yourself.

George