Yamaha V150J Carburetors parts & Troubleshooting help!!

[dragnfli]

I have a 1986 Yamaha V150J starts and runs ok, but does flood a bit. Main problem the motor will not plane out or get above about 10MPH.... All indications show gummy Carbs. Took them off and sure enough they are major need of cleaning. However when I took them off I found more of a problem. See first pic, a piece inside had broke off. What I noticed is that side looked fairly clean, but the other inlet side had a lot of build up. See second pic. The third pic is of the back side, you can see how much build up the opposite side has of the piece that had broke off.

Questions:

1. Can someone explain why the extra build up on the opposite side?
2. Is there anywhere I can get the replacement part for this?
3. I also need the replacement screws that were in the rod that when through the carb.
4. When I took this apart, after I pulled the rod out a very small spring appeared on my towel....I can not find where this thing came from, see last pic. Please help. The rest of the carb has also been dis-assembled.
5. Any tips and tricks for cleaning these carbs would be very helpful.

Thanks so much for everyone's help.

Po boy needing to go fishing .

[boats.net]

Need to do a compression test to make sure none of broken choke plate got into engine and damaged piston and cylinder. Need to remove intake and check for broken reed valves and look for any broken pieces inside crankcase.
The choke plates are not available, would need to replace carb.
Those two cylinders are not running even, could be due to dirty carbs or have engine damage.

[dragnfli]

Thanks for the info, I will check the reed valves and compression tonight. I did look over the reed valves, but did not take them completly off. All looked fine, but I woudl expext I need to take them off to make sure.

Good news was the one pc. that broke off fit back on perfectly and I could not see any missing pcs., but something really small of course could be gone.

Let's say reed valves check out, compression is good. The carbs where way dirty, I cleaned them and they appear to good to go. What would the negative impact be if I do not replace the choke flap? Seems like it woudl not choke that one carb, but all in all it should still run fine?

Thanks for your help.