Carb Cleaning Questions

SoulMan

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So I threw my carbs into the ultrasonic cleaner yesterday.

I bought this ultrasonic unit off of ebay:

https://www.ebay.com/itm/New-Stainless-Steel-10L-Industry-Heated-Ultrasonic-Cleaner-Heater-w-Timer/201970330204?ssPageName=STRK:MEBIDX:IT&_trksid=p2060353.m2749.l2649

I think they turned out pretty good. I used one part extreme simple green aircraft and precision cleaner to three parts water in the machine.

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In my haste to get them cleaned I took them apart really quickly... I think I am started to get a feel for how they go back together.

These are the components that did not go into the ultrasonic cleaner:

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I also didn't put the choke rod aka starter levershaft into the ultrasonic cleaner because of the plastic handle. I did put the starter plunger which is what the choke rod pulls out. I did notice there was a small seal on the large end of the starter plunger but it did not appear to be able to be removed:

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I didn't put in the plunger cap because of the plunger cap cover seemed like it was difficult to take off and I didn't want to break it or really deform it in the process.

Do you guys think that the little seal in the starter plunger would be fine after the cleaning? I hope so as that part 3F7-14171-00-00 seems to be in limited supply.

I am pretty sure I know which diaphragm goes into which carb based on where I put the diaphragms when I took them out of the carb bodies. But what I am not sure about is the butterfly plates. While it is probably best that they get put back into the right bodies I am hoping it isnt the end of the world if they don't :/ I can always swap them if I need to do so after the fact.

I see an o-ring, needle valve plate and pan head screw parts 24, 27, and 28 respectively mentioned here:

https://www.yamahapartshouse.com/oemparts/a/yam/50041ea9f8700209bc786903/carburetor

My carbs didn't come with those. Am I missing something? I was looking for any type of seals that should come out before I put them into the ultrasonic cleaner does it look like I missed anything?

Has anyone used these shaft seals from mikesxs with good success? I see people mentioning them in the forum but not much comments after the initial mention.

https://www.mikesxs.net/yamaha-xs650-seal-70-84-throttle-butterfly-shaft-oem-25-14997-00-00.html

What about this kit?

https://www.mikesxs.net/carburetor-...0-3l1-14190-20-25g-14107-00-3f7-14984-00.html

Will it work for our xs400s? Also that plug there... my carbs didnt have those... do I need them?

2018-09-07 00_20_37-Carburetor Kit - XS650 - 1980-1984 - Basic.jpg

Thanks for the help. I appreciate anyone taking the time to read all this :)

Scott

p.s. One last question. Anyone have a good tip of getting of that gasket that is left behind? I was using goof off but it was just taking a long time. Maybe that is what its going to take but thought I would ask anyways.
 
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Those carbs are off an 77-79 sohc xs400. You need to get parts for that model. Be very careful of the pilot mix screws as they will brake off in the carb bodies very easily. Replace the shaft seals with new ones. mikesxs has those.
 
Maybe because this 1980 was manufactured in 10/1979 ... Could that be why?

Fortunately when I took it apart the pilot screws came out fine without any issue. So happy about that. Thanks for the info... the exploded parts diagram for this carb definitely looks like it fits the bill.

When i go to put this back together how many turns do I set the screws that need to have something other than just tightened down slightly?
 
10/79 is late for an 80 model. My 79 was made 6/78. I would think at some point some one broke the 80 carbs in the bike and put a set of 77-79 ones in. I would try 2-3 turns out for mix screws. Lets hope someone has not drilled the holes out for the mix screws if they where broken off in the past. Those carbs also have adjustable jet needles. I would have them set at the third slot from the top. What size pilot and main jets does it have? I would start with 42.5 pilot and 135 main. Your pilot jets should have had screws over them did they?
 
My pilot jets did not have screws over them. How can I tell what size the pilots and the mains are?
 
Looks like your missing some stuff. The jets sizes are stamped into the jets.
 
Mine have 137.5 mains and 42.5 pilots in them. Thanks for the help. I will give them a try I guess... I dont have anything to lose :)
 
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