First time taking apart Carburetors (Lots of pics)

*This is under construction, as I am still taking these apart/cleaning them, so expect this to be updated frequently until completion

In this thread, someone with no mechanical experience takes apart, cleans, and re-assembles Hitachi Carbs from an '82 Xj750

I will have questions along the way, and hopefully others can learn alongside me

(It appears they are pretty clean already, as nothing has stripped or been hard to remove, but I have heard the good word at the Church of clean and will be singing the gospel over the next few weeks)



1.) From left to right: Carb 4-3-2-1 (exhast side, front of the bike)


2.)Back (airbox side) from left to right: 1-2-3-4

3.)From left to right: 2-1

4.)From left to right: 4-3

5.)Top: From left to right: 2 -1

6.) Top: From left to right: 4-3

7.)Airbox side (Back) from left to right: 1-2

8.)Airbox side (Back) from left to right: 3-4

9.)4-3

10.)2-1

11.)Sync screw between 2-1

12.)Sync spring and throttle cable holder between 3-2

13.)Sync spring between 4-3

14.)Taking the choke cable holder and carb hat off of 4

15.)All carb hats off. From top to bottom 4-3-2-1

16.)Sorry about this one (disregard the numbers): FROM LEFT TO RIGHT is 1-2

17.)From left to right: 2-1:

18.)4-3

19.)Looking at the float bowls: 1-2-3-4

20.)Carb hats and float bowls off (4-3-2-1)

21.)The inside of the float bowls

22.)Underside of the carbs

23.)Needles

24.)Drawing a diagram never hurts

25.)





26.)

 

Looking good, but why the Pump pliers/channel lock pliers??

 

Very thorough, especially the orientation of the throttle shaft closure springs and how their end tangs are oriented/aligned with the throttle shaft brackets and retaining "stubs" on the carb body........many people fail to notice that aspect during dis-assembly and then get stuck when trying to re-assemble them. Also note that on many carb sets, the springs on each carb are different from each other, even though you might be able to "shoehorn" a carb #3 spring, for instance, onto carb #1.......with Very Bad Results.

P.S. previous owner installed float bowls incorrectly.......bowls should always have their drain hole port facing towards the "outside" of the carb rack (so you can access both carb drain screws from the outside of the bike). So the two left-most carbs (#1 and #2) should have the bowls whose drain ports are angled to the left, and the two right-most carbs (#3 and #4) should have bowls with drain screws facing to the right.

 

Very nice, they do look really good.
For those who know better, why is the fuel inlet port between #3-4? On mine, admittedly a different bike (XJ700) the inlet was between 2-3, or rather it was right in the middle of the rack.

 

Maxim-X: I didn't actually use them to take anything apart. They were just laying around and I used them to keep the carb "level" for pictures

Chacal: I was so nervous to try all of this that I must have read carb posts on this site for three days beforehand. Splitting the rack was what scared me the most, and I knew taking a ton of pictures would be useful. Thanks for the tip on the carb bowls. I took the drain screws out last night with little issue. They are now completely apart and ready for cleaning.

Bigshankhank: Sorry, I cannot answer that for you.

The current condition really makes me think the PO took good care of this bike, because before I picked it up it sat outside untouched for a solid year and they look like this. Further, none of the bolts/nuts/screws were stripped.

Also, I didn't see that any of the passages were blocked, though I am curious about the one within the float bowl. I will know more tonight.

Now...to figure out if I want to use brake cleaner, carb cleaner, or boiling lemon juice to clean the insides out...

Then I need to figure out how I am going to get the exterior of the bodies nice and clean. The premise of this bike is to do everything myself so that I can acquire the tools, knowledge, and confidence to wrench on something I've always wanted. Therefore, taking these bodies somewhere to have them polished is not an option. Looking into ultrasonic cleaners at the moment...

More pics soon! I am taking this Friday night off from gallivanting around the city to get some bike work done.

 

Looking good. Imo lemon boil the bowls and soak the internals in carb cleaner (carb cleaner will eat through plastic). Source (dollar tree) a baker's muffin tin. Also source a good inexpensive air compressor (you'll need it). Those screws are called jis screws. They are not standard phillips. Flat file a phillips head screw driver to function like jis. Chacal also sells a jis set. You'll also need to file a standard flat screw driver to exactly fit the slot in the mixture screws. It'll make setting the screws after the rebuild a lot easier and more accurate. The fuel float valves/needles are different. The one with the open clip has a tendency to spin and get hung on the front of the float tang. It'll cause nightmares trying to figure out what's going on. On hitachi carbs the inlet for the fuel is usually located between #1 and #2 (other bikes may be different). Chacal sells everything you'll need for the rebuild. Hope this helps.

Gary H.

 

Or just replace ALL of the Phillips/JIS screws with Allen head screws and be done with it.

 

That ^ too.

Gary H.

 

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The fuel float valves/needles are different. The one with the open clip has a tendency to spin and get hung on the front of the float tang. It'll cause nightmares trying to figure out what's going on.
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yep, that's exactly whats happened on the 2 pictures of the floats, the needle retaining clip should lay across the float tang ,not over the end of it, when you put em' back together double check that bit
stu

 

that's the cleanest set of dirty carbs i ever seen !

 

Right!

 

We try to learn as much as we can while we're in there. Just so you know...in the pic of the float towers on the right side of the swing arm there is a bent tang. That is a "stop" to prevent the floats from dropping far enough to allow the valve/needle to fall from the seat. Make certain they're not buggered. Also the labeling is incorrect in the plan view schetch of the carb jets and throttle knob. They are labeled as if you're sitting on your bike (most left is #1). You'll be helping other new members with all of this in short time. Hope this helps.

Gary H.

@ stu: Good eye. I didn't see those clips until you mentioned them.

 

Thanks stu (and everyone else) will do. I suppose I should just buy new float needles (the needles with the neoprene tips, hanging from the float tang).

Looks like I'm going to be replacing the fuel rail o-rings, float bowl gaskets, and the throttle shaft seals. Everything else seems to be in good condition.

PS, I used a 6 to 1 lemon mixture boil. Got all of the crud off!, I'm left will a dull finish however.

 

Brosef,

Did you catch Chacal comment about float bowls being installed wrong by Previous owner.......make sure of the proper orientation on re-install....

 

Noted on the float bowls!

I went back to my first post and numbered all of the pictures.


27.)Exactly. There was no screen on any of these needle seats?


28.)

29.)

30.)

31.)

32.)

33.)

34.)

35.)

36.)

37.)

38.)

39.)

40.)

41.)

42.) Brushed bodies

43,)

44.) Clean

45.) Also brushed

 

Did you drill out the plugs over the air screws, or were they already open?
Glad you are having an easy time of it, mine weren't too bad but nowhere near as nice to start with as yours.

 

Your float seats shoud have screens on them......Chacal can supply.....if you are going to buy new floatseats/needles....... Chacal sells the metal tip needles.....I am glad I went with the metal tipped needles vs the neoprene tipped needles....less chance of getting hung up and they won't wear out as the neoprenes will.

 

Nice job of identifying carb numbers on components. Make sure the etching on the throttle shafts is burrless when you reassemble, those butterflies need to sit nice and flat.

 

Will Do, Stumplifter. Thanks

Ok folks, so last night I was going to order my new throttle shaft seals, bowl gaskets, fuel rail O-rings, and float needles/seats so that I could button these babies up and see how they run after a bench/vacuum synch.

Despite my painstakingly organized workspace, I managed to lose a piece last night

Not sure what to call it, maybe the "Synch arm" on carb 3 (See attached picture). There's a good chance I'll find it, but in the off chance that I don't...does anyone have any leads on where to get one without having to buy a whole new rack? I've been unsuccessful so far. Thanks everyone.

 

IF you are only missing the circled 'washer' piece it is no problem.
I would strongly encourage you to get the Deluxe Carb Rebuild Kit from XJ4Ever - it has replacement washers and tons of other good stuff.

If you are missing the entire shaft I bet Chacal/ Len (XJ4Ever) has one of those also.