really don't wanna - newbe & carb rebuild

Thought I dodged a bullet when I got this XJ running without carb job. Alas the #1 float bowl started leaking when at idle this year. Gotta work on it just don't wanna.

How to best approach parts replacement? Should I remove carbs to determine parts needed or just get a complete rebuild kit?

She ('83 750 maxim) currently gets 40 to 42 mpg when cruzing at 55 mph
and no gas leak under riding situation (only leaks at idle).

I have a couple of exhaust valves that need minor adjustment and petcock has been rebuilt already. I plan on one more ride to drain fuel tank ..... more fun to drain it this way.

Any words of encouragement and hints to keep me out of trouble will be appreciated.

 

Having just cleaned mine out pretty good, I'd say that taking them apart (with decent instructions) and putting them back together (with pictures taken before dis-assembly) isn't NEARLY as bad as I expected. I was to cheap to get all new parts, but I'm not afraid of the work involved if I have to pull them apart again to replace everything inside. A couple evenings quiet work, rather enjoyable actually.

So, there's my hints; take pictures so you know how they go back together, and find some instructions that tell you what all parts to pull off / clean in what order. Then just take your time, stay organized, and don't stress about it. Its kinda like taking apart a clock; looks like a ton of complexity, but when you see how it all fits together, its not so bad.

 

Having the Carbs clean, adjusted and finely tuned will make riding the Bike a great deal of fun.

You can do a thorough cleaning without breaking the rack.

For the first-timer, ... doing ONE Carb at a time will make the job far less intimidating.

The rack is three decades old.
Get quality Kits.
Replace the Float Valve Seats and Pins.
Drive-out the Main Nozzles and clean them inside and out.
Scrub and Polish the Diaphragm Bores.

When the Bowls are off ... take exceptional care to not break a Float Pillar.

 

A new friend from the recent Central New York carb clinic informed me that it's the high E guitar string for cleaning the tiny passages. So, if you play it's time for new strings and if you don't, buy a cheap set at your local music store.

 

Get the valves in spec, properly SERVICE the carbs, wet-set the floats and sync it (bench and vacuum) then RIDE.

Or screw with it forever because shortcuts don't work.

 

One can't replace fuel O-Rings & throttle shaft seals without breaking the rack....I took everyone's advice & replaced these items...

I figured if I was going to clean these carbs...might as well go the whole way.

FULL TEARDOWN........

Chacal's starter enrichment drill bit worked great on cleaning out that particular passage....not sure of the price of high E guitar string ????

 

Yup, some people use the E string, I just go through my wire cut-offs til I find the size I need. I usually end up using either a .012 D-string, or the core of a .020w low D-string from the dulcimer strings that I use. Occasionally I'll need to dig out a different one. Cost of a string?--well, I buy the strings in bulk, so it comes out to less than $1 per string........so the string is on the instrument, the cut-off is in the box. Cost of the cut-off (read "tool").......0.

Maybe a handful of string ends will be the door prizes next year. LOL

fiveofakind--good for you! You're going about it the right way


Dave F

 

I've always been afraid that wire would damage the passages. What passages are you referring to?

 

tabaka....the starter enrichment passage in the float bowl.....this is in use when you apply choke on a cold start......

Hogfiddles...check your PM....I would like to know how your shim pool works...

Thanks

 

You'all scare me. Pictures I can take, but guitar wire ...... my cousin Vinny used that in his profession. :? Thanks for the comments, I'll start making notes and ordering parts from Chacal. Any preference for OEM or aftermarket? OEM looks expensive.

 

Hogfiddles is suggesting an high E string or you can use the drill bit that Chacal sells for this particular passage......believe us......this is the smallest passage in the entire carb.......you need to get all 4 clean for a smooth cold start.....until she warms up.....


Per Chacal's catalog:


Aftermarket wire gauge BOWL STARTER JET DRILL BIT. As you will quickly discover if you ever try to clean or rebuild your Hitachi carbs, the tiny, non-removable starter jet that is stuck wa-a-a-y down at the bottom of a drilled passage in the carb bowl is next to impossible to clean. For one, did we mention that the jet opening is TINY? And did I also mention that it's stuck way down at the bottom of a small passageway, and basically unreachable? AND THEREFORE, NO ONE EVER REALLY EVEN ATTEMPTS TO CLEAN IT OUT? And that a clogged starter jet not only means trouble starting and idling, but that starter circuit is actually also involved in idle and off-idle performance? Well, how do you actually clean it? Even the tiniest cleaning rod in our carb passage cleaning wire sets (above) aren't small enough to fit through this starter jet (it is THE smallest jet-passage in the entire carb)...

Well, here's how you clean it: with this tiny drill bit. Just big enough to get through the jet, but not big enough to ENLARGE the jet (that's a huge no-no), this high-speed steel bit can be gently rotated (but never "pushed", as it will break) through the toughest of crud. This is the only way to properly clean these starter jets.

NOTE: this is a TINY drill bit, and will not chuck into a standard drill chuck. You have to use a mini pin-vise attachment or do it carefully by hand...... ALSO: this drill bit is a mere 1-1/2" long, and as such, will disappear below the top "plane" of the bowl as it goes down into the jet. You will have to use a pair of very slim needle-nose pliers to grip the tip of this drill bit and rotate it!

HCP2296 Aftermarket BOWL STARTER JET DRILL BIT, for Hitachi carb bowls used on all XJ650 (except Turbo) models, all XJ700 non-X models, and all XJ750 models.
$ 11.95

 

I have visions of me screwing this up too. Oh what could possibly go wrong.

 

unless you seriously damage a carb body, break a float pillar, rip a diaphragm.... you will do fine.

 

Have faith.....cleaning the passages is easy.....you can do it....there is a lot of help here.....

 

Buy a Composition Notebook.

Number, ... as you Write-down each move.

Photograph the arrangement of the Enrichment Assy.
Center-punch the Right-end of the Rod.
Mark the way the Activation Arm fits.

When you are working topside, ... reattach a Bowl (finger tight) to protect the Float Pillars.

 

Not sure what a float pillar is, but guess I'm about to learn.

 

Float Pillar, ...

"Float Hinge Pillar"

There are 2 of them.

You'll see.

 

Float Pillars - each carb has 2 - the float floats between held on by the float pin.....confusing....not really....

 

see pic....float, float pillars, float pin, main fuel jet, pilot fuel jet

 

So still confused .... I need these? What else will I need? What's difference between Aftermarket & OEM besides money?

HCP18863 Aftermarket Hitachi HSCxx-series carb DELUXE COMPLETE REBUILD KITS, for use on all XJ650 (except Turbo), 1985-86 XJ700 air-cooled models, and all 1981-84 XJ750 air-cooled models. Contains all the parts needed to do an entire rack of carbs:
$ 274.95

and,

HCP10SET4 OEM Hitachi FUEL INLET - FLOAT VALVE ASSEMBLIES, set of 4:
$ 339.95

or

HCP18795SET4 Aftermarket Hitachi FUEL INLET - FLOAT VALVE ASSEMBLIES, set of 4:
$ 69.95

 

You don't need float pillars...they are permanently attached (unless you drop the carb with the bowl off....then they are permanently DE-tached). Many aftermarket kits have issues...such as needles that won't seal when shut, or jets that don't flow well. Anything you buy from Chacal (XJ4Ever) is top-drawer whether original or aftermarket. You can't go wrong.

 

Thanks for all the comments ..... I'm starting to get a feel for this.

 

well, if it were me, I would buy the aftermarket as opposed to OEM....340 vs. 70...you make the choice.....

I am not even seeing 2 of the 3 part numbers you listed.....

 

Numbers were cut & paste from chacal e-mail, so must be there somewhere. Any specific reason for Aftermarket? Chacal indicates that aftermarket has rubber tipped needle and best for E-85 fuel of which I have never seen here.

I've no real preference. Just want it to run smoothly and efficiently.

 

Spring-loaded Viton-tipped needles are a nice upgrade.

 

Are these in the Aftermarket kit? I assume that the Viton-tipped needles are the "rubber" tipped as described in the Chacal package? What is the performance or wear benefit of using this upgraded needle?

 

Less likely to leak-by.

 

Thanks .... sorry to be pesky question asker ........ but really new to carb internals.