CARB ID HELP NEEDED.........

Okay, I've got a set of carbs here that the seller claimed were off a '83 XJ750 Maxim.....but I don't think so.

That bike should have used Hitachi HSC32 carbs, which I am very familiar with.

These carbs are marked on the bottom of the float bowls HSC33-11, 41Y-00, 31122.

The bowls are "single drain screw" bowls, meaning they are specifically either for the RH or LH side carbs.

The main jets in the carbs (all 4) are stamped "40"......yeah, I know!.......and the pilots are 43's.

The air jets are 70 and 225's. The needles are Y13's.

These carb bodies have what appear to be separate vacuum and fuel inlet ports.

Other than that they look like Hitachi's, but of course I can find no stampings to indicate such.

The starter plungers operate on the top of the carbs, not the sides. They are not Mikuni carbs.

The bag they came shipped in said '85 700........

Any idea how I can ID these carbs properly? I have someone who needs two of the carbs (he broke his) and I want to sell him the right thing.

Can anyone help? Thanks.

 

I've got a friend at work who's father worked for Mikuni, I'll throw the numbers at him and see what floats up. Meanwhile, anyone else able to help?

 

According to the book the xj700 uses Hitachi HSC33's but I have never checked to see what model my carbs are and.

Faighaigh.

 

Seems they´re HSC 33-11 Hitachi from a (european) XJ750F (Modelno. 41Y as opposed to the 11M (european)? Seca).

http://www.xj-ig.de/xj750f.htm shows some of the jets/needle specs:

Hauptdüse (main jet): #106
Düsennadel / Clip Stellung: Y-18
Nadeldüse? (needle jet)?
Leerlaufdüse ("idle jet" - not yet familiar with the different jet names)?: #40

On my XJ700N I have Hitachi HSC 33-12 (1FG 00 50109 on the float bowl), and my jet sizes are stock, I believe:
main: #107
Pilot (the one in the bottom beside the main): #36,5
needle (don´t know - can check if you want, have the carbs apart now)
air jets: #70/#210

 

Thanks guys for the insights.

Does anyone have any pictures of HSC33's? Or 700 non-X carbs?

Also, any ideas why the main jets would be stamped "40"? I mean, they're definetly main fuel jets, the hole is big enough to run a paper clip through, and it's a nice crisp sharp "factory" stamping on the jet rim, not something home-made.

Hitachi doesn't have some hidden place where they cast the carb series or model number on the body, do they?

I guess it could be a set of Frankencarbs, cobbled together from many bits and pieces, but it sure is a nice looking, very CLEAN set, with all the needles, jets, etc. matching in size/number/style.

Thanks again.....

 

http://www.slygrin.net/xj750/html/body_carbs.html

Haven´s seen anything else than the writing on the float bowls and the Hitachi logo on the outer sides, just above the floatbowl.

Also http://www.xjbikes.com/Forums/viewtopic/t=3649.html - alives great pics of 650 hitachis (Hsc 32)?

As said I´m having the carbs apart at the moment - let me know if you want anything specific photoed (hoping to have them assembled by tonight or tomorrow).

 

Couple more of the HSC33-11 (750F 41Y) here:

http://www.treasureboards.com/xjphotos/c1.jpeg

http://www.treasureboards.com/xjphotos/c2.jpeg

And check out the entire list of photos (lots of the interior):

http://www.treasureboards.com/xjphotos/

 

YES!

We have lift-off!

Those 750F/41Y carbs are the ones......

Okay, part of the problem solved.

P.S. why all those vacuum lines?

Thanks Finn!!!

 

You´re welcome.

Don´t know about the hoses 8they´re on my carbs as well) but the poster of the pics asked and Dwayne answered in the XJ-maillist:

"ladzior ladzior,-

I don't have a set of 33mm Hitachi carbs to look at, but they were used on
the 41X model sold here. I believe they are functionally the same as the
32mm used on earlier 750 models, except that the float bowls are vented
through those hoses instead of a passage.

To work properly, the starter enrichment circuit must draw both air and
fuel. The straw descends into the passage above the jet, but that passage is
also vented. The "choke" initially draws pure fuel but only for a moment,
since it can draw fuel faster than the jet can admit it into the passage. As
soon as the fuel level drops down below the level of the straw, it starts
sucking air as well.

tafn

dv"

and (from the asker):

"Ok, thanks! So these hoses are float bowl vents and
also provides choke system with air ?? "

 

Finn, you are truly on top of your game.

Now, doesn't Dwayne live in Canada? So when he says in the above quoted post "..but they but they were used on the 41X model sold here."---does this mean that these HSC33's were used on Canadian models..and what is a 41X model? Is that a 750F?

Thanks again!

 

Thanks man; I´m right in the middle of it 8) (Half way through reassembling the carbs).

Yes, I think he does; there´s no 41X in the model-code identification chart on the XJCD - but there is a canadian -84 XJ750RL with the modelno. 44X..

 

I can look at those Tops ... "The Hats" ... that are sitting-there, on-the-bench ... and see the tell-tale sign for Hitachi.

See the "Slant" on the Carb Top Cover.
They're Hitachi's!
That and the configuration of the Enrichment Valves, pivot pillars and Pilot Screw location.

Hey ... Quick ... get a Patent for the creatively cut-out plastic milk gallon.
I love the -- "Pour spout" you left for dealing with the fluid transfer!

Brilliant!
Brilliant!

 

The hoses are the Over-flows.

The Bowl should have two that face Outboard Left with drain screw access ... and two that face Outboard Right with drain screw access.

Not uncommon to find these misplaced ... usually indicates somebody removed them and mixed things up.

 

Thanks Rick - it´s a free-for-all design to use 8)

- and, by the way, as always, your carb-guide was an invaluable help; consulted it for every new part I was facing. Will get back with my experiences in The FAQ section when all´s put back together again..