hurry i am thinking about su-ing myself...

[jrock4224]

so heres what i got a set of su's that worked when disassembled but i am thinking i just wanna freshen these up....so whats the source for su rebuilds.....diagrams and rebuild kits ....these are for my goon i wanna get them all assembled and ready to go on that car .....these are flat tops with the two bbolt attachment

 

 

[Guest 510kamikazifreak]

http://www.ztherapy.com/

 

Pam and Steve are great source

[jrock4224]

not much about flat tops ........thee website is kinda a different one to use ...lol

[Guest 510kamikazifreak]

not much about flat tops ........thee website is kinda a different one to use ...lol

 

 

Call them,they are great to deal with.

[jrock4224]

ok  i will ....is there any other good rebuid info

[Guest 510kamikazifreak]

ok  i will ....is there any other good rebuid info

 

 

Only place I would refer someone to

[wayno]

ok  i will ....is there any other good rebuid info

 

 

Z therapy does a great job at rebuilding SU's, I took mine home and had them dialed in(set) in 10 minutes.

I would even venture to say they don't actually rebuild them, they take what you have and make something better than nissan actually ever made.

You get what you pay for when looking at other places, if your looking for cheap, that is what you will get, CHEAP.

If you want something that will last for years with likely no issues, just give them the money they ask for, and that is what you will get.

They are not cheap.

[ggzilla]

Those are 38mm Hitachis. They are so simple that Nissan don't sell "rebuild kits", instead Nissan sells "gasket kits" A and B and the fuel inlet valves separately (uses the same inlet valves as hitachi downdraft carbs). You can make the gaskets you need out of gasket stock. You can re-use the gaskets unless they tear.

 

If you're a real Ratsuner you'll want to clean and re-assemble them yourself instead of paying someone else. The value in Z-Therapy is getting worn out carbs working perfectly, which of course a rebuild kit will not do.

 

Do not sand or scuff the piston or the inside of the cylinders. They need a precision fit for proper operation. This page has cleaning and adjustment information: http://datsun1200.com/modules/mediawiki/index.php?title=Hitachi_Twin_Carb_Adjustment

 

 

Yours look like the IMS (idle-mixture system) has been blocked off. That's a common mod, but it doesn't allow for fine tuning of the mixture, so they end up working like the dome-tops. It's OK.

[converted_to_datsun]

Here's a link with more info about your carbs. They'd L18 SSS flat tops which are functionally identical to the round tops. I have a set of those carbs too I plan to freshen up for my 620

 

http://www.jetlink.net/~okayfine/su/tunacan.html#anchor84836

[jrock4224]

honestly i wanna do it my self i rebuilt several other carbs for bikes and various webers......really just looking for places to get kits and some exploded views ....i would only send them off had i done all of this and there worse then i started with...which is possible with me....i was reading about the drop test and various other tech articles just looking for all i can before i spread them out and put them back together.... i wanna get them on the intake with all the linkage and freshened up before i install them,,,,these are the same carbs that we just put on hans red 521 but his needed only fine tuning

[ggzilla]

Kits? All it needs is gaskets (if torn), and needle valve (if dripping now). They are sold by Nissan and are cheap (Nissan don't sell rebuild kits because they are much simpler than a regular carburetor).

 

Exploded view is what's hard to find. It's only in the Japan and UK factory service manuals after 1973. The Roadster twin carbs have exploded views but they are slightly different from the flat-tops.

[converted_to_datsun]

In the link I sent you it talks about adjustments and needle valves that can be used from 240 su's which you can buy

[ggzilla]

This exploded view is for dome-top, the flat-top version is slightly different, mostly where the IMS parts are and linkage won't exactly match.

 

 
Keyster sells a repair Kit. This one does two Hitachi 38mm carbs

Most of these parts are not needed
* oil cap & plunger rarely goes bad
* fuel inlet needle valves usually are fine

* The crush washers I've always reused, they aren't under high pressure
* it includes new needles, heavens why -- they don't wear out. If you bend one you can buy new ones from Nissan for a few dollars.

[wayno]

I have no idea why no one has mentioned the the shafts wear out and leak, then the shaft bushings need drilled out and new ones installed with new shafts, this is the biggest problem with used SU's in my opinion.

[ggzilla]

That can easily be checked, and if they are still tight, just clean and put back together. If shafts are loose, Z-Therapy can do the work needed.

[wayno]

Here is what I bought more than 10 years ago from nissan, then a couple weeks later nissan had a SU clearance sale, 2 new factory made SU carbs for $400.00, so I went that route and never used these parts.

I bought these for my flat top SU's, as the shafts are loose, and I still have all of it waiting the rebuild.

[I'm BLUE]

You're correct wayno.

I preach it all the time.

Holleys throttle shaft/bushings are worse in less mileage.

Checking throttle shafts/bushings should be a common basic understanding. I sold 3 sets of sus and told them about it. Common reaction was a deer in the headlights look.

 

Nice set of su shafts as well Wayno.

[Laecaon]

I got lucky with my SUs. Throttle shafts had no movement. Maybe it was piece of mind to know Troy Ermish had them on a running car.

 

 

I believe Ztherapy makes the throttle shafts better than new, by a new coating, and using a bearing, instead of a bushing...

[ggzilla]

If it's the shafts that wear, why are new bushings/bearings needed? Isn't it the body casting that wears out where the shaft bore is?

[Laecaon]

By replacing bushings with bearings, they eliminate the sliding of 2 surfaces, which creates wear. Bearings have balls or rollers, which dont slide, but roll. Lots less wear, no having to replace shafts again.

[I'm BLUE]

You're correct ggzilla.

 

In my mind te term throttleshafts means all of that.

I say this because its hard for me to tell what is bad until apart.

 

Holleys are great examples of this as they are wild cards ..lol.

 

Laecaon - I like roller bearing shafts better as well .. tripple dcoes :D :lol:

[wayno]

Both the shafts and bushings wear out.

 

 

[Sealik]

I shipped my SUs to Zeddsaver.

They replaced the bushings, 1 throttle shaft and plate, cad plated the linkage and basically just checked them out.

Not the more expensive roller bearings like Z Therapy...but.... probably good for another 20-30 years.

 

280 bucks...included taxes and shipping

 

The Haynes Techbook Weber Carburetor Manual has info on SU Type H, HD, HS and HIF

[wayno]

I shipped my SUs to Zeddsaver.

They replaced the bushings, 1 throttle shaft and plate, cad plated the linkage and basically just checked them out.

Not the more expensive roller bearings like Z Therapy...but.... probably good for another 20-30 years.

 

280 bucks...included taxes and shipping

 

The Haynes Techbook Weber Carburetor Manual has info on SU Type H, HD, HS and HIF

 

You are in Canada, correct?

[Sealik]

You are in Canada, correct?

 

 

Correct.................in B.C.