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Separation of Carb bodies?

Started by Tor-King, September 30, 2012, 10:22:39 AM

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Tor-King


I am in the process of cleaning my carbs and would like to know whether it is critical to separate all the carbs before placing them into an ultra sonic cleaner.  The jets, floats, needles, diaphrams and all other internals will be removed, of course.  The reason I ask this question, is will they be effectively cleaned if they are kept on the alignment brackets and will it hurt any o-rings remaining in the T-Fittings between the carbs? (I am hoping to keep them together as an assembly as I will be bringing them down to the local dealer to get them cleaned but I want to assemble them.)

Thanks a bunch,
Dean
1993 Yamaha FJ1200
1988 Yamaha FJ1200
1986 Yamaha FJ1200
1984 Honda Nighthawk S 750
1972 Yamaha XS-2
1972 Honda CT70
1974 Honda CT70
1992 Yamaha DT50 MX
2012 Honda CBR250R
2008 Honda CBR125R

Flynt

Quote from: Tor-King on September 30, 2012, 10:22:39 AM
critical to separate all the carbs before placing them into an ultra sonic cleaner. 

No...  you'll make the job much harder with no benefit.  The stuff you're trying to clean is mainly the small ports inside the carb bodies.  Leave the carb bodies bolted together to clean.

Some replace the mounting hardware with SS as well, but even if you do that I'd do it one fastener at a time and leave everything bolted together for cleaning.

Frank
There's plenty of time for sleep in the grave...

Tor-King

Thanks Flynt!

That's what I was hoping to hear.  Will it hurt any o-rings left in the carbs?

Thanks again,
Dean
1993 Yamaha FJ1200
1988 Yamaha FJ1200
1986 Yamaha FJ1200
1984 Honda Nighthawk S 750
1972 Yamaha XS-2
1972 Honda CT70
1974 Honda CT70
1992 Yamaha DT50 MX
2012 Honda CBR250R
2008 Honda CBR125R

racerrad8

Quote from: Tor-King on September 30, 2012, 10:41:58 AM
...Will it hurt any o-rings left in the carbs?
Dean,

The best way to properly clean them is by fully dissembling the bank. They fuel inlet passages, with the inlet tee(s) and/or transfer tubes installed, have pockets where debris will gather under normal use. The ultrasonic cleaner will break the debris free, but you can get it all out unless you pull the tees. With the tee(s) and/or transfer tubes out you can ensure cleanliness.

You really cannot hurt the o-ring between the carbs because they are already 20 years old and are hard and shrunk up.

For the best cleaning, you should break the carbs completely down, it is not hard. You need to replace all of the o-rings between the carbs anyhow and the only way to do that is to pull them completely apart. This will also allow you to pull the choke plungers to get all of the debris and moisture from the ultrasonic out of there too.

Keep an eye out for the four three springs used at the carb sync/balance screws, those are the only things that are going to "jump out" and get lost.

Randy - RPM
Randy - RPM

John Hopkins

If you don't separate the carbs you don't have to balance them..but you should still clean everthing and replace all the O'rings and check each diaphragm for pinholes and splits.

Replace any damaged diaphragms and use a small dab of silicon gasket gel in the diaphragm groove so they stay in place as you refit the covers..

also don't forget to make sure all the floats are at the same height and clean the float seat strainers..

If you are going to all the trouble of cleaning the carbs it would be silly not to fit new repair kits.

John.
Beauty is only skin deep..But ugly goes right to the bone!

fintip

There's one right way to do carbs, and since you have them off, it's really worthwhile to just go all the way. Putting them back together isn't nearly as scary as it sounds if you just have a good set of instructions. I did a complete cleaning of mine on my XJ650 (just another inline4 SJM/yamaha carb set) not too long ago and filmed the process pretty thoroughly (including ultrasonic), and if I will just sit down and edit all the footage, it'd be a pretty great how-to.

But really, the depth of your cleaning will be substantially improved if you break the rack.
fjowners.wikidot.com

Not everyone understands what a completely rational process this maintenance of a motorcycle is. They think it's some kind of a knack or some kind of affinity for machines in operation. They are right, but the knack is almost purely a process of reason.
-ZAMM

IBA:54952

Tor-King

Hey guys!

Alright, you've convinced me to tear the carbs down and separate them.  But here is a new question: How do I identify each carb body as in the order they are on the bike?  Should I somehow mark them with a 1, 2, 3, 4 before they are placed into the sonic cleaner?  According to Raforth's guide, each removed piece should be placed into the corresponding carb body.  Any suggestions on how to mark them so I put them back in corresponding order?  Now I just need to order a few things from Randy in the next little while.

Thanks,
Dean
1993 Yamaha FJ1200
1988 Yamaha FJ1200
1986 Yamaha FJ1200
1984 Honda Nighthawk S 750
1972 Yamaha XS-2
1972 Honda CT70
1974 Honda CT70
1992 Yamaha DT50 MX
2012 Honda CBR250R
2008 Honda CBR125R

racerrad8

The throttle linkage will only allow assembly one way.

You can surely scribe the position into each carb.

Randy - RPM
Randy - RPM

tmkaos

Hi Tor-King

I just pulled my carbs down too - I took photos first of the carbs together, then pulled them down and kept all the parts in 4 piles -cleaned each pile individually. It is easy to see which carb goes where once you have them pulled down as the associated bracketry leaves different clean marks on the carb bodies, and the inner and outer carbs differ in the fact that there are blanked ports on the outer 2 carbs where on the inner 2 the fuel transfer tube goes between them - I have a '92, possibly if yours is an earlier pre-fuel pump model the set up is different..
Anyhow, take photos, stay smart and keep it in separate piles as David R's guide says and you'l be good to go.

**Also - find the link to Andyb's pictorial accompaniment to DavidR's guide - I found it invaluable!!**

Good luck!

James
'92 FJ1200 - '07 to present
'83 VF750S Sabre - '04 - '07
'87 VT250FG - '94 - '98

Pat Conlon

Quote from: John Hopkins on September 30, 2012, 01:17:03 PM
If you don't separate the carbs you don't have to balance them.......


Assuming they were balanced to begin with...In my humble opinion, You should always balance or sync your carbs any time you remove them for cleaning. Why not? It's a easy task. If you are going thru all the work to clean your carbs go ahead and spend the extra minutes to sync them.
If you don't have access to a carb sync tool, make one or buy one.
If you want to do the work on your FJ yourself, go ahead and invest money in some proper tools to do the job right. You have a set of metric sockets, open end and allen wrenches don't you? A selection of screwdrivers?
You really need access to a set of carb sync gauges. It's fundamental.
Just as proper jetting is important, a job you only need to do correctly one time, Carb sync on a FJ is critical for a smooth running, happy motor and is a task you will need to do multiple times over the course of years.
I'll get off my soapbox now.....carry on.
1) Free Owners Manual download: https://tinyurl.com/fmsz7hk9
2) Don't store your FJ with E10 fuel https://tinyurl.com/3cjrfct5
3) Replace your old stock rubber brake lines.
4) Important items for the '84-87 FJ's:
Safety wire: https://tinyurl.com/99zp8ufh
Fuel line: https://tinyurl.com/bdff9bf3

Flynt

Quote from: Pat Conlon on October 01, 2012, 07:31:33 PM
I'll get off my soapbox now...

Gimme that soapbox...  replace all the hardware with hex head stuff!  :diablo:

Damn, that was already the plan I guess   :lol:

Frank
There's plenty of time for sleep in the grave...

fintip

I both keep everything in separate piles (I buy a set of paper cups and make four rows, one row of cups for each carb), and I also inscribed thinks like bowls, bodies, butterfly plates, etc. Just carve somewhere not visible with something like a paperclip, or some tool you have handy. Aluminum is soft.
fjowners.wikidot.com

Not everyone understands what a completely rational process this maintenance of a motorcycle is. They think it's some kind of a knack or some kind of affinity for machines in operation. They are right, but the knack is almost purely a process of reason.
-ZAMM

IBA:54952