Goin in, 79 carbs

[whatscooking]

When you go into a carb rebuild knowing the fuel joints will need taken apart how do you deviate from the book as far as tearing down and cleaning and checking the passages. Also in the book all the cleaning is done with a spray can and jet cleaners, nothing said about dipping the whole carb body. This is my first time into a CBX carb.

[CopperCollar]

No real trick, follow Mike Nixon's book paying special attention to cleaning out those small passages. Study what hole should have fluid coming out of it when the cleaner is sprayed into an orifice.

So far as dipping in carb cleaner, I have and have gotten away with it but since using an ultrasonic cleaner I will never use carb dip again.

I am sure Dave or one of the other carb specialist will be happy to guide you in this endeavor. It is rewarding once you get through it and often challenging.

Mike

[whatscooking]

The dip I have been using for some time on other types of carbs is Pine sol. It has worked very good for me. I have the carbs off and ready to disassemble. The vent Tees are falling apart and there is a leek between 3-4 carb fuel tube. Also how many of you defeat the air cut off valve. It came in the kit I got but in the book it is advised to block it off.

[steve murdoch icoa #5322]

I have always used it.
Just a check for any tiny holes in the diaphragm and that the rubber washer/plug is properly installed.
The smart carb guys will be along.

[daves79x]

You will have no problem dipping the carb bodies as long as you use plenty of hot water and compressed air to dry them. Don't take out the throttle plates, just let the carbs dry overnight and free up any sticky ones the next day. No matter what you do, the idle circuits still have to be verified completely clean, usually necessitating removal of the pilot jets.

Dave

[whatscooking]

I guess I should ask my question a little different. With Mr Nixions book he goes through the cleaning while the carbs are together but I know the carbs I have will need to be separated to repair fuel tubes. Should I clean the carbs with spray cleaners then put the bowls and such back on then separate carbs and do the O rings for the fuel tubes. Normally I would tear everything down dip and then clean jets out and then put everything back together. Also I got a surprise when I took one of the fuel bowls off, one of the post for the float is broken off where the pin sits. I have seen the repair kit, what does everyone think about that repair?

[steve murdoch icoa #5322]

Just talked to a guy 2 weeks ago at a vintage swap meet that had done the post repair.
He used the kit from Randakks and was very happy with the results. http://randakks.com/collections/honda-c ... repair-kit
I have never needed to use one but would not hesitate in using this one.

[whatscooking]

I hate doing anything like this the first time for fear of destroying something. I have been getting hung up on the proper way to clean one of these monsters. I started checking passages with the Berrymans only to find plugged and weak spray coming out so I went ahead and dissembled the carb like the book said and now have it soaking in Pine Sol.

[herdygerdy]

Hi Whatscooking,

Firstly, good on you for taking the leap into the mysteries of CBX carb rebuilding. While it is not for the faint hearted, the rewards are immense when you do finally get them right, and get them right you will.

Everyone here started just like you are at the moment, so those feelings of trepidation & OMG! are normal. But we are here to help you along this journey of discovery.

Take your time, be patient and be prepared to walk away for a while when, not if, it becomes overwhelming and things don't go right.

Just to re-assemble a fully stripped, cleaned and prepped set of carbs from scratch can take even the experienced the best part of a full day, so think of this as some excellent 'motorcyclin' meditation'.

A couple of useful tips. Firstly, when re-assembling pairs of carbs, a match stick will be your friend. Just cut off two pieces with nice square parallel opposing surfaces about 6-8 mm long
and putting them back together will be a joy, not the normal cussin'and yellin' experience many of us found when starting out.

Like so.....



Hmmm, I think you might be getting the idea....



and sticks in place and ready to join...




and now for the final firm but GENTLE push together




Be sure to recover both pieces of matchstick as they are pushed out backwards by the fork from the neighbouring carb.


And now to unblock those pesky accelerator pump jets, which is best checked and fixed BEFORE joining the carbs together....

While the carbs are split into single units, be sure to check the accelerator pump nozzles as per Mike's book. If good they should squirt cleaner well out the front of the carb throat.

Take two of the rubber idle jet plugs (try first with your old ones and if too small, the new ones in Randall's kit are the perfect size and won't be damaged by this procedure).

Insert one into one side of the accelerator pump circuit in the body of the carb like so....



Now flip the carb over and carefully fill the carb body accel. pump hole with cleaner, right to the top of the carb body. May even need to tap the carb body gently on the bench to get all the air out.

Then push the second idle jet rubber plug into the circuit right on top of the cleaner.

Then get yourself a big pair of multi-grips and squeeze the two rubber plugs together to apply serious hydraulic pressure to the blocked jet, like so...



All going well you will feel the pressure build, then suddenly "Oh! what joyful release of fluid" and hey presto, a clear accel. pump jet.

Re-check by squirting more cleaner through the circuit as per Mike's excellent book and a final blow through with compressed air and you are good to go.

But...be sure to check again just before you put the carbs back together - remember, as they say in the classics, "assumption is the mother of all stuff ups"

Keep us posted on progress and don't hesitate to ask if not sure. Remember, we are here to help.

Enjoy the journey.

Cheers...Tony

(Oops! thought this felt familiar, apologies for kinda double post as I now realise I described these tips on another thread in this section, mods feel free to remove if you wish). The older I get, the more new friends I get - every day!

[whatscooking]

The feeling I got when all of the tubes unscrewed after I ground a screwdriver down to fit in the hole was pretty good. I know what you mean about walking away, sometimes I get stuck\ brain fart\ rush, I have learned to walk away, a bike ride is the best then.

[whatscooking]

Spent most of the day putting the carbs back together. Everything went fairly well until #6 carb, the last one I put together, I went to drop in the needle jet in and got a no go when installing the emulsion tube. Never forced anything even tried putting it in the freezer and heating the housing, it would just not go. Still really don't know what I did but finally I got a bite with the threads and I got it slid in ever so gently. Anyway I got all six together and ready to tackle the O rings and tubes tomorrow.

[daves79x]

You're not going to want to hear this, but you really should have assembled the bodies together before you put each individual carb back together. You are going to have some headaches trying to connect them. Sorry, I've been traveling and didn't keep up with your questions.

Dave

[whatscooking]

What should I take back apart to help with this?

[daves79x]

Stripping each carb of it components is easy and the least of your worries. On that subject, did you remove the pressed-in #35 pilot jets and clean them? Did you then verify that fluid would pass through them and out the cluster of 3 holes in the carb throat? Did you further verify that all air bleeds were open and the pilot screw passage was open (you did remove each pilot screw, spring, washer and o-ring?). Did you also verify all accelerator pump nozzles were clear and that the pump mechanism was properly adjusted to actually work? Do all throttle plates snap shut and seal the throat completely without hanging up?

If you have done and verified all the above, then begin re-assembling the bodies to each other, one bank at a time, then assemble the two banks together. You will have issues assembling the joints that join the two halves together. Heat the rubber joint covers to ease re-assembly, if they didn't tear off when you took them apart. Reproduction replacements are available.

Once you get the bare bodies all connected and the frames bolted on to hold everything in place, then install the choke shafts and plates, making sure they open and close freely. This is sometimes quite difficult.

Then assemble all the components in each carb body under the bowl. Carefully adjust each float to the proper height. Then verify one last time all accelerator pump nozzles squirt, then install all the bowls, checking each first for cracked standpipes. Then the carbs will sit upright on the bowls and you can re-assemble the tops of each, carefully cleaning the towers and receptacles with Q-tips and insuring each pair you assemble slides freely. Make sure to install the plastic bumper rings correctly.

Install the air-cutoff diaphragm looking for any tears in it. Make sure you install the o-ring properly.

It is very important to now bench sync the throttle plates very carefully. Then wet-test the carbs for 24 hours for any leaks. Common will be a few float valves that weep. They may seal, but further cleaning or replacement may be needed.

If you are EXTREMELY lucky, the carbs will work OK, if not, and it's very typical, they will have to come off again to do more cleaning or repair.

There are many other little procedures and tricks to ensure the carbs work correctly the first time, but the above is a good start.

Dave

[whatscooking]

Pretty much yes to everything you have brought up except the pulling of the pilot jets. The book that I bought with the o\h kit said leave them alone, I know it was a gamble. Shouldn't the choke shafts be in before the half's are bolted together and how do you properly install the rubber plugs? And another question, what do you soak the old O rings in on all the tubes to help with removal? Time was limited for shop time today but I did try to fit together #1 and #2 with the old o rings on the tubes, with the tips I have read about here it went together slick.