1979 Carb Rebuild (Pt 1)

Thanks a gain for all the comments and questions regarding the carbs. Hopefully I approached some issues in a unique enough manner to put a new twist on some concerns and procedures.
Yes, i agree with you about the sync-nut heads. They can be a pain. Not so much because of their design. A "mini" 1/8" nut-driver fits them perfectly ......if the head isn't buggered. But that's the issue. Few if any people have a mini 1/8" nut driver so they use what-ever is closest at hand. Pliers, needle-nose vice grips etc. and the ends quickly get so chewed-up they end up asymmetric and so deformed that eventually nothing will hold them securely enough to loosen or tighten. Perhaps this is another need for a "socket-head" conversion.

I'm on it already

These carbs look amazing after all your effort, Scotch. The black finish is a nice touch.
I'm looking forward to reading your report on how the refurbished carbs perform.
By the way, thanks for posting those two photos of your bike. The paint scheme suits it very well, and I like the black camshaft cover. Do you mind me asking how many miles the bike has covered, and if any major work has ever been necessary on the engine. I'm always curious about the durability aspect of the 1300.
Thanks again for this splendid carb article.

After some substantial time taken to accomplish the work which has been documented on this forum I am VERY HAPPY to announce the'79 carbs were installed on my '80 today and after a few minutes of tweaking, they are running the engine as hoped ( expected) but not without some frustration and anxiety !

Needless to say they are equipped with "the Brass floats". I adjusted the 'throttle sync" statically (by "eye-ball"" along with an arbitrary 3.5 turns on all the idle-air screws. Installed them on the bike and turned on the auxiliary fuel supply and the center carb. started puking fuel like there was no tomorrow !! WTF ! Took them off, removed the #2 bowl and checked the float for free travel. ( Hey - anythings possible , right?)The float appeared OK and with the aux. fuel supply connected to the carbs still on the bench the needle-valve appeared to be OK too ! WTF ! Put things back together and returned them to the bike and voila !.....Another good douching of fuel !!! WTF ! Back to the bench and this time removed the needle-valve. Found a piece of aluminum (see photo) stuck in the valve-body. I can tell you it didn't come from the fuel source as I have 2 filters to deal with this nonsense so I can only conclude that it was from my fuel-line mod. which required the drilling and tapping of the end on the right-hand carb to accept the 1/4" MPT. Trust me when I tell you I cleaned-out this area with enough compressed-air to supply a small planet ! So it goes to prove the point that no matter how meticulous you are - shit can still happen !
And to put another smile on all your faces I'll share this as well: While re-assembling the "demon" needle-valve I dropped the tiny retainer spring ! An hour later I found it - by accident. Dropped it again ! #*"F@!~ ! Not so lucky this time. Fortunately I had a spare valve so I robbed the retainer from it. GUESS WHAT ?
F&%#K)(*&^% ! Another half-hour on my knees with a flash-light but no luck. One last chance: I robbed the only one I had left which was from the bench-carb. I use for making the floats. Needless to say I changed my install technique and got this one on successfully! I'm pretty confident that some time next Spring when I am cleaning out the shop, I'll find both of them, after I've stepped on them and rendered them useless!

Note to self: Make a jig to manufacture needle-valve retainer springs.

Once the nonsense was dealt with the carbs sync'd easily and the carbs are good to go....so to speak.

My '80 has 79,143 original kilometers and the engine has never been touched. In Sept. of '80 I went across Canada and back ( coast-to-coast) and returned with a bald Continental rear-tire, a battery that was bone-dry and 1 phase (6 coils) of the alternator-stator burnt to a crisp. I'm on my 4th stator ( an aftermarket high output), replaced the voltage regulator and battery and soldered the alternator connections in lieu of the high resistance terminal-block connector. No problems after that ( about 25 years !)
Water-pump seals leaking have plagued me to the far-side and back. Finally got that dealt with. There's a whole other article that can be written about this - but not now !
I don't like the air-box filter arrangement now that the GM coils are in the tool-tray but will NOT attempt the Pod conversion due to the over-whelming amount of articles which definitively discuss the tuning pit-falls. I'd really like to make a completely different intake/air-filter system that utilizes the volume and resonance principles that all air-boxes are based on but have to overcome some logistics. Another article perhaps? Until then...or until the next Demon arises...Cheers!

Hi Guys,

I'm in the middle of trying to clean my carbs. I haven't got to the point of making a pump to flush though from the three small ports at the front of the bore yet but I'm concerned about my cleaning process so far.

I boiled the three carbs and bowls in distilled water and lemon juice for an afternoon.

I then left the carbs submerged in cellulose thinners for 24 hours. Then rinsed of the carbs under a garden hose and then left them submerged in water for an afternoon.

My carbs now all appear to have a powdered residue over them and I'm not sure how to get rid of it. At the moments I'm thinking I may need to pressure wash them.




So what do you guys reckon? Do I need to repeat the process, pressure wash, or rinse with some kind of detergent?

Cheers
David

CRAPPERS Zed_Thirteen !!! What a mess!! If I got it right your " cellulose thinners" is Methyl Isobutyl Ketone and a search on the internet suggest that you've probably caused a hydroxide catalytic reaction with the aluminum. It's probably not reversible. I don't know if the carbs are salvageable at this point. You may be able to physically remove the oxide but all the internal passages doubtful. And if you did manage to clean up the worst of it, some of the particles that you couldn't get to may break off and foul up the jets. I also doubt that the throttle barrels will slide inside of the carb bodies and might hang up.
I wish I could give you a magic answer, but you need a Chemist here. Sorry for your luck and hope someone can help here. The only thing I've seen worse than this is when someone I know tried to clean their carbs in a caustic soda bath. When they lifted the basket there was nothing left in the basket.