2024-12-29 Kz1300 Carbs - Scotch Tool, Reassembly, Float Check, Bench Sync

2024-12-30 More Scotch BlowJob

I found it hard to remove the Scotch tool. I thought it would be nice to have something to grab onto and they're already was a threaded hole, but I cannot find any thread that would fit a female. I tried M6x1 and M6x1.25.  Also SAE. The M6x1 would engage 2, maybe 3 threads then get tight. Nothing worked so I tapped it with an M6x1.

Went to the hardware store by a nice little knob, what makes it a bit easier to remove the tool even with arthritic fingers.

Someday, I'll have a real shop. But not today. For today, I'm grateful for nice weather.

I think I got one of the last remaining scotch tools available. I don't ever recall seeing The stop plug in picture. So I went to the hardware store and figured it out. It's a M 5 x 50 mm wall with standard plumbing washers to make the seal.

55 mm would have been better, but this is the biggest M5 my hardware store I had.

Here she is all sealed up.

 

Inside view.

I use a little grease to facilitate an easier removal.

Ready to start the flushing process for scotches document.

I use the recommended salt, or thinner, with about 40 cc per flush.

I do have a couple of enhancements for scotches document. When checking for clear passage ways of the four little passageways by the butterfly, the idle air screw must be turned about four terms out to allow the fluid to reach the four holes. I had flushed and flushed and flushed and flushed and flushed and flushed and still didn't have any flow through the three smaller holes. Only the larger hole had flow. Got to look at the passageways and saw that this needle would have to be open.


The top hole is for the idle circuit. Note that in this picture, the carburetor is upside down.
 

Conversely, the bottom bowl is for the high speed circuit, meaning the emulsifier tube and main jet.

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2024-12-31 Scotch Blow Job OH SHIT

Sometimes, well, sometimes.

Things go don't as planned.

As in 'Oh fucking Shit' wish I hadn't done that.

Started off working on carb #2, using the Scotch Blow Job tool.  But first, I had noticed that at the recommended 3.5 to 4 turns out on idle mixture adjustment screw,
that the needle jet was loosey goosey. So went to anothe hardware store to find a longer spring.

Thought I had it.. but no.

Only a 3mm will fit into the recess the 5 mm OD spring I found.. won't work.
Should have taken this as a sign and stopped. but NOOOO..

Pulled the needle jet to see settings and make measurements.. Little did I know this was soon to be the last I've seen of it.. sigh.

Circlip at 4th position.. with a shim washer to raise it slightly higher than a 'groove' setting.

Shim washer thickness.

Needle jet stamping.

All brass is new after 'WiredGeorge' rebuild. Not sure what 'kit' he uses.
But the taper looks good.

Thought I'd take a measurement of one.. then compare the other 5 to determine if length was the same.. To save time from pulling the slide circlip on
each and slide.. So far so good.

Off we go.. pics out of sequence..

Noticed some metallic debri on the de-cell diphragm. WTFO?

Like the carb body I worked earlier (this is the middle carb) some crap in this location. Must be a 'drop' point with little to no fuel flow during use..

Noticed the emulsifer has a larger diameter passageway than the ones below it..

Then discovered this hole.. Where does it go? What does it do?
 

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It simply goes through from top to bottom chambers..no idea why.

Carb casting flashing..the #1 carb had the same issue. Might clean it up, if nothing else to prevent vibration breakage and potential internal debri..

Now for the Oh Shit part..
Sigh. When attempting to reassemble the needle into the slide..my arthritic fingers gave way to the spring pressure, and the needle, spring, top cap spacer..

Are somewhere here..

I looked for over an hour, could not find. 

Will have to remove contents from drawers on right hand, pull it out, and look behind.

Well, just Fuck Me.

What went airborn...

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Well, fuck 2024. I'll find it next year? 

2025-01-01  Scotch Tool Cleaning Day 3

Hitting the homestretch now.

Another 3 1/2 to 4 hours and all three carbs have been cleaned using the scotch tool, given a blow job with the air compressor at 40 psi.
I still have the problem of the missing needle, spring, and top hat that went for a cruise into space somewhere in in the shop.

I am hoping that the carb kit has these parts, otherwise I will be searching for hours.

My little work area. Old-school stereo upper left-hand corner various old drivers licenses on the wall. Someday he'll become more organized.
As you can see, I have scotches instructions in the bar, right hand corner, and then following it verbatim. Well, actually, it's more like a procedure underneath a revision.

I disassembled one of these to see where the needle position was clipped. Upon reassembly, the spring loaded needle took like a rocket into space. I did, however, take measurements so I could measure the remaining needles without disassembling them. I have to find a better way to reassemble safely.

Here is the next one.

Speaking of diaphragms, I decided to try a little RuGlide to moisturize. I remembered working in a print shop with all set presses where we would treat the blanket with a rubber rejuvenator that extending blanket life, increasing print quality. Much to my surprise the root glides work fantastic on these diaphragms. How long it will last once exposed to gas and vapor I do not know but I will say there was a 80 to 90% improvement in the suppleness, flexibility after the treatment.

Of carbon silica. The last carpet that I worked on had evidence of carbon silica in the fuel coast enrichment diaphragm. Not good. Very disappointed with my so-called professional carburetor rebuilders, and it gets worse from here.

Look at this intake throat. It was so bad that the butterfly would not close fully on the spring alone.
This is unexcused. How much silicone did that cylinder just when I try to run these carbs?

This picture is under four times magnification from the iPhone. To the naked eye, it was barely visible.
But I did notice a hitch in the get along when the butterfly was trying to close underneath the spring pressure, which got me to looking.

Then there is this on the emulsifier tube. All six had shown signs of heavy material removed to fit into the carburetor body. But this one was especially bad. I actually had to drive it out using a small hammer and drift punch. Once again, unexcuseable! Really shitty work.

I have new brass on the order and will install before putting the carbs back on the bike. Use my lathe and a scotch pad to remove the burrs.

The last two needles get measured.

My measurement technique is crude, and when the new brass arrives, I will ensure they are identical in length.

This is the first diaphragm I applied RuGlide to. This was a substantial improvement.

The clock says 5:47 PM, it's dark and I am done for the day.

At this point, I have a much better understanding of how these carburetors work. I understand the idle circuit and passage ways, as well as the high-speed circuit and passage ways. The scotch tool is really a wonderful invention, well thought out and well made. I have already spent the time to learn how to synchronize on the bench so hopefully that process will go more quickly this time around.

Next up, install the new brass when it arrives, check the fuel level in each bowl and adjust as needed. I also would like to find new fuel transfer tubes that connect fuel delivery to each carburetor.

That's it for now, goodbye.

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2025-01-08 Kz1300 Carb Reassembly

After cleaning the carburetors with the trademarked, and brilliantly designed and built scotch tool, it's time to reassemble the carburetors on the bench. I also received a carburetor kit with brand new brass, so I was able to replace the missing in action spring that went flying into outer space last week. After tearing the shop up from top to bottom, I was able to locate the needle, circle clip, washer, and plastic spacer. But the spring is long gone. Happy to see that the spring is part of the kit.

Went to Harbor freight and purchased a set of snapper ring pliers.

For the price point, these are pretty nice, even though they did not work in this application.

Let the games begin. This was the only pair of snapping players I had that would fit into the inner diameter of the slide and still access the circle clip.

Here is the carburetor kit from Damen Ding, China.

To facilitate indexing of the tab into the hole, I marked the tab so I could easily see how to place the plastic into the slide.

This time, instead of taking a chance of the needle and assorted parts taking a lift off into outer space, I used
gorilla tape to ensure nothing would escape while I secured the needle underneath spring tension.

Years ago, a very good friend of mine, Hal Risser, talked me into buying a set of hemostats.
This is a very incredible useful tool.

Another friend of mine, a neighbor, Gary, former high school, shop teacher, said he sometimes used plastic to ensure flying parts were contained.
This is a great idea.

Sure, it's a little awkward to work inside the bag, to have visibility, but it sure is easier than tearing the whole shop apart looking for missing parts.

Glory is mine. Reassembled and no space junk.

I have new fuel transfer tubes on order, but thought you still might be OK to use.
I use Parker O-ring seal to keep the O-rings fresh. It is good stuff.

The rest is pretty straightforward, now to check the fuel level, perform a bench synchronization, and then hopefully have a good install with better results.

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2025-01-23 Kz1300 Carb Fuel Level Prep

Made an adapter so I can't check the fuel level in the carburetor bowl.
It is a bolt of the right size, drilled a hole in it.

Added an O-ring.

Some Tygon tubing.
 

Replaced the newer style float bowl with one from the 79. Testing purposes only.

Replaced the petcock on my TT 500 auxiliary gas tank. It will sit on top of a ladder and gravity feed the carburetor rack.
For now, I am out of time and daylight. So tomorrow is another day.

2025-01-24 Kz1300 Fuel Height in Float Bowl Check

Here is the test set up. A 1976 Yamaha TT 500 gas tank with a new petcock up on a ladder.

Acceptable range per the factory service manual.

I do not know what they're talking about when they say the zero line.

Had to add safety wire to keep it from leaking.

Everything nice and clean. However, I did notice small, very small, particulate matter from the black ceiling gasket.

I always use anti-seize on all my fasteners.

One very well used factory service manual.

2025-01-31 Install Rebuilt Carbs

Before installing, check that all screws were tight, but the bench synchronization was correct.
Installed the vacuum extensions before plugging the carbs into the boots. Easier that way.

Manometers hung. I even checked that the restrictions in the tubing were the same for all six.

Pulled the spark plugs they all look good.

Installed. And clamped down.

I sure hope this works.

I would like to ride the bike while the weather is still cold..

2025-02-03 No Fuel Air Adjustments

Today was the big day. Going to fire the old girl and see if all my carburetor work works.

As you can tell by the title, the answer is no. I still have work to do.

An initial fire up was running very poorly. Pulled the spark plugs and one and six were very wet, indicating no spark.
Check all the connections, latest sport plugs across the head and spin the motor and they all are sparking. What the fuck?

I noticed that one and six has a slightly weaker spark than the others. But for now, she is hitting on all six so let's adjust the fuel air mixture.
I made a tool to access the jet for the inner cylinders.

Unfortunately, the only carburetor that has response to the fuel idle Jeff being adjusted his number three.

Carburetors one and two the jet can be fully inserted or fully out and no change in engine response.
Carburetor three, running it in the engine, stumbles. Turning it out it RPM raises.

Three turns out seems to be the sweet spot. This is for both adjustments on carburetor number three.
 

I thought perhaps because I had not done a running securization perhaps the fuel air idle circuit was not yet in play.
So I performed a rough running synchronization. Here are the results.

At this point, the bike is idling very well, and is very responsive to throttle. I am kind of debating whether to mess with it or just let it be.

I pulled the sparkling plugs. Here is the result. One through six left to right.

I don't know why, but the picture makes the plugs. Look better than what they are.
Number one looks a bit oily, to a bit sooty, three is wet, four is sooty, five and six look great.

Is it a coincidence that five and six had the carburetor that adjust correctly?

Decided to talk to Herb Varin at C&H Cycle. He was very nice, spent about an hour with me discussing what it might be. 

Herb suggested that I start first by lowering the fuel level in the float bowl by 2 mm. When I set the level, perfect service manual, it was using brass floats, not OEM. Not sure if this matters or not, probably not.

Herb's theory is that a little bit of fuel is dribbling into the Venturi and into the combustion chamber. Even though it's just a little bit, it is much more than the idle circuit provides,  rendering the circuit in operative.

I think this is worth a try.

Additionally, I am going to replace the emulsifiers that wiredgeorge provided, the ones that had to be turned down to fit.

My theory is that fuel might be passing from the float bowl and oversaturating the pilot jet circuit.

My plan of action is to perform the following steps.

1. Remove carbs
2. Lower fuel level 2 mm
3. Replace wiredgeorge brass with either Damien Ding or Keyster.. I have both available.
4. Drop the needles one clip as this bike has always run rich. Without the airbox, these plug should be running lean, and they are not.
5. Replace fuel inlet valves.
6. Hope for the best.

Fortunately, we have a storm coming in and this is work. I can do indoors.

Persevere to persevere!

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2025-02-04 Carb Rebuild Rev2

"If you do not succeeded, try try again."

'The definition of insanity is doing the same thing over and over and expecting a different result."

I am starting to wonder which one of these quotations apply to me right now.

After the first rebuild, carburetors wanted to have no idle circuit adjustment. Spoke to Herb Varin. He suggested lowering the fuel level 2 mm.
Here is what I found after pulling the rack. Wet intake, boots, indicating either a fuel leak or too high of a level.

It kind of makes sense
. If I have fuel dribbling into the cylinders, it would overpower the idle circuit.

I decided to install all new brass. I had bought two kits from Damien Ding and I have one kit from Keyster.
The brass that was installed by wiredgeorge, the emulsion tubes have been grown down to fit the ID of the carburetor.

This is pilot jet number one.

Pilot jet number two. The camera angle is a bit off, but you can see the
jet is clear and that both jet diameters visually are the same diameter.

The new diaphragms from Zed-Parts have settled in nicely. No wrinkles!

New fuel inlet valve. I would prefer the needles to be some form of rubber metal.

New idle jets came protected with plastic.

The overall quality of this kit is very good.

Main jet number one.

Note to self, be sure to install the washer.

Main jet 2.
Beautiful.

Idle jets installed.

New emulsifier tubes. On carburetor number one, the left-hand side is snug.
A bit tighter than I would like, but no need to perform machining!!

Installed.

Both are seated, the picture makes it look like the right hand side is a little bit taller, but it is not.

Or is it?
I have to look again.

OK, then, no wonder the main jets have not yet sucked the emulsifier tubes down to the seat.

Main jet number one.

And number two.

Fuel inlet valve and clip.

Ready for the float bowl.

Choke plunger.  OK, enriching system plunger for purists.

Old and new.

One final look.

Nice and clean.

Still need to lower the fuel level by adjusting the float.

This completes carburetor number one.

Next step, carburetor number two. Carburetor number three seems to be working so I'll leave it alone.
If it ain't broke, don't fix it.

A pile of brass.