Cleaning the Pilot Circuit

[ottoguy]

Does anyone have a diagram of the Pilot Circuit to make sure I'm cleaning the right stuff? I have already read carbs 102, and already followed it. All of the jets have been soaked. I didn't soak the carb bodies. Is that the only way to clean the pilot circuit? Does spraying cleaner in the pilot jet opening work well? I have heard about using wire to clean the circuit but don't know where I'd be using the wire.

Also is there a picture guide that would help ID by the needle what type of jet kit is in a bike?

This is a 1999 750 by the way.

[Kreylyn]

Spray cleaner helps to remove soft and liquids on the carbs. It wont be as aggressive as needed to remove the hard stuff like a really dried on varnish, at least... not as quickly as it would need to for the cleaner to clean the ports by spraying through them.

The carb dip allows for the dip solution to get in and soak into the hard dried out varnish and other deposits. This dissolves them, softens them, or loosens them up.

Then... the spray cleaner and compressed air blows it all out nice, clean, and dry.

There are multiple ports and connections for those ports in the idle circuit. The pilot air jet crosses with the a/f screws, with the pilot jet fuel line, etc... Spray forced into one hole will always take the easier route out another hole... the clean one.

I suggest using the dip for each of the carb bodies.

Krey

[jamesm113]

Is carb dip anything different than submerging carbs in regular carb cleaner?

I've cleaned my carbs with carb cleaner spray & compressed air countless times, but I think the pilot circuit is still dirty, as the A/F screw doesn't seem to affect how the bike runs, and I can't ever get the idle set at 1800 RPM for a carb sync- it starts hang/revving to 2k+, meaning it's still lean, even though I have #15 pilot jets (stock 12.5) and 2.5 turns out on the mixture screw.

[Kreylyn]

Is carb dip anything different than submerging carbs in regular carb cleaner?

I've cleaned my carbs with carb cleaner spray & compressed air countless times, but I think the pilot circuit is still dirty, as the A/F screw doesn't seem to affect how the bike runs, and I can't ever get the idle set at 1800 RPM for a carb sync- it starts hang/revving to 2k+, meaning it's still lean, even though I have #15 pilot jets (stock 12.5) and 2.5 turns out on the mixture screw.

Krey

[steves]

Half the point to regular carb cleaner is that it's propelled. The Berryman stuff is awesome been using it for years.

[jamesm113]

So this berryman stuff is a lot better than regular carb cleaner spray? Where can I find this?

[arsenic]

Autozone

[Kreylyn]

So this berryman stuff is a lot better than regular carb cleaner spray? Where can I find this?

Any auto store can get it, probably has it on the shelf. Avg price is $19.95 per can.

The simple of it...

The dip disolves the varnish and other dried on sticky coating that causes the problems.

The spray cleans the residue from the dip when you pull the parts out.

The compressed air blows the spray off and dries the part.

The spray will not remove the dried on stuff.

Compressed air will not remove all of the dip.

Don't skip steps, use all 3.

The gallon cans will hold generally 1 carb body at any given time. Never leave a carb body in the can for more than 24 hours tops. The solution will leach things out of the metal if left in too long and cause problems.

Krey

[phantasm]

Be sure to COMPLETELY disasemble carbs. Any rubber seals left in will be trash after dip

[jamesm113]

Okay, I found the stuff at o'reilly's for $19.99. I think I'll leave each body (stripped of rubber) in overnight. I really hope this works, I've been getting very frustrated with the lean issues I have been having.

[steves]

BTW, the berrymans instructions say to wash the part in warm soapy water after dipping.

So I always add a water wash after dip, before spray.

Okay, I found the stuff at o'reilly's for $19.99. I think I'll leave each body (stripped of rubber) in overnight. I really hope this works, I've been getting very frustrated with the lean issues I have been having.

Cali Berrymans... not as good as 49 state Berrymans FWIW.

[jamesm113]

Can I take out the air jet? #22 in the picture. I think it would help me clean it better, but I don't see it as part of carbs 102 or in the haynes manual i own.

[Kreylyn]

Can I take out the air jet? #22 in the picture. I think it would help me clean it better, but I don't see it as part of carbs 102 or in the haynes manual i own.

It can be removed. Make sure you have exactly the right size screwdriver in there or it will crumble the jet on you. Replacements are not overly expensive, but ...

Krey

[jamesm113]

Grrr, it is still running lean.

I:
Disassembled the carbs, removed every jet (including the air jet), dipped each carb and its jet one at a time in Chem-Dip for 24 hours, dipped the carb in a bucket of warm water, then proceeded to use spray carb cleaner, then used compressed air to clear everything out. I really concentrated on the pilot circuit. I let the carb dry, then reassembled everything back together. I set the AF mixture to 2.5 turns out and installed brand new #12.5 pilot jets.

Checked float height w/ a set of calipers and set the #4 carb to 13mm, the other 3 carbs were in spec. I measured from the middle of the carb body to the highest point on the float. Bench tested the float needles with the gas tank on prime, 2 & 3 leaked within 15 minutes, took the float seats out on those two and tried again. Bench tested on prime for 24 hours, no leaks.

Started the engine up & let it warm up for a few minutes, rev'd the throttle, and the revs were hanging. Tried 3 turns out, the revs were still hanging. I sprayed the intake manifolds and the airbox/carb junction with carb cleaner, the RPMs did not change.

Over the past year, I've replaced: the breather hose, the vacuum ports caps, intake manifold gaskets, the #4 carb to petcock hose, AF mixture o-rings, emulsion tube o-rings and more i can't remember right now. I'm almost positive the airbox is stock, I attached a picture in case it's not.

Please help!! Thank you!

[arsenic]

That's the air filter that goes in the air box, and yes, it's stock. Does the drain hose on the air box have a cap on it? Did I say that already?