Removing air/fuel mixture screw to back access the pilot circuit and jet for cleaning

[jfman]

Hello venturers

 

Sorry for yet another carb thread/question.

 

Say you suspect you have a clogged pilot jet on one carb and that makes one of your cylinders unhappy at idle.

Say you also happen to be a lazy person and you would like to avoid pulling and dissasembling the carbs.

 

Could you remove the air/fuel mixture screw on that one carb and then inject cleaner into the circuit with a straw or syringe. Then you would let it sit for a few days to let your cleaner work its magic. Afterwards you would blow a little bit of compressed air into the circuit by way of the exposed hole from the missing a/f mixture screw to hopefully dislodge the crud in the actual pilot jet.

 

Finaly you would flush out the carb bowl.

 

All of this while the carbs are on the bike.

 

What do you guyz think of this idea?

 

I plan to try it on my 1988 venture and flush the bowls also.

Edited November 20, 2019 by jfman

[MiCarl]

I have done that with just compressed air. I have maybe a 10% success rate.

 

If compressed air won't do it the carb cleaner won't get to the clog anyway.

[BlueSky]

I think I would try removing the idle mix screws and spraying carb cleaner in the hole. Be careful because it's really hard to get the o-ring out. you will think it isn't there but it is and carb cleaner might ruin it. Your best try might be to use cowpuc's method. Do a search and read about his method. An animal syringe injecting carb cleaner through the drain. You need to get the details from him because he explains how much to inject.

[tz89]

remove the air/fuel mixture screw on that one carb and then inject cleaner into the circuit

 

My mechanic did that to save me from a complete rebuild when I got my 89. It was running on 3 until then. I put new diaphragms on afterward, gave it sync, and it ran like the sweet beast these bikes are.

[SpencerPJ]

I think I would try removing the idle mix screws and spraying carb cleaner in the hole. Be careful because it's really hard to get the o-ring out. you will think it isn't there but it is and carb cleaner might ruin it. Your best try might be to use cowpuc's method. Do a search and read about his method. An animal syringe injecting carb cleaner through the drain. You need to get the details from him because he explains how much to inject.

 

 

See post 24 in this link.

https://www.venturerider.org/forum/showthread.php?128318-How-to-use-Seafoam/page2&highlight=cleaning+carb

[cimmer]

You can also try this method. I have used it in the past on my bike and have had good luck with it.

http://vmax.lvlhead.com/tips/shotgun.htm

 

This is for a Vmax but the Venture has the same basic carb layout.

 

Good luck..

 

Rick F.

[Prairiehammer]

 

Could you remove the air/fuel mixture screw on that one carb and then inject cleaner into the circuit with a straw or syringe. Then you would let it sit for a few days to let your cleaner work its magic. Afterwards you would blow a little bit of compressed air into the circuit by way of the exposed hole from the missing a/f mixture screw to hopefully dislodge the crud in the actual pilot jet.

 

 

Injecting cleaner into the pilot screw (air/fuel mixture) orifice won't get cleaner to pilot JET. The path of least resistance would send the cleaner straight into the carb bore.

 

What you CAN try is to inject cleaner into Pilot Air jet #1 . That path is a relatively straight shot to the pilot jet.

 

Edited November 21, 2019 by Prairiehammer
Added carb schematic

[jfman]

Injecting cleaner into the pilot screw (air/fuel mixture) orifice won't get cleaner to pilot JET. The path of least resistance would send the cleaner straight into the carb bore.

 

What you CAN try is to inject cleaner into Pilot Air jet #1 . That path is a relatively straight shot to the pilot jet.

 

https://www.venturerider.org/forum/attachment.php?attachmentid=118087https://www.venturerider.org/forum/attachment.php?attachmentid=118088

 

when looking at the mouth of the carb after removing the airbox, is it the orifice with the large brass jet or is it the other orifice close to it?

[Prairiehammer]

when looking at the mouth of the carb after removing the airbox, is it the orifice with the large brass jet or is it the other orifice close to it?

 

The pilot air jet #1 is the large brass removable jet.

[jfman]

The pilot air jet #1 is the large brass removable jet.

https://www.venturerider.org/forum/attachment.php?attachmentid=118173

 

 

Thanks a lot!

 

Carbs are now off but wanna make sure i clean it correctly.

 

Btw the pilot on the suspect carb was massively clogged.

[Prairiehammer]

Thanks a lot!

 

Carbs are now off but wanna make sure i clean it correctly.

 

When you remove the jet block from the carb body, shoot some spray carb cleaner through the various orifices, followed by compressed air.