Mikuni pilot jet

So, I'm trying to get this 550 Seca going.

Carbs were dirty, but not catastrophically so. I cleaned the bowls out, took out needle valves and starter valves, cleaned nozzes and pistons. So far so good. Yesterday I got the parts I was going to replace (thanks, Chacal) and thought I was going to put it back together. Then I decided to make sure pilot jets were clear.

Three of the carbs are OK. I sprayed then out, blew air, if I fill the hole with carb cleaner it drains. The fourth one I can't get unplugged. I've sprayed it, I poked it with a guitar string, I blew compressed air through it. No dice. I left the hole filled with Chem-dip overnight and this morning it was still full. I don't want to dip the whole thing because I don't want to mess up the seals.

What else can I try to get it clear?

 

Remove it and get medieval with it, pliers and a blow-torch...... 8)

Once it's out you can throw just the jet into some solvent to loosen up the varnish. Or just buy a replacement jet.

 

As I understand it, you got the jet out but can't clear the hole. I've heard of folks using a very tiny drill and turning it by hand to clear the passage. I haven't tried it on something this small, but I did something similar to clear the pcv passage in a throttle body. Make sure the drill bit is smaller than the passage and go slow. Or just keep jabbing it with the piano wire and I suspect it will eventually give. Can't be concrete!

 

Most guitar strings are too big for the hole in the pilot jet. I use a single wire from a small(tooth brush) size wire brush.

 

JP did you ever get that pilot jet out to clean it. I'm working on some 550 carbs for another member and I had to drill it out and run a tap through to clean the threads out. I just got new pilots from chacal because the screw driver slots were in bad shape.

MN

 

I did. Berryman carb dip, plus spray cleaner plus compressed air did it.

 

Since I made mysefl think something else was wrong I pulled the carbs again and got the pilot jets out.

Three came out just fine with a screwdriver ground to size. One had no slot. I'm assuming someone prior to me ripped it clean off.

I checked around for small EZ-Outs and the smallest one I found looked too big. So, I got a large stainless steel deck screw, ground the point to a sharp flat spear, put it on the jet and gave it a couple of whacks, then turned it with a screwdriver. The jet came right out.

Looks like it wasn't as clear as I thought it was, anyway, so I will use one of the jets I've had soaking in Berryman for a couple of days.