Pilot Jet Removal/HELP

[geneborg]

Ref. my thread of 7/4/7 where I broke the pilot jet tower. I now have obtained a used rack of carbs and have gotten 3/4 of the pilot jets loose but the 4th had the slot burred and will not loosen. Am a bit paranoid after breaking the towers. Did some more research on the threads. Which I should have done earlier.
If I have to drill it out the following was recommended:
1) Use a 1/8 drill
2) Then a 5/32 drill
3) Then run a tap to clear the threads (5mm x .8 tap) (stnd 5mm tap)
If any comments on this drilling routine please speak up.
My question is, once you have drilled out the jet then what? ie how do you then remove the jet? My previous mistake was using too big an easy out and splitting the tower. The jets are so soft that the easy out just drills into the jet.
OR even better does anyone have any good ideas on how to get the jet out without drilling and somehow grabbing the jet with the burred screwdrive slot.
I will be much more patient this time and use penetrants for however long as necessary.
HELP

[TopCatGr58]

Hey Gene,

A little more searching could have also revealed other tips about getting a reverse cutting drill bit, that way when you are drilling, the vibration and the bits biting into the jet quite often gets the jet turning and removes it as well! Also, chucking the bit into a drill press to help ensure a straight shot/path into the jet and carb body when turned up side down...a possible drill press vice, or clamps to secure the body, and then you can even just turn the bit by hand. My drill press won't turn in reverse, but a hand held one is quite often reversible!?

You're right, the case aluminum isn't that strong, and I would have reservations at trying to drill the thing out, and then trying to use a tap to clean up the threads!

You might also try a butane torch or heat gun to heat up the carb body to get the aluminum to expand around the brass jet, may help to break the varnish/gum or corrosion that has fused the jet to the body!?
Good Luck!
T.C.

[geneborg]

Thanks for always being there

TopCat, I appreciate your responses to my questions and if no one else replies I can depend on help from you. Now that you mention it I vaguely remember mention of a reverse cutting drill bit. This reminds me of the right mirror reverse thread. I learned by breaking it off and then realizing it had reverse threads. When I drilled it out with a regular drill bit the remaining broken piece spun out on the drill bit.

[oseaghdha]

The end of the jet is smaller than the threaded part, so once you drill through it will spin.
If you are careful and hit the middle, the threads can be picked out cleanly. Take it easy and go slow.
Make certain that your drill is close to the minor diameter of the thread, that's the part in the bottom of the "Vee" on the JET. NOT THE THREAD OUTSIDE DIAMETER
Compare with one you sucessfully removed.

Sorry if I am over explaining, I have no idea of your skill level.

If you start with a smaller drill it will tend to follow the jet diameter. So, maybe an .0625. The next size .125 will follow that hole, and so on until you reach the proper size.
Watch out because brass is grabby on drills, tries to suck it in.

I am unsure of the specific drill sizes, don't have my charts handy.

When you are done, you should have the end of the jet out, and see only the threads left in the hole which will need to be picked out with whatever tiny tool you can come up with. Follow up with the tap to clean out the threads. Don't recommend using the tap to remove the leftover threads.

CAUTION:
If you go too big or get off center you will destroy the threads in that hole, which means you trashed another carb. This is a fairly difficult operation.

I had that one %%$%#$&* that would not come out and used this method sucessfully.

[newc4]

Removing pilotjets

When jets are stuck in place I found that dowsing the jet with penetrating oil followed by using a propane torch to heat up the body around the jet burns off the gunk and with the dissimilar metals, loosens the jet. Then it comes out with the screwdriver or easyout no problem. This has always worked for me.

Darrell

[COOL TOM]

Dremel

Use a Dremel with a small cutting tool and grind a deeper slot in it for the screwdriver, then like they said heat it up CAREFULLY don't want to melt the alum. That is the way i got a couple out of my 80SG. I have a set of diamond cutting tools for the Dremel that i got from Harbor Freight

[SFerinTEXAS]

STUCK JETS

I believe you should should just get the smallest easout made. think its a #1 size. Fits right in the jet give a gentle tap or two and should come on out. I've done this about eight times and always worked for me.

[fredintoon]

Try this

Hi Gene,
here's what has worked for me to remove a jet with a fritzed screwdriver slot.
You gonna need a drill press, a bench grinder and a screwdriver you ain't fond of.
Regrind the screwdriver to be a perfect fit in the jet's slot. Cut the handle off and put the blade in the drill press chuck. Put the carb body on the drill press work plate and hold the screwdriver blade hard down into the wrecked slot using the drill feed handle. Keeping the pressure on, turn the chuck backwards by hand to start the jet turning.