Tilly main jet removal..do you need a method?

[tbirdtbird]

So does a Tilly main jet ever get seized into the body? Nah...but for those rare times that they do, here is one method which might work for you.
I developed this method based on the way I get the large flathead field coil screws out of a starter or generator.

In the pic, there are several wood blocks to the rear of the vise arranged to get the proper tilt to the carb so that the drain plug hole (and thus the main jet threads) are parallel to your bench top. The front of the pic shows the vise jaw (with some white paint on it), and then a 3/8 steel plate drilled 1/8" deep to accept the end of the screwdriver bit to keep it from walking all over the place. 1/4 inch plate would work, too, there happened to be a chunk of 3/8 lying next to the vise. The bit is for my small rechargeable impact driver but there are any number of similar bits out there. I placed a 5/16 box wrench over the bit before I took up the slack in the vise. The orange strap is a ratchet strap to keep the carb body from riding up in the vise due to the irregular angle. You cannot hold it down sufficiently by hand.

Before starting, apply Kroil or your fav solvent and let soak in overnight. Then turn the carb over on a wooden surface and with the proper sized screwdriver in the slot of the jet, whack the end of the screwdriver a few hard times to apply some percussion to the corrosion and deepen the slot in the brass, especially if someone has mucked around with the jet before you got there and chewed it up.

The problem, of course is 1) the zinc body likes to corrode the jet in place and 2) you cannot hold a screwdriver tight enough into the slot without it camming out and chewing the slot all to hell. 3) you can't use heat on a Tilly.

Tighten the vise up pretty solid so that you can first break the corrosion without damaging the slot. Even with the vise quite tight, the jet will still turn a little bit. I used a short length (6") of 1/2 inch pipe over the 5/16 ignition box wrench for some extra leverage. Be sure to go back and forth as you are turning, not just out. As the jet threads slowly loosen and you are able to back the jet out a tiny amount, loosen the bite the vise has on the bit (back the vise off as slowly as the jet is unscrewing).

It worked for me, hope this helps. You will need to chase the 3/8-24 threads, of course, after jet is out. If this doesn't work the only other way I know is to drill it out, but this requires great care.

[Mike V. Florida]

Adding this to my how tos.

[Growley bear]

This is something to keep in mind. Great idea, thanks.
Chet

[Wick]

I throw mine in the oven and heat it up and jet comes out.. Not worried about the heat. The Tillys are warped anyway. After im done I put hose clamps on the body and back in the oven. When I can hold the carb up to a light without a gasket between the body and top and not see light i'm done.

[Patrick L.]

No mater what, sometimes it just won't back all the way out and needs to be drilled out.

[tbirdtbird]

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you are right they are usually warped but these 3 were totally unwarped, best I have seen, and I wanted to mess with them the least I could.

The oven trick sounds good I'll have to try that next time...but on the grill for me...fumes in the house are verboten !!!

[Ron in Quincy]

I have used the same method as WICK for a number of years on warped Tilly.

On those Tilly that are in good shape I first try the normal removal without heating in the oven.

[Wick]

If all else fails I get out the left handed drills and then it IS comming out!
I've used a hand impact driver also.
Also if you remove the lead plugs from the body they can be replaced with SplitShot for fishing line or Bird Shot. Just set it on the hole and give it a tap!
Another project;
Im making a jig to hold a tilly on my mill so I can just cut them smooth.