How to change the jets without damaging the whole assembly

Chromaphase

Chromaphase

True Classic
Hello everyone.
Its a small and maybe stupid question.

I ordered new jets for main and primary. As well as new air corrector.
I can take off the air corrector just fine but the jet on my original assembly are stuck really.
I do a spare assembly from another carb that are stuck as well. On this one I tried to pry it with a tool and I did worse than good.

Thanks for your help, each time Im searching about stuck jets, its usually the whole assembly stuck inside the carb. Not my case.
 
The emulsion tube is installed under the air correction jet; the main jets are screwed in at the bottom of the float bowl.
I have had good luck sticking a small screwdriver into the emulsion tube and rocking it back and forth to loosen it.
 
Jefco said:
The emulsion tube is installed under the air correction jet; the main jets are screwed in at the bottom of the float bowl.
I have had good luck sticking a small screwdriver into the emulsion tube and rocking it back and forth to loosen it.
Click to expand...
You're confusing a DMTR/DATR style carb with other models of Weber like a DMS/DGV etc... the main jet does not screw into anything in a DMTR/DATR carb, it simply pushes into the base of the emulsion tube, the air corrector pushes onto the top... it's the air corrector that has the screw thread to hold the whole assembly into the carb body.

32DATRA 8-100 page 1.jpg


for the OP, if the jet is stuck, you need to hold the emulsion tube in a way that doesn't mar or mark the exterior, or crush the tube... and grab the jet with a pair of pliers and twist... it will come out.

Not sure why you want to replace any jet with a different jet ad hoc, the standard carb has its jets sized well for a standard engine. If you think adding more fuel will avail you more power ... hate to burst your bubble but ... that's not how it works on a four stroke petrol engine.

yes the standard primary main jet can benefit from going up one size from 110 to 115 in the standard 34DATR, as the primary does run a little lean, but just because one size up is good, does not make two sizes up better...

SteveC
 
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As Steve says, I put the emulsion tube in my vice with some kind of padding and use a pair of pliers to gently twist and pull the jet off it.
 
Brass jets are easily damaged by pliers, poking with a screwdriver and similar...
Get a set of ER20 collets like these:
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12Pcs Spring Collet ER20 Set For CNC Milling Lathe Tool Engraving Machine | eBay

<li> Fitment：</li> <li>For CNC Milling Lathe Tool & Workholding Engraving Machine</li> <li> </li> <li>Description：</li> <li>-Model:ER20 -Condition: Brand New -Material: High Grade Carbon Steel -Run-Out Tolerance: 0.015mm (0.0006") -ER20 12Pcs...
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And a ER20 collet holder like this:
www.ebay.com

US Stock C16 ER20A 100L CNC Lathe Milling Holder Shank Chuck Collet 16 x 100mm | eBay

US Stock C16 ER20A 100L CNC Lathe Milling Holder Shank Chuck Collet 16 x 100mm.
www.ebay.com

Set up the proper size ER20 collet in the holder for the jet to be removed. put the jet to be removed into the collet, tighten the collet nut to hold the jet to be removed. Pull on the collet holder to remove the jet. This method greatly reduced the possibility of damaging the jet, emulation tube and all related.

Bernice
 
And here I was going to say that be sure you grab the jet with the pliers so that you don't scar the jet size number.
 
I keep a piece of soft suede leather (same stuff I use for the bottom of jewelry box drawers when I’m doing my other hobby, woodworking) around to pad the jaws of the pliers, and hold the jet in the open part of the jaws. Haven’t damaged one yet,
 
The real fun is the opposite situation where the main jet sits too loose in the emulsion tube and when you pull the tube out the main jet is still sitting in the well.
 
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