Best way to get screws out of carbureator

[Lothsahn]

I rebuilt the carburetor in my 1996 GTS, and it went well except for trying to get the internal screws out of the carb. Especially the two large screws were *really* stuck in there. I got a set of JIS screwdrivers, which couldn't even begin to budge them. All they did was damage the screw heads and flex the screwdrivers (I suspect the quality was not good on them). I ended up removing them with an impact driver and phillips bit, which removed one, but just destroyed the other. Had to use an ez-out to remove the other screw, which *thankfully* worked.

I'm now looking to rebuild the twin carbs in my 1996 GTX, and I'd like to avoid a repeat of that situation. Does anyone have any good recommendations on how I can remove the screws in my carburetors when I go to rebuild them?

 

[Mekanix]

JIS Bit and an impact gun with alot of pressure has been my only way. Or a little heat from a pen torch

 

[mikidymac]

Vessel JIS screwdriver fro Amazon works 99% of the time. The other 1% an impact screwdriver.

 

[Kwik_uk]

Vessel JIS screwdriver fro Amazon works 99% of the time. The other 1% an impact screwdriver.

Exactly this ^

If it’s being a pain in the ass, use I high wattage soldering iron to heat the screw up. Doubt it’ll need it, just use the right tool

 

[Lothsahn]

Thanks for the responses. I've bought a vessel JIS impact screwdriver with bits and hope that will solve all 100% of my cases.

I would strongly recommend people avoid the following tools, as they did not work well at all for me, and the steel in the screwdriver shaft was somewhat flexible and even began to twist as I turned the screwdriver: Hozan JIS-4 JIS Screwdriver Set (Amazon)

 

[mikidymac]

The carbs take a JIS #2 for everything except the metering block mylar check valve and that tages a #1.

 

[SabrToothSqrl]

i thought someone on here sold a stainless hex kit to replace all the JIS screws w/allen heads or something a while back..?

 

[mikidymac]

i thought someone on here sold a stainless hex kit to replace all the JIS screws w/allen heads or something a while back..?

Correct, it's OSD but I think it's just the external screws?

 

[artr]

I had similar problems removing the screws. If a screw head got damaged, I went out of my way to get the original Mikuni screws even though I found stainless ones that fit the 2 larger screws. I thought the original screws would be of the same material as the carb part they go into to avoid corrosion problems if the screws are not removed for a long time. Has anyone used stainless screws for the internal ones without future issues? Has anyone tried a little anti-seize on the screws without future issues?

 

[mikidymac]

If you keep water out of your fuel you will not have any corrosion issues. The only carbs I have had issues with are ones that either sank and sat with water in them or one that someone left the drain plugs in and it filled up with rain water. The screws are steel and the carbs are aluminum so you can get corrosion even with stainless.

 

[Flightjunkie]

Hi.

I use Tef Gel on all my fasteners in the Marine environment. Especially important with dissimilar metals.

I live in Hawaii. So, galvanic corrosion is a big problem.

 

[val-e-vue]

I rebuilt the carburetor in my 1996 GTS, and it went well except for trying to get the internal screws out of the carb. Especially the two large screws were *really* stuck in there. I got a set of JIS screwdrivers, which couldn't even begin to budge them. All they did was damage the screw heads and flex the screwdrivers (I suspect the quality was not good on them). I ended up removing them with an impact driver and phillips bit, which removed one, but just destroyed the other. Had to use an ez-out to remove the other screw, which *thankfully* worked.

I'm now looking to rebuild the twin carbs in my 1996 GTX, and I'd like to avoid a repeat of that situation. Does anyone have any good recommendations on how I can remove the screws in my carburetors when I go to rebuild them?

I found the best results while soaking with penetrating oil and then using the manual impact driver with light taps. The heads of the screws can't take much, so many small taps works the best.

If the screw head turn to mush, then I go to plan B:
Drill the screws out using a 3/32" bit deep enough to drive a torx T10 bit into the hole. Don't drill very deep because you don't want to snap off the screw head. You just need enough depth for the torx to get grip. If you do snap the head off, you can probably remove the screw with small vice grips.

The T10 will grip the screw very well and you will get it out. You can order some new screws to replace them. M4x14mm 316 Stainless Steel Flat Head Phillips Machine Screws are a perfect replacement for the the manifold.

P.S. You can buy JIS bits for your impact. They fit a little better, but it's still import to use lighter hammering... tap, tap tap...