Can someone tell me which screw is the correct one?

RepoDraghon

So I figured I'd take a super super close look at all the screws on the carburetor that's already installed in my truck and knowing from MazdaMitch's videos there's an air fuel mixture screw but what one is it on this particular carburetor? There's a small screw and a bigger screw, the smaller screw is facing towards the engine and the bigger screw is facing away from the engine... That being said both of them are screwed in all the way but I don't see any other screws really that really don't lead to anywhere and they're both about the same height on the carburetor...
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Cusser

RepoDraghon There's a small screw and a bigger screw, the smaller screw is facing towards the engine and the bigger screw is facing away from the engine... That being said both of them are screwed in all the way

Repo - those are the jet holder screws. The larger one on passenger side is for the primary idle jet. The smaller one on the driver side is for the secondary idle jet. Each seals with a small O-ring, don't let that fall if you remove these to clean out the jets. I put down a white towel to catch any jet holders or O-rings in case I drop something.

My primary Weber idle jet is 60, and secondary idle jet is 50.

RepoDraghon

Cusser I just don't see any other mixture screws possible on this... The only other thing is for the idle rpms...

Maybe this one?

MazdaMitch

RepoDraghon this one you're looking at is the fast idle adjustment.

RepoDraghon

Well it was super super super super loose like 4 or 5 full rotations... I tighten that one up and backed it off one and a half turns and guess what no more backfiring... Still could use more power though so I'm probably still running lean...

MazdaMitch

RepoDraghon if you're talking about the fast idle adjustment that's not at all how you adjust that you adjust that while it's running when it's cold.

Why don't you take the time to go through the videos on my YouTube channel there's even a playlist called carburetor and emissions.

You can't help but learn something from the videos.

RepoDraghon

MazdaMitch I would but remember you guys are saying that this particular carburetor is not a real Weber and I have noticed that things are not in the place that they're supposed to be...

MazdaMitch

RepoDraghon it's just a clone everything is in the same place. You would understand the clone vs genuine if you watched the video on that.

RepoDraghon

MazdaMitch I watched it again, I must have missed the Mixture Screw part, it's literally the next thing after the Idle Screw... Yes, mine has that too but it's blocked by the AC lines, but since the AC line is fully broken now, I might as well remove them...

Update: adjusted the mixture screw as indicated from the video, good news is acceleration is now really great as before it kind of felt like it bogged down before accelerating rapidly but now it does it just fine, but then again I probably have to adjust the idle screw now... Bad news 5th just still just does not have any power... I cannot maintain speed and fifth... There will be days where it runs perfectly fine in fifth but the majority of days there's just no power there...

MazdaMitch

RepoDraghon There are no AC lines anywhere near the carb, what are you referring too?

RepoDraghon

MazdaMitch these black AC lines with the 1 electrical wire, tbh I cant find my stubby screwdriver and all my other one are too long, so technically they aren't in the way but it is hard to get to...

Cusser here are more pics and videos

Video 1
Video 2

Cusser

Pictures, pictures, pictures needed !!!

MazdaMitch

RepoDraghon
Video 1-2

That think is struggling.

You need to get an electric choke. Choke is highly effective and needed on start up.

But first you need to take the carb off, sand the adapter plates flat, used permatex hi tack on new gaskets, and get the carb mounted and secured properly. Thats just an vacumm leak you have now.

Cusser

RepoDraghon here are more pics and videos

I watched your videos. To me, first thing is remove the carburetor and adapter plates, sand them perfectly flat using a sheet of glass, then install properly using Permatex Aviation on the gaskets and blue Loctite and correct torque.

Second thing would be to get better linkage and an automatic choke.

MazdaMitch

That is not the stock setup for AC lines, thats some aftermarket stuff there.

RepoDraghon

MazdaMitch yeah, when I get the money... If I get the money... Any ideas on the lack of power and fifth? Is it the vacuum leak or is it still just not enough fuel?

MazdaMitch

RepoDraghon

Hard to say over the internet.... Could be... could also be the timing, the vacuum advance, the float level, the carb itself, on and on.

RepoDraghon

MazdaMitch well I assume if the carburetor is loose like it is maybe the distributor wasn't tightened down properly either...

RepoDraghon

Cusser yes those marked is what I was saying that I know now. The idle screw I knew was the idle screw however I did not initially see the fuel mixture screw when I took those initial pictures at the top of this post... Maybe you can tell me, this spot that has the black manual choke, do I just need to replace that part with the electric choke or do I have to replace that whole entire metal ice cream cone shaped body as well? If I don't have to replace the whole thing do you think that I can remove it and place it on the actual Weber and have it work too? If that's the case then I might just get a rebuild kit fix up the Weber and install that instead...

Cusser

RepoDraghon Maybe you can tell me, this spot that has the black manual choke, do I just need to replace that part with the electric choke or do I have to replace that whole entire metal ice cream cone shaped body as well?

I would guess that the mounting for the black part would unscrew and the electric choke parts could be screwed on. That would be my guess, and make sense for manufacturing. But I don't know for sure, perhaps someone here with hands-on experience with this can post.