Yes, you need the correct machined thick spacer under the carb, its in the conversion kit.. It will never run properly without it.
Gasket each side of the spacer too, the 2 hole plate, ensure the slot on the plate matches up with the slot on the carb base. I bet this is 90% of your issue. Gasket is critical and must natch the plate, 2 holes manifold side 2 holes and a slot the carb side, do not try to use a single hole oval gasket on the carb side. This plate is what controls the vacuum for the ignition as well. Its tapered bore too, not a straight bore spacer.
Vacuum at idle should be around 22 to 24", you need the correct plate, this is in the conversion kit you should have bought.
Is it jetted for the engine? Float level Correct? What's the history of the carb?
Correct gaskets are a must as there's a couple of tiny air bleed holes and vacuum slot you need to ensure dont get blocked. This is why you get the conversion kit, its all there and correct. Total install with the kit is about 30 mins, remove old carb, fit new carb with the conversion kit and turn key. Tuning assuming the carb us jetted for the sane capacity takes about another 15 mins

Air screw sounds about right, if you are getting about a turn either way before the idle gets lumpy.But it will not tune right until its hot the citprrect base spacer on it.

As for the cold running, Are you using water?

 

carb and manifold have two bores.... not sure what is a "singular hole gasket" but maybe its just my english....

 

Thank you for the information. Have run my Ford 460 RV with and without spacers and with a square bore (single hole) carb base gasket for years so I thought I might be ok. I will get the adapter but it does not look like my carb has the vacuum port notch on the bottom. I was hoping it did and that is why it is running rich. My engine had a carbureto conversion done when I bought it, (webber carburetor (I think). I noticed it still has the EGR but it has the vacuum ports on it capped off. Is it important to delete the EGR with a plate? The PCV valve is run through a small air filter and then dumped into the fender well. Some say it is important to run that into the carburetor air filter. I have no idea. Here is a link to the carb I purchased on Amazon. https://www.amazon.com/dp/B07GJ8PS3R?psc=1&ref=ppx_pop_dt_b_product_details
Waverspeed ASIN B07GJ8PS3R Carburetor Carb for Toyota Corolla 3K 4K 1968-1978 21100-24034 21100-24035 21100-24045.
I have an 1989 Suzuki Sidekick 1.3L
As for the Susuki 1.3 running cold issue' I am running 50/50 mix antifreeze and I checked the thermostat in boiling water and it opened at 180 degrees as it should. It is the 1mm deep recessed thermostat with NO rubber O-ring around the outer edge (or anywhere else) and seats very snug. The spring is facing down into the manifold and the bleed hole is facing front towards radiator. I have heard someone say on a forum that he put the air bleed hole at 12 o clock facing the carburetor and his Suzuki started running at the correct temp. That doesn't make sense to me but who knows. The gasket and hose housing cover the thermostat outer edge slightly so I don't see how it coolant could be getting around it or causing the thermostat to float out of place. I even added some high temp RTV around it to be safe. I checked the thermostat housing with IR temp gun and confirmed it is running at about 120 degrees with cardboard covering the front of the radiator. I installed A new fan clutch even though the old one had resistance when I spun it by hand. Heater blows warm air as engine temp gets warm so I don't think I have a clogged heater core. Temp and heater worked great when I bought it. I have not air bled or burped the cooling system but I live in the mountains on bumpy up and down roads and the coolant has never needed filling. I am lost on this one. I guess I will try a new thermostat and raise the front end up 3 feet to burp the cooling system. Any body else that has solved this issue? Thanks so much everyone. I know enough to get myself into trouble but I am no mechanic.

 

There's a vacuum air bleed hole on the base of the carb, that lines up with the slot in the spacer

 

This is an old thread but I'm hoping 2013GV can help me with a similar problem. My '89-1.6L 8V has a Weber 32/36 conversion but I'm wanting to try a 3K clone. I'm posting pics of the Certified Machine spacer and gaskets, a spacer and gaskets that I bought off eBay, a pic of my intake manifold (that I think is off a 1.3 Sammi) and the base of the new carb. I understand about the vac port and why the CM spacer & gasket have the cutouts but you'll notice that on the new carb there are vacuum channels in both the primary and secondary. Also, you can see that my manifold has been hogged out to one large hole. If I cut the eBay spacer and gaskets to match the channels in the carb base, do you think it will work?

 

This is an old thread but I'm hoping 2013GV can help me with a similar problem. My '89-1.6L 8V has a Weber 32/36 conversion but I'm wanting to try a 3K clone. I'm posting pics of the Certified Machine spacer and gaskets, a spacer and gaskets that I bought off eBay, a pic of my intake manifold (that I think is off a 1.3 Sammi) and the base of the new carb. I understand about the vac port and why the CM spacer & gasket have the cutouts but you'll notice that on the new carb there are channels in both the primary and secondary. Also, you can see that the manifold has been hogged out to one large hole. If I cut the eBay spacer and gaskets to match the channels in the carb base, do you think it will work? View attachment 120871
View attachment 120871 View attachment 120872
View attachment 120872 View attachment 120873 View attachment 120873 View attachment 120874 View attachment 120874

Could you possibly measure the spacer, I heard that the samurai intake bores are 26&28 and on the toyota carb its 28&28, does one side of the spacer need to be bored out. How thick is the spacer and also how deep is the vacuum knotch. I want to do the 3k swap but i do not want to buy the certified machine kit since i only need the spacer from it, I already have the EGR delete and everything done since I have a Weber from a Yugo 65 currently, crap carb honestly, no adjustments, auto choke that works like shit. Thanks in advance

 

I have run a 3K instead of the OEM Mikuni for a while, but since you are only asking for 2013GV's help ill stay out of this

 

LOL…Your fairy godmother will look at you more favorably if, now that you’ve ‘made your point’, you actually give him some advice.

 

Let's see, sounds like he wants to hear only GV.... Dont want to be pushy, you know... not my style

 

@89Kickit2 I will admit that I know nothing about this. However this link goes through the complete procedure of installing the 3K carb into the Samurai….you may have found this already in your search. They are not modifying the spacers or gaskets at all, as shown on page 11. See if this helps:

https://static1.squarespace.com/static/5bd91ea3c3c16adac7b64c98/t/6511c5e6d3114b0a1bfd24eb/1695663604817/Rev+5+-+Toyota+3K+Carburetor+to+Stock+Samurai+Manifold+.pdf

 

Yes, I had downloaded those instructions from the CM site. Their spacer and top gasket are notched for vac on the primary but the eBay items sold by speedshop505 have no notches. From what I've gathered there are many different flavors of 3K clones out there on Amazon,eBay,etc. but Certified Machines supposedly gets theirs from a single vendor and apparently they all have the one vac channel. So my confusion since my 3K has two vac channels. The vac for the dizzy advance is drawn from the port in the secondary bore as shown below so I'm wondering what the others are used for:

 

@turboguzzi...LOL...My apologies. I didn't mean to slight you. After my septuagenarian self was done scrolling thru all the verbiage on my phone's tiny screen, I focused mostly on 2013GV's input. Is there a thread detailing your 3K experience?

 

^Close. It's ~.062mm less. So you are making the spacer from scratch? 3D printing? I'm close to just going ahead and try it but saw this thread and decided to maybe get some input first. My main concern is what effect the hogged out manifold will have.

 

I'll machine it from steel or aluminium, since I work with that stuff. Imo you should try the gaskets and spacer as is, if it works good, if not I guess you could make some adjustments to it, like cutting the vacuum port and getting the original 3k gasket. I really don't know what would work considering that hogged out manifold, maybe the spacer will make it the same as if the manifold wasn't hogged out.

 

Do you have a 3K yet? With the one vac notch on the primary? Also, If I'm not mistaken, the spacer is made of a phenolic material that helps insulate the carb from heat. Steel or aluminum might transfer too much heat...

 

I do have a 3k and the notch is on the primary, there is a couple of different versions of the 3k which might make some difference, some labeled 21100-24035, 21100-24034, 21100-24045, TOY-250 etc, so maybe that's the difference and why yours has the notch on the secondary yet most don't.
You carb has vacuum ports on the primary and secondary tho right?
I've seen many spacers on weber kits made out of some sort of metal, so I don't think it should be a problem with heat or anything really\

I just found a picture of a carb exactly like yours

 

@89Kickit2
my 3K didnt have notches like yours, with one holed screw fed air through a side tube , see last picture i posted.
i made a 4mm nylon spacer with a notch for the other screw. its an excellent material, fuel resistant and easy to machine, I use nylon all the time on inlet systems of racing motorcycle engines i build that get VERY hot, but being on a manifold that constantly flows cold air, heat shouldnt be an issue

My car is a euro model so originally with a mikuni carb, the stud spacing was exactly like in the 3K so no stud adapter was needed.

Your carb has already the notches in the mating surface, so you dont even need to make them in your spacer.

Had to build a bracket for the different position of the throttle cable and for the choke cable as the mikuni carb is auto choke.

Car started at first try with the 3K but felt lest responsive and fuel consumption was high, guess some rejetting was due, but as i overhauled in the meantime the original mikuni, that went back in. This how the mikuni looks like, its amazingly well engineered, but dotn thinkl youll find it in the usa

 

@89Kickit2 my 3K didnt have notches like yours, so i made a 4mm nylon spacer with notches for both screws. its an excellent material, fuel resistant and easy to machine, I use nylon all the time on inlet systems of racing motorcycle engines i build that get VERY hot, but being on a manifold that constantly flows cold air, heat shouldnt be an issue

My car is a euro model so originally with a mikuni carb, the stud spacing was exactly like in the 3K so no stud adapter was needed.

Your carb has already the notches so you dont even need to make them in your spacer.

Had to build a bracket for the different position of the throttle cable and for the choke cable as the mikuni carb is auto choke.

Car started at first try with the 3K but felt lest responsive and fuel consumption was high, guess some rejetting was due, but as i overhauled in the meantime the original mikuni, that went back in. This how the mikuni looks like, its amazingly well engineered, but dotn thinkl youll find it in the usa


View attachment 120886

So basically CM makes the notches because their carbs have none? So some carbs need them and some don't?

 

8V euro carbed manifold

 

my 3K carb, had no vaccum ports, used the ones already in manifold

 

all of them need them. so its safety measure in case carb doesnt have them like in mine

 

OK, it's a little clearer now I think and I guess I'll just go for it soon.

 

Good luck man, It should work now that we see how it is, I really hope it does, keep us updated

 

your carb certainly has two notches in the mating face...

 

You heed the vacuum to get to the ports on the carb base, the 26 to 28 taper is required to give good idle and to stop flat spots just off idle. If you don't mind a bit if a stumble then a 28 hole should work, but I can't guarantee it will be nice to drive.

If a 28 hole would have done the trick then the adapter plate would have it instead of the tapered hole.

 

GV, it doesn't happen often, but totally disagree with you here....

 

Thats fine. If you have had one work on straight hole adapters then kudos to you.