Hi Phillip ,
Have you addressed or further evaluated the vertical crack in your 2 stand alone ( non-OEM-toyota ) spacers set up under the cast iron carb. base / above the aluminum intake manifold ?
Visually to me these look like some sort of aluminum shop-made or home-brew type of
spacer blocks set up that someone 1st made 1 of them , then realized that the height difference between the carburetor airhorn and the air cleaner, metal housing that goes over the stud out of the top of your carburetor was not was not tall enough to meet as in the carburetor wasn’t high enough so they created a second spacer and stacked it on top of the first one to achieve the right height for the airhorn of the carbureted and they look aluminum as in metal in nature, but they could’ve been it could be painted of some sort of of course, silver too ?
I would simply say this the way they are fixed in place with some sort of like semi translucent generic Permax sealant and not like any type of like fiber gasket material media, as well as the fact that there looks like there’s some sort of crack in the vertically on the top one, the permatex type sealer and the visual crack that’s a smoking gun of like major vacuum leaks That’s a starting point here because you’re not going to get any type of results that are notable or positively benefit you from a like a you know you you complete the step to do the De-smog and then you you evaluate your benefit factor make sure it’s hooked up right then you go into the next step-by-step as you’re trying to do with a D- smog, but having this this this main area of vacuum leak it’s an Achilles heel because its currently setting you up for failure as is …
You can take the currently available non-USA 2F engine carburetor insulator heat shield and you could install it on your engine on your intake manifold in place of that set up. That’s on there now in the case of your 1975 2F you will have to take a metal type holesaw as in like a hacksaw blade fine tooth and you’ll have to notate the location. There’s there’s a few ports like vacuum fitting ports. The model 2F insulator does not these needed knockout holes.
So this is very simple you would measure five times and simply cut once making like a a paper template out of like tracing paper the stuff you could see through translation you could buy at Michael’s crafts or like JoAnn fabrics, for example and you see through it and you would like center it over your carburetor studs for example that’s easy enough to punch holes in it and then you simply take lead pencil and you would make your necessary knockout circles. Then you lay it over your insulator and you mark it with him you know like a white type of sharpie white paint pen what’s important is You must always remember. You need to run the drill with the fine tooth holesaw in reverse like backwards you can get away with one with jagged teeth like for Wood, but it’s better to use the one that’s for metal. If you have one for ceramic tile they work well too. You don’t have to because they have a diamond aggregate. You could run those in either direction but remember slow and steady is the key here and you start on one side, get it going and get the groove and curve and then flip it over and do it from the backside this way when it comes through the the heatshield material is sort of like a fireproof Kevlar type fiberglass if you will it’s kind of like a on boat engine, so you do it from the whole saw from both sides similar to wooded carpentry And that way then the heatshield clear all that the heat shield is bolted and secure down with 3M8 bolts they’re short ones M 8 x 1.25 and then they have to be like the distributor bolt. They have to be real short like no taller than 16 mm you’ll be able to use chew out of those three but I think for certain you either have to drill an extra hole to catch the third one you have or you simply don’t have the third one and the insulator wings the material that has the shielding on it the silver stuff on the bottom NASA space capsule reflector stuff they kind of float there’s nothing pushing on it so they could freely float in all reality they could get away with not being bolted down. You still have the centerpoint of the four carb studs. The insulator comes pre-factory install installed with gaskets on both sides or like their tan. I call this OEM Toyota gasket media

CAMEL-FLAUGE
Once you’ve installed a factory, Twitter lead model 2F engine space/heat shield set up. I don’t think you’re gonna be completely out of the woods yet I think for certain based on what I see in your tech pictures your carburetor airhorn is still gonna be too short to meet up with the oval air cleaner. It’s just a gap so I would only find the link, but there’s a vendor that sells a I would call it simply a very, very well thought out custom part. It’s not a reproduction part. It’s a ring. It’s an adapter for this exact situation. It’s scenario that you have, and it just simply presses onto the lip of the top of the airhorn in the carburetor and then you use the OEM Toyota. O- ring on the top of it to made it to the bottom of the air cleaner housing itself, where the stud is your carb stud should be long enough to be still utilized here as well
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