Dumb question.....

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83Burban

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What is this called? Think it's got a vacuum leak looking for a new gasket.
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Choke block off, that's where a manual coil sprung choke would be, to take advantage of the crossover on the intake, but my edlebrock intakes always were completely casted in that void, meaning you wouldn't have a vacuum leak from there, unless I didn't notice I tiny hole, which I don't believe would be there.
 
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Southcoast85

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the only dumb question is the one you didn't ask.
 

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Choke Block-Off plate. Get some gasket material from your favorite auto supply store and make your own. Unless they happen to carry a gasket for that.
 

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It is a choke block off plate and I've not seen a gasket for it in any of my catalogs, and I have a lot of them. And @Snoots is right, just get some gasket material, the heat resistant type and make a gasket for it. But that is if you know there's a leak coming from there. How's this, throw some soap on that intake and you might find any number of things that need tending to.

People, keep your engine's clean! You can keep it stock all you want and never touch it, but from time to time clean the engine of oil buildup, dirt, leaves, pine needles, dead bugs, and whatever else. Get a can of "Engine Bright" spray on engine cleaner, let it sit on a cold engine, agitate the heavy buildup areas, then after about fifteen or twenty minutes hose it off with a high pressure nozzle, like a regular water hose nozzle is enough. Take a zip lock bag and put it over the carb, if you want tie it on with a zip tie, don't spray directly on the distributor, and the rest will be okay. But keep it clean and you'll be able to spot those leaks long before you can't even identify what or where something is leaking or where it's leaking.
Yeah, I know I don't have any business telling people what to do, we're all adults. But you know, sometimes people have to be thrown a hint, a reminder from time to time, that's it's past due time to do some general house keeping.
 

Raider L

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When my truck had the two bbl on it, I had that spring choke thing on the engine. And a dang EGR valve to. And the throttle solenoid to! Oh yeah, I forgot, it also had the smog pump on the engine when I bought it. It's funny that drag racers have gone beck to the smog pump to draw pressure off the engine at race rpm, instead of letting it vent overboard. Also it actually builds power by venting the pressure off so completely it allows the engine to build rpm, on the other end of course.
 

83Burban

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@Raider L

I just saw yours and extremes posts on this. But thanks for the info.

It sounds like I have a massive vacuum leak coming from somewhere around the carb. But I cant find it... Ive tried spritzing carb cleaner / starting fluid around but nothing impacts it.

Is a 750cfm carb just that loud? Im pulling a steady 18lbs on the vacuum guage.
 

AyWoSch Motors

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Thought that was an old EGR block off plate.
 

Raider L

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@83Burban,

It just came to me. Do you have the customary Q-jet? If so look very closely for leaks at hoses connected to the carb, like PCV hose, any small hoses for timing, or whatever Q's have going to them. Does the engine run rough or have a stumble taking off, or anything like that? Gas mileage gone away some? Look for cracks on hoses. Some may only be under the hose closest to the engine where the heat is, I've seen that. Any other problems with the engine running that might be engine vacuum related?
 

83Burban

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No...i have a newly rebuilt eddy 1407 on a 1" spacer. Ive checked all the gaskets. And the truck seems to be running quite well.

Ive checked the vacuum hoses. Replaced one t-fitting. I'm beginning to think the carb is just loud. Although the sound does not really change if I pull the cleaner off.
 

Bextreme04

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No...i have a newly rebuilt eddy 1407 on a 1" spacer. Ive checked all the gaskets. And the truck seems to be running quite well.

Ive checked the vacuum hoses. Replaced one t-fitting. I'm beginning to think the carb is just loud. Although the sound does not really change if I pull the cleaner off.
Generally speaking, a huge vacuum leak like you describe will cause the engine to run really badly. Have you checked the hard line going into the back of the carburetor for the brake booster, or the fitting going into the intake manifold in between the carb and distributor? You can see if it is just the sound of the carb by cupping your hand over the carb bores and see if the sound dulls out or changes pitch when you do that.
 

83Burban

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Generally speaking, a huge vacuum leak like you describe will cause the engine to run really badly. Have you checked the hard line going into the back of the carburetor for the brake booster, or the fitting going into the intake manifold in between the carb and distributor? You can see if it is just the sound of the carb by cupping your hand over the carb bores and see if the sound dulls out or changes pitch when you do that.

I really don't think its running badly at all. And I have hydraulic brakes so no booster line. I tried to take a video...but....its kinda just loud. I dumped a little fuel right on that fitting between the carb and dist. Nothing changed at all.

I tried cupping my hands over the carb....maybe there was a change. Its hard to tell. Had a few too many guns go off by head to know for sure lol
 

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