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84 prelude carbs

I have a 84 honda prelude that has been sitting for years. Some repairs were made to get fuel to the engine. I now have fuel to the carbs but it doesnt seem to be going through them. Im thinking the carbs need to be cleaned. What is the easiest way to do this on this vehicle without being able to start it?

On the vehicle? I dunno. The needle valve operated by the float is probably gummed up, the float mechanism itself is probably gummed up, and the orafice into the venturi is probably gummed up. I suppose if yuo could force some solvent through the system it MIGHT help. But I think you’re looking at an off-the-engine rebuild. Besides, I wonder how the rubber in your accelerator pump is doing?

Man! I’m glad I’m not you.

These carbs are very complicated. And if you’ve never taken apart or reassembled one of these, find someone with gray hair that works on vehicles. And mention that you have a problem with your Honda carb. And watch them run into a corner and pee all over themselves.

Tester

If I wanted the easy route I would try to get it running with starter fluid and sea foam in the gas tank, once it runs start with the inside of the carb hitting whatever you can(carb cleaner), then let the sea foam do its magic.

I have been a tech for years. Pretty much what i am doing here is hoping someone with honda experience will have a brilliant idea that doesnt involve taking the carbs off or rebuilding them. It looks like a nightmare. Ill try the sea foam idea and hope for the best!!!

I had an '82 Prelude back in the day. These CVCC carbs are incredibly complex and very expensive to rebuild. I don’t think the seafoam will help. If gas is not going through, an off-the-car rebuild is needed. When I had issues with my carb, like leaking fuel and rotten gaskets and seals, I was advised to use a Weber 2-bbl progressive kit and dump that carb. I managed to keep that car for almost 7 years after that.

The carburetors look like Rube Goldberg/Skinner Union cross breeds. I would second B-K and suggest you search for that Weber and an adapter.

I agree with Tester…They didn’t work very well in 1984 and they CERTAINLY haven’t improved with age…If emissions testing is not part of this picture, then using some sort of aftermarket conversion carburetor is the way to go…Sometimes, it’s just better to walk away…I bet there is some sort of TBI injection kit that would fit this car…

You can make this run with a Redline Weber kit, but this is a CVCC engine and going with the Weber turns it into an ordinary engine. But a brand new Redline kit is probably cheaper than rebuilding that three barrel you have now. Plus with the Redline kit, you can get rid of that maze of vacuum tubing.

If needle valves are stuck, you won’t have trouble unsticking them. You can remove the top of the carb easily with it on the engine. If you have plastic floats, replace them because they leak and take on fuel. You can reuse them if they aren’t full of fuel but get the replacement copper floats. Have fun.

Go to 3geez.com. It’s a site where owners and tuners of older Honda cars post. They have a separate section for the Prelude. I know that I read a post by someone who got rid of the original car set-up on an older Accord and installed a Weber set-up, and it details the switch step by step. If it were up to me I would follow the advice offered by Keith and look into a new Weber carb. The problems related to the carbs and vacuum hoses of the mid 80s Honda cars are difficult to diagnose and repair. Rocketman

The real question is this: Is the car worth what it is going to cost to get it running? If a “Tuner” thinks that body-style is cool, you may be able to sell it as a parts car. Otherwise, should you continue on your quest, it will become a Money Pit…

If it’s the 1.8l engine you can still buy a rebuild kit and float from rockauto.com. Might be worth a try before putting a Weber on it. But you’ll need some (not many) tools, patience, take lots of pics, and some luck getting it all back together correctly…

Also, you need one of these:

or:

84? I don’t think any 84 car had simple carbs. That’s about time the switch was being made to FI systems. My 84 caprice had a simple fuel enrichment solenoid for the 4bbl and it ran pretty good.

Here’s a vacuum hose diagram for one:

And what it looks like under the hood AFTER the owner ‘removed a bunch of vacuum hoses’:

My only workable solution to Honda’s spaghetti soup was to remove the carburetor/s with the manifold and bring all the vacuum control boxes and most of the mechanisms attached to the mass of vacuum hoses out as a mass. The engine with twin side draft carburetors was not CVCC, which used the 3 bbl carburetor. Yes, the 80s engines were a nightmare of plumbing that put many shade tree mechanics out to pasture.

NOBODY would work on these '81 to '89 “feedback smog monster” carbs…Shade tree or otherwise…They were considered to be unrepairable…Most manufactures switched to fuel injection as quickly as they could, even though in many cases they had to pay Bosch royalty fees…Honda held out longer than most, got into a major legal battle with Bosch over patent infringement… That whole decade of cars (The Dark Years) went to the scrap yard quickly and have disappeared from the American Highway. There is no collector interest in these cars…