AKA "air vent cut off diaphragm"
This little guy keeps a valve closed when vacuum is supplied or held to it (engine running). When the engine is shut off the valve opens and fuel vapors are directed into a charcoal canister, rather than vented into the atmosphere.

When the diaphragm is perforated like mine is, and engine vacuum declines (when you hit the go pedal) the valve opens and creates a huge air leak. So no go with the go pedal.

I found the description of how this system operates (when working properly) in the emissions section of my service manual

and figured it out from there.

Unfortunately I cannot find a new diaphragm. Honda has discontinued this part, it's not in the rebuild kit for the carb, and I can't find it in the aftermarket anywhere.

So my choices are to either paste up the rubber with some sort of bonding agent and hope it works, or eliminate this part of the emissions system (all emissions systems must be in place and APPEAR to work)

So for now I'm using a less perforated diaphragm scrounged from another carb and MrHanky drives a whole lot better.

Posted by Scott Korb at 11:41 PM | Permalink

More power AND better gas mileage? Sign me up!
Less complicated? Better still!

BUT it wont pass NC state inspection.

Vehicles in NC under 35yrs old, but built before 1996 must pass a safety inspection including a visual inspection of emission equipment. All emission equipment must be installed and appear to work.

I installed a WEBER carburetor on my 1982 Civic. It has one electrical wire for the choke (optional), one ported vacuum line for the distributor, and one manifold vacuum line for the power brakes (optional).

Damn if I cant get through an inspection. Actually, I can, but I need this car to be user friendly.

So I had to put this monstrosity back on it:

Continue reading "unintended consequences" »

Posted by Scott Korb at 11:53 PM | Permalink

I was expecting to find bad things wrong with the little red Civic... specifically a valve in the cylinder head going bad. I checked over all of the ignition parts, including using an oscilloscope to find this misfire -nothing. I did a compression test and a leak down test on the engine, and I found nothing wrong there either. I checked over the PCV system since it runs through the #3 cylinder... nothing.
I sprayed carb cleaner over every intake part with the engine running, listening for a vacuum leak... nothing.

Luckily I have access to other expensive diagnostic tools, like this: (pic after jump)

Continue reading "Hooray, I'm wrong again!" »

Posted by Scott Korb at 6:28 PM | Permalink | Comments (1)

Dreya and i have decided on a name for trying to sell our creations.... and we made several things last weekend. Check out our Flickr account at

http://www.flickr.com/photos/23026128@N06

(cut and paste if necessary)

In other news, Sean bought some steering parts for the Lincoln. We'll be installing those shortly. He's putting some shift solenoids in Vic's Volvo, so we'll see if that pans out, or if it needs a trans.
Mr. Hankey is running fine for Dreya but is a little drafty in the cold. The Camry still needs a Cat. Sean's been driving her to work and she does fine... but she needs a tiny bit of body work and the P. side fender replaced due to a little trailer accident.
I've been driving the CRX since towing it home from Maryland after Christmas. It burnt the power wire going to the new "autozone" fuel pump. Fuses were all fine. And it's been doing fine since fixing the wire. No more long trips until i put in a Honda pump and a fused wire there though. I'm going to do some other work to it too. I fixed the flat tire which I'm sure would have blown out at 80mph had the fuel-pump not quit. Good car.

At my job, among other things, I have to replace a heater core in a '98 Lincoln Town Car. This is not fun. I might take a picture of the interior minus entire dashboard once i get it out. I'm still working on removing the steering column w/o compromising the airbag system. Old plastic is difficult to deal with. Maybe next week or so... or not.

Posted by Scott Korb at 10:46 PM | Permalink