MaximRecoil

Black arrow:



My neighbor thought I should perhaps run a hose from it to the place on the [Weber] carburetor that the white arrow is pointing to (it is currently blocked with a rubber plug).

It looks like I'm missing a lot of the original emissions equipment. Should I bother trying to connect the EGR valve (assuming that's what it actually is) or just leave it be?

komh98

Leave it be. Don't need all that crap. I don't have any of mine hooked up. Not broke don't fix it. Michael

83

Yeah it's your egr. Not sure that it should connect to the carb though...
If you have a weber then all your emissions stuff should be plugged off. I'd make sure your egr is plugged off, and mostly make sure the diaphram isn't stuck in the open position. That'll kill your gas mileage. My egr vacuum modulator is messed up so I've got my egr all plugged off until I can afford to fix it. I haven't seen a weber in person so I don't know the whole setup, but I don't think the egr has anything to do with fuel or the carb, it just lets some exaust gas back into the combustion chamber at highway cruising. I'm not completely sure though.

MaximRecoil

I looked at a diagram of a Weber online and it looks like the thing the white arrow is pointing to is for vacuum advance timing (nothing to do with EGR).

How do you check to see if the EGR diaphragm is stuck in the open position?

83

Take the two bolts off where it bolts to the head, and the one or two bolts that attach the metal tube going into it from the intake. You may be able to get it off with that tube still attached to the intake, by loosening the nut (you should see it all & it will make sense) but I feel like I had to take the metal hose off. You'll notice a rubber diaphram in there. It may or may not be totally plugged up with carbon. If you look into the hole (if I remember right) that goes up against the head (when it's installed), you notice a pin in there, and that thing kind of moves the diaphram up & down (along with vacuum). You should be able to get something pointy (but not too sharp) in through the top or bottom and move the diaphram up & down. If you can't, it's stuck. Whether it's stuck open or closed...won't be able to tell till you can move it. Somebody may have more info but I don't know how to tell if it's open or closed without getting it to move. You can spray in carb or brake cleaner, or seafoam it to clean all the carbon, and get it moving back & forth.

If the vacuum isn't hooked up to the valve, and it's stuck closed (or freed up and closed because there's no vacuum) then you're fine if you want it disabled. If it's stuck open though, you'll be getting bad gas mileage and performance. It's only meant to open when you're out cruising on the highway. If you've got some time...search here, Marlin, or Pirate for EGR and you can spend all day reading ways of mostly blocking it off, but also arguments about whether you should have it functioning or not, and how to get it cleaned out & functioning better. Unless you're going to go back to a stock carb, you may as well read about how to just block it off.

DIRT CLOD

I removed my whole egr assembly and plugged it all. I didnt have to take the off the lines. I loosened the compression fittings and removed it, plugged al hoses and openings.

komh98

what I done on my 20R is took it off. Made a plate out of some thin metal and replaced it with the metal. My EGR was stuck open. To test it well is reach inside with your fingers and move the internal parts. You can also squeeze the internal part and hold your finger over the hole where the line conects. Let off the internal part and it should keep a vacume on the hole where the line conects. If it don't it is bad. Michael

MaximRecoil

I think I'll probably replace it with block-off plates too just to be sure.

There are two metal tubes coming out of (or near) the EGR valve; the obvious one on top, and one down below. The one on top doesn't seem to be doing anything; neither sucking in air nor blowing it out; but the one below it is blowing air when the engine is running.


The motor kind of sputters when it is idling. You don't tend to notice it unless you listen at the tailpipe, where you hear intermittent "pfft" sounds intermingled with the steady idling sound. If you disconnect the vacuum advance hose from the distributor, the sputtering goes away, and it idles smoothly.

83

Interesting. Mine does the same thing but I haven't seen if it goes away without the vacuum advance.

As long as your egr is closed, it shouldn't matter if those tubes are open...been too long for me to remember where they hook up to but a vacuum diagram should show you. You are missing (unless 20R's didn't have it) the vacuum modulator. It should sit right up above the egr and one of those tubes probably would have gone to it.

komh98

Your advance might be bad on the distributor. You can suck on it and if it hold it is good, if it hold constant pressure. Also you might check if the advance has pressure on it all the time. I know when I got my truck it did, and I had problems out of it. I took all the EGR crap off my truck just running as Lil as possible to get by. I also caped the Lil part under the intake where the pipe hooks up too. Michael