garyhgaryh

I think the '93 and earlier preludes have a welded egr cleaning port like this:



My '93 Civic VX also has a welded port. Has anyone attempted to clean the ports by drilling through the weld?

Thanks,
Gary

M@

I'm going to start on my 95 tonight hopefully. Hopefully I'll remember to take pics.

garyhgaryh

Ok, let me know how it goes.
I just took out my egr valve. I put vacuum on the EGR port and the plunger does not move... A new valve is about $170 from Honda .

Gary

vinuneuro

How do you know? The valve isn't always active. Afaik, it's only operational at part-throttle under load.

M2B4

mine was like that i just drilled through it, but matt said if u shave that glob down there plugs under that. give that a shot

M@

Well I got the, thing off and clean enough to start grinding.

Maybe my technique was flawed, but it took 3 hrs to get the intake out.

I took my egr valve off a few years ago, and cleaned to carbon off the valve, and that got it moving again. I used the ol' mouth vacume to test it move

for B12 chemtool, and simple green. I basically just sprayed that stuff on and out ran all the carbon in the intake runners. Sprayed it in the EGR valve port and got one of the runner ports to open up.

Tomorrow I'll be drilling into the globs to see whats below there. Has anyone measured the diameter of the access ports on top of the runners? I'm wondering what tap I should get for the hole. If I can just buy two that would be great.

garyhgaryh

All I did today was take the EGR valve out. Funny thing is that I put vacuum on the port, but the plunger didn't move. On my old celica, it will move when there is vacuum. Isn't that the way it works on the civic EGR valve? I assume it doesn't need any signal from those wires.

If that's the case, I think my EGR valve is bad. Need to get another one. I still need to drill or grind down the welds. I am thinking of just drilling hold straight in (not all the way)... Clean the port and then threading it to put a plug in there.
Gary

M@

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by M@ &raquo;</TD></TR><TR><TD CLASS="quote">
I took my egr valve off a few years ago, and cleaned to carbon off the valve, and that got it moving again. I used the ol' mouth vacume to test it move

for B12 chemtool, and simple green. I basically just sprayed that stuff on and out ran all the carbon in the intake runners. Sprayed it in the EGR valve port and got one of the runner ports to open up.

</TD></TR></TABLE>

garyhgaryh

Today I met someone who had EGR valves for sale. He had two. I put pressure on the vacuum ports of both the EGR valves the guy was trying to sell me and none of them caused the plunger to move. I told him that's how mine reacts to vacuum so I ended up not buying it since I figured my EGR valve is not bad. We reved my engine and we felt the plunger on my EGR valve go up and down when the engine was reving so it appears that the electrical lines to the EGR valve has something to do with whether or not the plunger moves.

I ended up buying a VX intake from the guy. I'm trying to decide whether to drill through the welds and find out what's under there and clean the ports and plug it _OR_ take a high pressure wash wand and aim it at the egr ports hoping it will clean up the carbon with high water pressure, then swap my intake for this one and hope I pass smog.

Gary

mgags7

The egr solenoid has a vac tank that "amplifies" the vacuum pressure to get the valve to open.

If yours is too clogged up, pushing it manually open will not work. Just get a bunch of brake clean on the needle valve section, it always gets clogged.

The plugs are really in the those ports, then honda welds over the top of them, if you grind them down flush you will see the outline of the plug, at that point you can tap/slide hammer them out and that will work, though I just drilled through them with the full size bit and that worked fine.

M@

Start w/ water if you have the mani off anyways. You should be able to get atleast one of the ports open. You also might be able to take an allen wrench and poke up from the runner to loosen the carbon up, and blast again. With out drilling I don't think you'll be able to get it super clean.

When I drilled mine out I didn't seen any brass. If you are just going to jb weld them you might as well just take a 1/4" drill bit down throught the center of the hole. Notice the angle of the casting and follow it. Grinding will only remove material that you can use later to help seal the hole.

The vac that opens the valve isn't any more powerfull then you can apply with your mouth. Then again maybe I suck.

garyhgaryh

I'm not sure if that is quite accurate. If I put 8 in of vacuum, the plunger should move.
I put 20 in and it still did not move so I amplified it by 2.5x and still no go.

I also am not sure if there is a brass plug under the welds as no one else has mentioned it when they drilled through it.

Gary

garyhgaryh

I'm not going to remove any material. I'm going to drill through it and thread it after cleaning. Does anyone know where to buy threaded plugs? I think I've seen them at home depot.

Gary

M@

I was going to use some allen set screws, but they didn't fit real tight, and I was afraid that they might get sucked into the EGR passage, and then I would never get it out. I would suggest using a bolt, but if you must Ace Hardware has plenty of different set screws to choose from.

My mani had no brass under the welds. The material could have been 1/2" thick from the top of the weld to the EGR passage.

garyhgaryh

Set screws might work! I have an M12 tap so I'm going to look for a threaded plug with M12x1.25 specs.
Gary

mgags7

I doubt set screws would come loose under any circumstance as long as they were installed correctly and some threadlocker was used.

You definitely had the plugs in there though, they all do, you can't just meld aluminum in there like that to cover the holes and expect it to suspend itself without a plug underneath to hold it up.

You would never have noticed the plug unless you drilled at the exact right size to just leave a small portion of the side in there, or you ground the extra metal off. Like I said, if you do that, when you're done you just hammer the plug in then jb weld over the open hole.

M@

Speak for yourself. There was no brass in my intake. I think I would have seen even a sliver of brass in the shavings. Not to mention I ground down one very far before I decided I didn't want to grind all the way into the passage.

It shouldn't be all that hard to weld w/o a backer especially if you have a machine that will do it all for you.

It doesn't really matter either way though. Just drill and tap, you should be set then + you have more material for threads.

garyhgaryh

Hey mgags,
I agree with you on the set screws with threadlocker, but...

I'm wondering where you got the info you're giving us about the brass plugs underneath the welds. Are you assuming there should be a plug there or that you actually ground down the weld and found the plugs or outline of the plugs? It's ok to take a very well educated guess, but what I wanted to know is if you actually saw the plugs?
Thanks,
Gary

M@

I don't really see how it matters if mgags has brass or not. It sounds like yours could be either way, and the only way of knowing is to drilling into it.

Suit yourself on the set screws. I'll even send you some 5/16" 18 thread/in 1/2" long allen head stainless set screws. There's no promise that they won't fall in.

mgags7

Guys read my post again, yes there were plugs in all my holes.

There has to be, you literally <u>can not</u> just weld aluminum into an open hole like that and expect it to not drip into the egr passage. The plugs are put there to hold the molten aluminum from dripping down inside. I guess honda thought that welding over the top was necessary to stop leaks, but a well installed plug woud definitely do the trick. oh well.

I'll dig through my trash and show you the peices of metal plug that I drilled out if you like....

garyhgaryh

mgags: it's cool. I was just curious, that is all. What you says makes sense.

M@: yeah, I'll take 'em if you don't want 'em.

Gary

M@

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mgags7 &raquo;</TD></TR><TR><TD CLASS="quote">Guys read my post again, yes there were plugs in all my holes.

There has to be, you literally <u>can not</u> just weld aluminum into an open hole like that and expect it to not drip into the egr passage. The plugs are put there to hold the molten aluminum from dripping down inside. I guess honda thought that welding over the top was necessary to stop leaks, but a well installed plug woud definitely do the trick. oh well.

I'll dig through my trash and show you the peices of metal plug that I drilled out if you like....</TD></TR></TABLE>

What if the mani was upside down? Would it drip in that way? There were no plugs in my mani, maybe you think that welding transformed the brass to al, that may explain why it wasn't in my mani, but to be honest I'm done. I don't really care if you had brass or not.

Gary if you want the plugs send me an im w/ your contact details. If you already have a tap then it would be cheaper to use that and go buy plugs, then use my plugs, and go buy a tap. I was sorta kidding, they are only $0.50 a piece.

mgags7

If it was upside down, it would have dripped out, and the melting point of aluminum is by far lower than brass, so that scenario wouldn't have happened either. This is a dumb argument, I was only trying to show that the correct way to do this job in order to hammer in new plugs and have it seal right is to grind the aluminum off so you get flush with the top of the manifold, then drill a small hole and thread/slide hammer the plugs out. Sorry to make such a stink I just wanted to clarify that for the people who insist on doing everything to honda spec.

garyhgaryh

hey m@, I have taps galore down here, but don't worry about the plugs..
Too much trouble.

Thanks anyways,

Gary

hondaequikppd1

hey man sup..yah im bout to do my cleaning soon and ive ordered the plugs..couldnt find an article bout our welded over plugs, till i found this thread, anyways..how did it go? i got a 4th gen u.s. h22a1..