Cleaning EGR passages in intake, EA81

[Frank B]

Can someone describe the EGR passage in the intake manifold? I had to remove the EGR valve to clean it, it was completely clogged with carbon. I managed to get the valve clean, the pipe, and the pipe port in the intake, but after digging out the intake port I can't tell if it turns left, right, or down??

89 EA81 carb

[Frank B]

I think I found my answer. In the haynes manual, page 135 figure 6.1 shows the passage splitting to each side of the engine. About halfway between the carb and head there are orifices into the intake runners. The left side is 10mm the right is 13mm. It looks like the side with the air suction valve is the smaller one.

Now, how in the heck would you clean those passages? The only things I can think of is removing, and stripping the intake to either soak it in a tub of solvent, gas, kerosene, paint thinner, or just blasting the passages with a torch to burn out the carbon.

I thought of just drilling a hole straight under the carb so it dumps out there. I don't know. I plan on swapping the intake with an EA82 intake when I ever install my weber so I may just leave it alone. The problem is that under load(uphill) or heavy acceleration over 3000 rpm, I get a ton of detonation and some smoke out the pipe?

[TomRhere]

I took a look at a manifold I have in the garage. Yeah, it splits to both sides, left side just above the temp sensor, right side just above PCV valve. There are plugs there where the passges turn into the runners, but it don't look to easy to get them out. Somewhat of a slight attempt at putting a slot for a straight blade screwdriver, but it looks way iffy on the possibility of turning them out.

[Frank B]

Yea I saw the plugs. I read online that a piece of speedo, clutch or other cable on a drill can dig out the passages. Yesterday after I cleaned what I could I also performed a quick fix on a radiator leak(JB Weld) so I couldn't run it. Today, after the JB set up, I ran the engine up to temp and opened the EGR manually and the engine fluttered. So it now works.. , and I really don't NEED to clean those little passages since they're obviously open. I may pull the egr back off, then spray some serious carb cleaner in it as the engine runs to pull the cleaner in. Maybe that's the trick.