What was this?

[yoloSun]

 

Looks like two holes burned through a material that I'm going to guess was a filter. Was this causing a vacuum leak?

[john510]

I'm not too familiar with that intake manifold but maybe an exhaust heated intake until the motor warms up ? what was attached to it ? 

[vicdat]

Looks like a clogged EGR...

 

Vicdat

[67_1600]

35 minutes ago, john510 said:

I'm not too familiar with that intake manifold but maybe an exhaust heated intake until the motor warms up ? what was attached to it ? 

 

That's exactly what it is - exhaust runs through it to heat the manifold. Inside is just carbon built up, not any type of filter. As far as a vacuum leak, it shouldn't be an issue as I don't think the exhaust gasses do anything but circulate around but don't actually enter the intake system.

 

[yoloSun]

3 hours ago, 67_1600 said:

As far as a vacuum leak, it shouldn't be an issue as I don't think the exhaust gasses do anything but circulate around but don't actually enter the intake system.

 

Those holes are going directly into the intake - soooo... the exhaust gasses are indeed entering the intake system. I think its part of the EGR system.

If you look at the first picture, you can see all the way through the plenum to where it connects to the intake valves.

4 hours ago, john510 said:

I'm not too familiar with that intake manifold but maybe an exhaust heated intake until the motor warms up ? what was attached to it ? 

I believe I read that the 78-79 l20b was the only intake that didn't use the exhaust to heat the intake; this intake has a coolent line for that purpose...I think.

 

I don't think that was carbon...two inches of carbon...thats crazy. 

Ill check again.

I'll post what was connected to it tomorrow so you guys can see.

[vicdat]

My '79 King Cab had about 2" of crusty carbon built-up in that area once from the EGR....clean it out real good and use the correct gasket. Check the valve itself cause the will clog jamb it up to stay open (or closed). Here in CA if its older than 1975 you can shitcan all that old emissions stuff. Especially ditch the smog pump if you have one.

[yoloSun]

Ok, I got the correct gasket.

upload pic

[vicdat]

Is that a homemade gasket???

I think the factory is metal and fiber impregnated...

Either way it good for 10 HP hahahah

 

Vicdat 610

[yoloSun]

lol, ya it's a soup can lid.

And I did ditch the smog pump and the rest.

Except for the gas fumes canister gadget, but I forgot where the vacuum lines go. 

 

 

[vicdat]

I think if your shitcanning the pump, than do the same to the entire EGR and put a slightly thicker plate over the opening to seal it off for eternity....

[yoloSun]

7 minutes ago, vicdat said:

I think if your shitcanning the pump, than do the same to the entire EGR and put a slightly thicker plate over the opening to seal it off for eternity....

 

Ya that's the plan, I wanted to go thicker, this will be a temp template. I can't cut fancy, so it'll have to be a square cut piece of steel.

[vicdat]

Good man...keep on truckin'!!

[Crashtd420]

2 hours ago, yoloSun said:

 

Ya that's the plan, I wanted to go thicker, this will be a temp template. I can't cut fancy, so it'll have to be a square cut piece of steel.

You dont need fancy tools to make it look good.... cut it more like a trapezoid then a square then just use a die grinder with the flap wheel on it to get the shape closer to what it should be.... 

If you have a bench grinder even easier.... 

[datzenmike]

 

This is for the EGR exhaust gas recirculation manifold to bolt to the intake. You have a '79 engine and it's intake is warmed and cooled by coolant flow through the runners. You'll find a small pipe for this on the front right base of the carburetor, on the intake.

 

The easiest thing to do is assemble this with a new gasket and pull the hose off the EGR to disable the EGR. I highly recommend at least keeping the EGR manifold that bolts on here even if you remove and seal off the EGR valve. This will keep the PCV valve operating. If you make a cover plate for here be sure to drill and tap a hole to mount the PCV valve to it.

 

 

Here's a '79 truck intake I modified...

 

 

I ground away the three studs and re-shaped it, sealed the holes with J B weld. Tapped one hole for the PCV valve and a vacuum port. Looks somewhat like the early L16 intake but it's a '79. You can see the coolant outlet pipe/hose for the warmed/cooled intake.

[yoloSun]

And...does the coolent flow anywhere near where you tapped that PCV valve?