Engine Coolant leak from throttle body

[91GTstroked]

Hey everyone!

So here's the deal. I replaced the bbk 70mm TB and EGR spacer and went back to the stock TB and EGR spacer. I bought them off eBay.

I thought I cleaned them up well and used fel pro replacement gaskets.

It's leaking through the TB gasket. I can see a little puddle in the TB as well.

The car is a 90 7 up edition vert and motor is stock. So I don't really want to bypass the coolant passages on the EGR.

I've never had this problem with any other fox mustang that I've owned. People replace Throttle bodies all the time and I never hear about this.

Anyway, I ordered another set of gaskets . Can I use a light coating of "right stuff" rtv on the TB gasket that mates to EGR side?

I hope to work on this on Thursday.

Thanks!

 

[General karthief]

Yes. I use the blue Permatex on both gaskets on the EGR spacer side on used stuff. I also make sure both surfaces are flat.

 

[91GTstroked]

Yes. I use the blue Permatex on both gaskets on the EGR spacer side on used stuff. I also make sure both surfaces are flat.

So to clarify, you also use it on the EGR to plenum gasket, but only on the EGR side? Basically, can I just put some on the mating surface on both sides of the EGR spacer, then put on gaskets?

I have some blue permatex thermostat housing rtv but I've never used it before.

 

[General karthief]

Yeah, I smear a thin coat on the gasket, stick it on and let it set for a few minutes with some weight to keep it pressed on, then do the other side of the spacer.
Inspect the spacer good for pits and cracks.
Normally I would say to block off or remove the lines to the spacer but it's kinda needed to cool the EGR gases entering the intake since this has a functioning emissions system (right?), I know you think 'cooling' with 190* liquid don't compute but the exhaust gases can be a few hundred degrees.
Disclaimer: info not based on any real mechanical training, use at your own risk!
Not many people or animals were harmed gathering this experience.

 

[AeroCoupe]

find a flat surface, get some 800 or 1000 grit sandpaper and check how flat the TB and spacers surfaces are. Don't mash them down or anything but with light pressure drag the TB and spacer across the sandpaper that is on the flat surface (glass works very nice) and see what king of pattern you get. Should have even contact across the entire surface.

 

[91GTstroked]

Update:

I just completed doing it over today. The EGR spacer definitely has a fair amount of pitting on the TB side. So I used permatex thermostat housing rtv on both gaskets that mate to the EGR sides. It's colder here right now, so I'm going to wait a few days before I start it up.

 

[91GTstroked]

Update:

Okay guys, it's still leaking. I've barely driven this car since going back to the stock setup.

I'm guessing the mating surface isn't straight. What are my options?

Can I try rtv only on both EGR sides? And what kind? My last attempt was gaskets with permatex grey thermostat housing rtv.

Or can I bypass the EGR coolant lines if I'm still running the EGR setup? Car is mostly stock.

 

[slow84lx]

That sucks!

Re-read post #5. Following this process can take care of the pitting and get the surfaces flat.

When it is apart check closely for cracks.