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  #21  
Old 09-17-2021, 09:33 PM
RedArrow RedArrow is offline
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Default EGR delete--- pictures

Very pitted actually. and this picture was taken after i sanded off a lot

That crack looks thick in macro pictures but not so bad in real life.

I need a better plate.
Lets see if this holds..
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Last edited by RedArrow; 09-17-2021 at 09:42 PM.
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  #22  
Old 09-18-2021, 05:36 PM
RedArrow RedArrow is offline
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Default Update on the day after

I did a test drive today.

There`s a big difference.

Now the car pulls much harder (=stronger), starting from standstill in 1st gear and in every higher gear too, it `has more juice`/ it`s significantly peppier (5th/Overdrive not tried yet).
It gets to certain speeds way better, the power curve is better; engine has a feel to it like it runs more even now. As a result of all of this, the wagon gains speed easier, gradually and smoothly.
I heard it sounding better too when the turbo joins in.

I didn`t go on the freeway yet but already I `m convinced now that its driveability improved by a lot.
A substantial change also in how well different RPM ranges harmonize with what I`m doing with the shifter and acceleration.
By the way, the exhaust cement paste dried/cured into a really hard substance. A `bad` choice of a paste, maybe, but if this fails I will use JBWeld Extreme heat paste.


I`m glad I tackled this EGR `blow-out leak` issue. Car is happier, driver is happier. Ngoma, kuddos for the quick motivation and for uploading your EGR-delete thread for this good community of diesel brickers (and for VW owners, of course ). Thank you

PS. I`ll have more bolts to check for tightness because the intake manifold also got removed when the exhaust manifold was taken off, my intake also received a new gasket back then. Some of those bolts are also hard to access so I`ll see if I missed some torque specs on the ones I had to do `by feel`.

Last edited by RedArrow; 09-18-2021 at 05:59 PM.
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  #23  
Old 09-18-2021, 05:51 PM
ngoma ngoma is offline
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Default

Quote:
Originally Posted by RedArrow View Post
The double layer metal gasket was found in fully reusable condition but in the end I decided to use no gasket at all. This may be a mistake, I`ll hear your opinion about it.
Aluminum plate on cast iron manifold would seem to need a gasket, no? Thinking they have quite different rates of thermal expansion.

Quote:
Originally Posted by RedArrow View Post
Do you think the exhaust cement can cause problems IF tiny particles end up going in/falling in?
Well...... just imagine them hitting the turbine impeller!

Quote:
Originally Posted by RedArrow View Post
DID YOU USE ANY GASKETS IN YOUR FIX (at the manifold)??
Yes, as previously stated I did reuse the gaskets. They were worn but intact. Some kind of meshlike material? I'll see if I can get a photo of it.

Quote:
Originally Posted by RedArrow View Post
About the crack.
I have this crack on the very bottom of the exhaust manifold where the two sides meet, right in the exact center (lower lip).
Didn't see any crack in your photos.

Quote:
Originally Posted by RedArrow View Post
Are these manifolds easily to weld?
Nope, cast iron manifolds, especially old well-used ones, are notoriously hard to weld successfully. But maybe you know an old-timer with a proven track record?
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  #24  
Old 09-18-2021, 06:18 PM
RedArrow RedArrow is offline
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Default Redo

Thanks again for joining the egr talk...

Yeah I thought these `antique` manifolds would be challenging to weld, ugh.
The crack is at the very center of the lower lip, kind of vertical and symmetrical. One of my pics I think shows it. I`ll check again..


Oh yeah, the turbine wont handle it well because this cement looked like it solidified into a hard material. I should get the plate off, clean it well and NOT USE THE PASTE where the plate meets the hole, only around the hole and on the plate between the stud holes.



I misundestood your post about the reuse of the gasket bc I actually couldnt see a gasket in your photo (at the lower egr spot, not the intake one) I`ll look at it better. I read they were in good cond but I still didn`t think you actually put any in. OK

Was your mesh-like gasket a metal mesh gasket? Interesting. I`d like to see it if picture found or get a link because I think my 2-layer stainless steel gasket itself was not flat enough to not be interfering with the desired flatness of the mating surfaces. I didnt use any gasket unfortunately.


So... the plate will come off and I`ll JBWeld it back on, using better looking (&safer) copper nuts and much less paste. And a gasket, if a nice flat looking & heat tolerant one shows up in my search. I should also chop off most of the stud as it looks really ugly sticking out a lot (nope!! bc then it gets harder to fish it out one day) UGH


I appreciate the input... useful advice, as always.

Last edited by RedArrow; 09-18-2021 at 06:38 PM.
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  #25  
Old 09-19-2021, 10:37 AM
ngoma ngoma is offline
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Very hard to sufficiently clean the CI from the ingrained carbon after years of use. And the CI often cracks afterwards adjacent to the weld.

Usually when applying sealant to a flanged area it is best to just spread a small bead along the center of the surface and around the bolt holes. Have you ever pulled chunks of silicone caulk off of a partially blocked oil pickup screen? Where do you think that came from?* Less is more!

*(Hint) Overzealous oilpan gasket or valvecover gasket replacement maybe?

Gasket

Here's one I didn't reuse, its a multilayer steel (at least two layers). Looking at the surface of it, it may have had an additional screenlike layer, not sure.

P1040279.JPG

P1040280.JPG

EDIT, LATER...

Now I'm thinking you should just do something like this:

How To Make Custom Exhaust Gaskets For Your Special Project
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  #26  
Old 09-19-2021, 07:33 PM
RedArrow RedArrow is offline
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Default `Less is more` means a redo of the egr project.

That gasket making process looks easily doable and that material looks like something that would hold well. I will need to study the entire page bc for now I only had time to look at the main pictures.


That gasket of yours, looks like one of the ones that my car had in there. Another one was also kept in similar condition from a car with 182k. Probably that was its factory gasket... I still have it, will inspect it later.

About the CI manifold...
occassional extensive torching (some every 8-10yrs??) and banging studs or even repairs involving removing of manifolds or turbo could have resulted the exh manifold getting that hairline crack...
I thought it was me who caused it to crack, because i did torch it quite a lot... even painted it a few times so it got moved around a lot and knocked it a little when placed it on bench or in the wise for sanding.... I only blamed myself for it until I found out that my spare manifold also has it, at same spot.

With my kind of luck I think a third one would have it too, in case I bought one

I have four different kind of gaskets for the area and i`ll take a picture of each. Matter of finding them now...
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