Coolant Leak: New Damage Found - Disaster!

Hey gearheads,

I believe you know how it feels when you've replaced a head gasket and, after an initially successful test drive (this time, I even correctly adjusted the fuel injection timing thanks to this forum ), you look under the engine and see that new coolant is leaking out in the area of the exhaust manifold/timing belt . That's exactly what happened to me today, and I had already resigned myself to the fact that I would never work on cars again.

Now, let's get to the point:

"Actually, all the possible points on our AUDI 80 TDI 1Z with 270,000 km were sealed. However, when rhythmically pressing the coolant hose, you could hear a hissing sound in the area of the front side of the cylinder head. So, I reluctantly removed the new timing belt again, and there it was: Directly above the stud for the tensioner pulley of the timing belt, there is a kind of bushing or cover made of iron pressed into the cylinder head, and this had a tiny hole in the middle . Well, not so bad, because I got that thing out with a screwdriver and now I hope that Audi can quickly get me such a part ."

It's quite interesting what all can go wrong. Has anyone in our forum ever experienced such a problem? Now we are a little wiser. So, if you change the timing belt, check this bushing (remove the rear timing belt cover), otherwise you might end up replacing the head gasket for nothing (well, the car pulls much better now... so it wasn't really "for free" with this LL). It should last 1,000,000 km .

ice cover?

frost plugs!?

Unfortunately, I don't have a 1Z at my fingertips.

'But with us, these things only broke due to external force, or sometimes slipped off the ratchet handle by accident.'

CU Gremlin.

Gremlin wrote:

ice cap? frost plug!?

Sure, here is the translation of the text from German to English:

"Hi Gremlin,"

Okay... I also don't know how that thing is called . In my case, it was clearly corrosion -> The metal sheet could be easily removed with the screwdriver. It's unbelievable . Do you put that part in with some kind of sealant (was there something underneath)? I've been thinking about using high-strength thread locker.

Hi Christian,

"Hey, how long have you had your TDI? What kind of problems have you experienced with it?"
clutch? do you have a chip implanted?


Hi TDI-Seppl,

tdi-seppl wrote:

Tell me, how long have you had your TDI? What all has been broken or defective so far? clutch? Do you have a chip inside?

Hi TDI-Seppl,

"This is my father's car, and he's owned it since it had 40,000 kilometers on the odometer. So far, I've done all the repairs myself (except for the initial timing belt replacement). Consequently, a head gasket replacement wasn't necessary (as mentioned above). All parts are original except for the injectors, exhaust silencers (including the resonator), and countless ribbed belts plus the tensioner pulley. The car has been driven gently (no chip tuning, etc.), still easily reaches 200 km/h, and has always used 15W-40 HD oil from LiquiMoly, costing around 17 euros. The cylinder walls are also in good condition (no significant scratches or grooves)."

Deleted upon request.

diesel.gustav wrote:

Unfortunately, rusted-through fuel filler caps used to be a common problem. I'm surprised that it happened to your car. Normally, the fuel filler caps have a surface treatment designed to prevent exactly this kind of rusting. Also, antifreeze has a corrosion protection effect.

Hi diesel.gustav,

Perhaps it's actually a good idea to replace the coolant after a certain amount of time (since the original fluid was still in there). The metal plate of the core plug was so thin that you could easily poke a screwdriver through it. What was even worse was that when I removed the ZK (a specific part, likely related to the engine), I saw some of the radiator sealant (which we had used as a temporary fix previously) in that area, but I didn't investigate further. Hopefully, there isn't another core plug on the other side that you can only access with the head removed .

diesel.gustav wrote:

Before inserting, make sure the hole is clean, metallically bright, and not damaged. In case of repair, before insertion, we apply a thin layer of Loctite to both the cap and the hole, although I don't recall the exact type right now. If you are interested, please ask me about it, and I will check at the company on Monday.

Don't stress about it... If I get the part tomorrow, I'll just apply some thread locker to it, tap it in, and that's it – job done.

Hello, I also had a leaking core plug on my Passat 35i a few years ago (with 180,000 km). It was rusted through. After a fast drive on the highway, the coolant alarm went off. Adding water only helped for about 10 minutes, then it disappeared again.

There was a hole in the seal, almost the size of a pencil. And the adjacent core plug was also visibly leaking! So I replaced it.

Those were core hole closures in the block.

KombiBlue wrote:

Those were core hole closures on the block.

Oh jeez , this thing is definitely really cheap: 35 cents .

The price is good, that's true. If only the installation and removal were also so "cheap"!

It was a real pain (3 hours for just 2 lids!).

KombiBlue wrote:

It was a real pain (3 hours for just 2 lids!).

Hi Ralf,

I just checked where those things are located on the building, but I haven't found them yet.

I had a 1991 35i with a 2.0L engine (2E).

They are located UNDER the exhaust manifold on the engine block!
I mean today (it's been a long time!!), that there are three or four lids sitting there.

You can only access it from below: So, remove the driveshaft. Take off the exhaust pipe. And then, get ready to use your skills!

Hi,

Okay, so the material of the new lid is already quite thick compared to the rusted-through . At least I'm not the first person to have this problem .

Sure, here is the translation of the text from German to English:

"Hi,"

Now, my father's engine has also had a problem with the block (and it happened in Austria - €160 for the replacement). So, if you ever replace the head gasket, just throw these small parts away!!!!!!!

Hello,
Why is yours working better after the belt replacement?
Unfortunately, my Audi 80 TDI with 290,000 km on the odometer can't reach 200 km/h. It never has. The speedometer usually shows around 185 km/h.
But I have a problem.
Sometimes I feel like it's a bit sluggish, almost as if the handbrake is slightly engaged. After a restart, or sometimes even without one, it runs normally again.
What could be the reason for that?
It would be great if you could help me with that!
(Sorry for typing this directly into your topic.)

Have a nice Saturday evening.
Regards,
Sausage blinkers[/quote].

Hi Wurstblinker,

In our Audi, the injectors are new. This might explain (at least partially) the good performance. The car has also been driven very carefully! The magnetic valve and hoses are also new. However, the fuel consumption is surprisingly not that great -> max. 1150 km per tank (60 liters). My Passat is considerably more economical with at least 1500 km per tank (70 liters) (-> well, I also drive extremely economically ).