New to Passat TDI...what damage is expected from blown headgasket (or is it really the headgasket)?

[Drewser]

Have owned several MKIV Jetta's along with a MKV, but never owned a Passat. Just replaced an engine on an 04 Jetta Wagon, so that's about where my experience lies...intermediate? A mechanic friend called me about a customer with an 04 Passat TDI with a blown headgasket who doesn't want to fix it. I am considering buying it for a few hundred at scrap value. What are my gotchas? Can I replace the headgasket and rebuild the head or am I looking at a new (used) engine? Can get a used engine with about 90k miles on it for around $2200.

Here's what I know about it. Has just over 300k miles, bad headgasket, water pump went out and fan clutch broke. Dipstick tube melted, so engine got pretty hot. I don't know what order things happened so could be some cause and effect there. Mechanic said it still drives nice, just not far obviously as it overheats. Interior is in great shape but is an ash tray...cigarette ash everywhere, under seats, etc. We'd pull it all out and clean it, I think we could get it livable. Try some of the internet tricks for smoke smell. It would be an extra car...my 20 yr old thinking of using it for commuting all over town for his job, then I have a couple kids coming to driving age soon.

Interested in specific thoughts related to Passats. What do I need to be looking for that a ALH/BEW guy wouldn't expect?

UPDATE: mechanic diagnosed headgasket based on exhaust in coolant. Maybe EGR cooler instead? See post 6 for update.

 

[oilhammer]

Amazing what the addicts will spend on that nasty habit instead of take proper care of their cars (I see some really bad ashpits here sometimes, and now more recently the pothead vehicles.... yeesh!).

Anyway, short answer: it will get expensive. Long answer: google "BHW balance shaft" as that will need to be addressed, too. $2200 seems ridiculously high for a used engine, even a BHW. I have one I'd sell you for half that, LOL. (it isn't for sale, just sayin).

There are certainly lots of other things that have been neglected. Pulling the head off is not a huge deal, though. But if it got that hot, it probably is going to need a lot of work.

I love my B5s. I've cared for them since new, they are great cars. But they are FAR easier to KEEP nice than to MAKE nice, if you understand my meaning.

 

[Drewser]

Thanks OH. Sounds like a used engine may be the way to go. I'll do some reading up on BHW balance shaft too.

I started adding up the cost of headwork, timing belt/water pump, cam/lifters, and anything else the engine might need at 300k miles and it seems to quickly be going past the used engine mark (even the apparent high mark posted above). Though if I bought a used, I'd probably do timing belt and water pump on it before I put it in anyway, and may even do cam and lifters depending on condition. So maybe some of that balances out...

As a side note, I joined this site with my first, brand new TDI in 2002. I could barely change my own oil. Last week I swapped engines with my son. I have gotten more enjoyment from learning and working on TDI's than just about anything else in the last 20 years. Feels like there's always something else to learn...

 

[Drewser]

What are the auto transmissions like in these? Would it be a time bomb at 300k? Are manual swaps available for these like the A4's?

 

[Mozambiquer]

I'd verify it's not the egr cooler first, i got a Passat with a "blown head gasket" but it ended up being the egr cooler. I'm still running it, but now have two more b5.5 Passats.
The transmissions aren't quite as bad as the 01m, but they aren't the best either. You can get a manual swap from Dutch auto parts, i think there's a few other guys who offer them as well.

 

[Drewser]

I'd verify it's not the egr cooler first, i got a Passat with a "blown head gasket" but it ended up being the egr cooler. I'm still running it, but now have two more b5.5 Passats.
The transmissions aren't quite as bad as the 01m, but they aren't the best either. You can get a manual swap from Dutch auto parts, i think there's a few other guys who offer them as well.

Your post is timely. I just asked the mechanic what symptoms it was showing and what they did to diagnose. He said, "we could see exhaust coming out the coolant cap and that it had overheated. At that point we just figured it wasn't worth work on the top end based on mileage." That got me thinking what else could cause exhaust in the coolant, which led me to EGR cooler.

So here's a theory: water pump went out, which caused engine to overheat and caused hot coolant to blow out EGR cooler. They said they know water pump is bad, and said fan(s) is/are bad. Assuming this transaction goes through, I'm thinking next step is to check compression on the cylinders...if that's good, pressurize the coolant system and see if it holds or if I can determine a bad area. If that leaks, does that lead to the EGR cooler being bad?

 

[oilhammer]

The ZF autoboxes are fine, they just do not like neglect. There is a weak spot, the torque converter, which is easily replaced on its own. I'd say they are better than some, worse than others. Mine are both nearing 1/4 million miles and still working just fine. ZF says flush the fluid every 100k km (about 60k miles) which is what I have done on mine since new.

 

[Mozambiquer]

Your post is timely. I just asked the mechanic what symptoms it was showing and what they did to diagnose. He said, "we could see exhaust coming out the coolant cap and that it had overheated. At that point we just figured it wasn't worth work on the top end based on mileage." That got me thinking what else could cause exhaust in the coolant, which led me to EGR cooler.

So here's a theory: water pump went out, which caused engine to overheat and caused hot coolant to blow out EGR cooler. They said they know water pump is bad, and said fan(s) is/are bad. Assuming this transaction goes through, I'm thinking next step is to check compression on the cylinders...if that's good, pressurize the coolant system and see if it holds or if I can determine a bad area. If that leaks, does that lead to the EGR cooler being bad?

I wonder how they know the water pump is bad? It's pretty common for people to misdiagnose that, especially if they're not used to the b5.5. air in the system from exhaust gasses can make it seem like it has a failed water pump. If you have room and can get it cheap, I'd do it...

 

[Drewser]

"have room" is relative... But no HOA so... Lol

 

[Mozambiquer]

"have room" is relative... But no HOA so... Lol

Haha, I know how that is... I have 7 diesel vws and a total of 10 cars right now... Thankfully no HOA, as I live in the country.

 

[Drewser]

Well, I bought it for $300 last night. Guess I'll be digging into it soon. But first need to detail the inside...cigarette ash EVERYWHERE.

Oh, and a partial bottle of gold GM coolant in the trunk, which concerns me...

 

[Mozambiquer]

Well, I bought it for $300 last night. Guess I'll be digging into it soon. But first need to detail the inside...cigarette ash EVERYWHERE.

Oh, and a partial bottle of gold GM coolant in the trunk, which concerns me...

I'd say, no matter the condition, that's a pretty good deal! Keep us updated as to what you find!