1.8T DIY rebuild (desludge) photos
 

Just uploading some quick pics for now, will add a few more comments later....
if anyone's interested in a complete write-up, just twist my rubber arm.... ;-)

Sorry i didn't take any before pictures, the first one about 80% through cleaning the combustion chamber/valves give you only a partial idea of just how much crud was built up in there. the exhaust valves were especially hard to get clean, with some kind of very hard mineral build-up under the thick carbon crust that was on everything. but they came out pretty nice, don't you think?
The pistons and the top part of the cylinders also had quite a bit of carbon buildup, but that came off easy enough with some solvent (heating oil, diesel fuel works well too) and gentle application of a a fine brass rotary wire brush, and extra care remove all the debris with a combination of paper towels and air gun and a few sprays of solvent. finish with a little WD40 rubbed into the cylinders to prevent rusting until the engine is first started.

I checked most important tolerances and was very please to find that even after 180,000 km, there was insignificant wear on the cylinders, valves, lifters, cams, etc. not enough to justify replacing anything at this point. once cleaned up, you couldn't tell that the head wasn't brand new.

Thats as clean as i could get the valve cover (hard to get into the nooks and cranny's), and it was especially crusted with sludge. The oil pan was not as bad, but I'm glad i did it in spite of the trouble as there were a number of sludge chunks that were freed from the oil system power-rinse i did a couple of weeks previous. Glad none of it had time to get into the oil pickup tube.
The 'renu-engine' treatment works pretty well, from what i saw in the valve cover just before the treatment, compared to when i started this rebuild, i'd say about 80% of the sludge, at least all the 'softer' material, was removed by it, leaving mostly the older hard scale. The latter is surprisingly hard to remove even with solvent and a stiff brush.
When i was done cleaning all the parts, there was about a 1-1/2" thick heavy layer of crud at the bottom of the solvent reservoir (garbage pail) of my improvised parts cleaner.

By the way if you're wondering how to take the head off and get it back on the engine without taking the timing belt off first, the last picture should be a clue... its easier than it looks...

Re: 1.8T DIY rebuild (desludge) photos
 

This is the view as i was putting in the new turbo and exhaust manifold.
You can go to my "porting the turbo" thread for more info on the turbo.
It's easier to get it in place and bolt on the cat before dropping the head in.
I used clear high-temp manifold paint on the turbo exhaust housing (stainless) and compressor housing, with black on the (cast iron) CHRA. I also did the cat after doing a major cleanup on it, since its also stainless. added a stainless downpipe too.
The clear paint darkened quite a bit after a few hours of highway driving (as expected), but still looks much better than it would otherwise. the stainless exhaust manifold is now dark dull blue and I'm sure will be brownish-black by spring.
that's ok though, I'm gonna wrap those pipes with insulation soon anyhow.

Re: 1.8T DIY rebuild (desludge) photos
 

Here's what my manifold looks like after 2 weeks - yeah, those welds are cracked and it sounds even worse. i thought about re-welding them in place, but then odds are it would just crack again anyway, next time might be in the middle of winter- not fun. i seriously doubt i will get a refund on it, i may try to re-engineer it later.
because Stainless steel has a hight temperature expansion coefficient, and doesn't handle fatigue well (especially brittle welds), i kinda expected this, but really hoped the small size of the manifold would mean it would live a few years before this happened. Guess again (sigh). If i can find the right size SS bellows pipe, i might cut the 2 end pipes and weld in a short piece in them to absorb the expansion/ contraction and take most of that stress away from the collector welds, which will get some reinforcement too. I'd also have to do something about that back bolt which is impossible to get to.

In the mean time., I'm swapping back the stock one in. i should get my new DV in the mail today, so installing that at the same time least that will be a positive thing.

Strangely enough, i also found that the oil pressure sensor failed and is leaking oil into the electrical connector. thankfully, thats only a $4 part and very easy to swap.

Mostly now i am waiting to get the new MAF sensor i ordered, tho old one died last week also.
wonder what's going to fail next.... :rolleyes:

Re: 1.8T DIY rebuild (desludge) photos
 

How the hell did you attach your turbo to that manifold? I see no way to get the other 2 bolts in?

Re: 1.8T DIY rebuild (desludge) photos
 

Good observation- basically I had to cut a notch into the hole for the left bolt in the flange so i can slide it on with the bolt already in the turbo, then just tighten it. the back one you cant see there's no way to get a wrench on it with it on the engine, you pretty much have to mate manifold & turbo together first and install them as a unit.

I did manage to get the manifold off without removing the turbo ( to get the stock unit back in) but it was a real B*** and took forever. I had to sacrifice a crescent wrench and make a "customized" tool, and even so it was nearly impossible.

Re: 1.8T DIY rebuild (desludge) photos
 

Thread moved to DIY! Thanks for this great info

Re: 1.8T DIY rebuild (desludge) photos
 

Sweet, is there any real power difference with that turbo manifold? From what I understand, there is a cast manifold just like that for a little more doe on ebay.

Re: 1.8T DIY rebuild (desludge) photos
 

Unfortunately i wouldn't be able to say because i was changing the turbo and doing a lot of other maintenance at the same time. Before the work, the engine had been running essentially normally aspirated only ( dead turbo), for as long as i have had it. There was a massive increase in power after the new turbo+manifold etc, but certainly most of that improvement is from finally having a working turbo, and any small contribution from the manifold is impossible to differentiate.

I don't really expect the manifold to make much difference on a turbo engine, because of the back pressure the turbo creates, the manifold's "restrictiveness" is not as significant in the performance equation, at least in theory. I got the new manifold mainly because i wanted to replace 20 lbs of ugly cast iron with 5 lbs of very nice looking stainless steel, the price was right, and because i needed to swap turbos anyways, it wouldn't add any labor (or so i thought) :rolleyes:

The good news is i have been in touch with the vendor and they seem to really stand up to their "100% customer satisfaction" commitment -i sent them pictures and they offered a full refund. I'll let you know when the money reappears in my paypal account.

Also to note if you decide to get this manifold, don't use the cheap gasket between it and the turbo, during disassembly i saw one side of it had blown out, it looks like couldn't handle the exhaust pressure. Get the real Audi one instead, its only $5-anyways. Also, use plenty of anti-seize compound on the bolts & studs. i swapped all my exhaust hardware for stainless nuts & bolts, and the exhaust housing is stainless, which is a metal very prone to galling and seizing.

Re: 1.8T DIY rebuild (desludge) photos
 

Nice!

I hope you'll excuse me as I'm about to be completely off-topic, for people who likes such engine restoration pictures. There's a young car mechanic that bought a crashed Ferrari Testarossa and who's fixing it with his father (also a car mechanic): the car was crashed in the mid-90ies, and the previous owner couldn't afford fixing it. The car slept unused for 17 years in a scrap yard, and she's now rust-free and almost back to life!

A "best-of" of his pictures and his videos: tfpsly.free.fr/Divers/Testarossa.html