Heyyyy guys,

So for the life of me I can't seem to find a service manual anywhere for a 1994 100CS 2.8L V6 SOHC 12V vehicle unless it's in Russian.

I have a leak that appears to be wet at the cylinder head interface so I wanted to tackle the job of disassembling the engine and checking the head gasket, valve seals, etc. as well as possible head resurfacing and so on.

If anyone has any information available concerning torque specs or knowledge getting down to the cylinder head I'd be very grateful! I was also wondering if the '96 A4 2.8L V6 30V has identical properties to the '94 100 2.8L V6 12V or not?

Also, are there any funky tips or tricks out there to replace the special Audi timing tools or is it best to shell out the couple hundred bucks to get the 3242 & 3243 tools for the cam adjustment?

 

Try www.12V.org site for information on the engine. The '96 2.8L V6 is probably an AFC engine, which is different than your '94 2.8L V6 (especially w/ 30V). It is highly recommended to use the camshaft and crank locking tools when servicing the timimg belt. You can easilly locate the set on eBay for a decent price.

 

Thanks for the info. Also for any people looking for info in the future, here's another link that has lots of information about the AAH engine with torque specs and pics:

http://www.softcar.ru/UserFiles/File...udi-1993-d.pdf

I use that combined with the next link below (for an AFC engine) to cross reference bolt locations and double check specs since they are slightly similar:

| Repair Guides | Engine Mechanical | Cylinder Head | AutoZone.com

 

LOL im facing the same job as you. Too bad you are way up north and in way up in North GEORGIA. removing the intake is easy. removing the head you need large torq bits- i think 15mm? 17mm?. the cam will require locking tools. In a simpler engine you could get away without but this is OHC v6 so- no. One thing you could do before going at the head gaskets is to eliminate the Valley pan gasket as the source. It is easy to do, i did it in 3 hours or so the other day in my own last ditch attempt to not have to do head gaskets. While doing head gaskets you should do valve seals, timing belt, water pump and thermostat.

 

Glad I'm not alone! Ya I just saw those head bolts this weekend and was wondering what they were, but finally my locking tools are expected to arrive this week then I can start removing the timing belt! I also have a massive oil leak somewhere that I haven't been able to pinpoint quite yet :/ seems like I've got a lot of work ahead of me. How far have you gotten so far?

 

It is still in running condition as I keep it as a spare car. My DD is not nearly as soldily reliable as my trusty Audi. I dont expect to start the work all too soon as i need to be more comfortable taking my spare car out of service. Im very curious as to your adventure and would love to follow your progress closely. Maybe that will give me the courage to get started. Wifey complains about the parts bill already- she should be happy about the lack of car payments and ad valorem tax and insurance premiums.

Where is the leak? Are you sure it isnt coming from the Valley pan gasket?

 

You are planning on replacing the timing belt, water pump and thermostat while you are in there right?

 

Ya it definitely isn't the valley pan gasket, it was replaced before with no luck, also the engine block is coated with oil everywhere from the head-block downwards.

I just got the heads off now and am working on cleaning the engine. The oil is just cooked on though, makes it look like the engine is naturally a black colour. I've been chipping away at it with a flathead for the last couple days and can finally see the silver!

The head gasket also has an orange seal around the perimeter to prevent oil from escaping the veins of the head and this seal is completely gone on my engine. I can see the outline of orange but it feels like metal when I touch it, also some areas the seal is just burned away and you can see the bare metal behind it so I'm hoping this is the culprit.

I'm sending the heads out for resurfacing and cleaning tomorrow or the day after for good measure. I'm also replacing all the seals that I've taken off: the head gaskets, valley pan gasket, cam seals, valve cover seals, exhaust seals, air intake seals. The timing belt and water pump are relatively new though (about 10,000 km) so I'm going to reuse those but replace the thermostat. All the bolts I've removed have been soaking in an anti-rust solution to clean them all off to which is working really nicely as well.

Only thing I'm not sure of though is the pistons have some black flaky material coming off, I can't tell if it's old carbon deposit build up or if it's some sort of coating off the pistons? Do you know any good ways of cleaning the pistons as well as the block surface without damaging or scratching the surfaces?

If you ever decide to tackle the project I'd be happy to help if you have questions! I haven't been able to find any information online for taking these heads off but I've definitely learned a lot in the process.

 

Since the block is cast iron, you can use a med/soft circular wire brush with an electric drill to remove the debris. For the pistons, you can do the same (just use lighter pressure). Also, plug the coolant jacket passages to prevent debris from falling into the cooling system before cleaning. To prevent damage to the cylinder walls, make sure you rotate the piston so it is flush with the head surface before cleaning. I have previously used this procedure sucessfully whenever I removed the heads.

 

I've got the car completely back together and got it started. I'm still a bit concerned about it though as it sounds like the timing belt is noisier than usual and also there is some white smoke that looks like it's coming from the heads at initial startup.

I just drove the car around town for about 5 km or so and it seems like everything is okay. Coolant temperature remained at a very good temperature, oil temp was okay, no check engine lights or anything but there was still some light white smoke so I'm still concerned with it. Would you know what this could be caused by and also the loud timing belt?

Here's some pics of the cleaned engine: