Lets start to get to the heads...first step is to take the cam covers off. Note the way the oil connection to the cover...



Off comes more parts getting ready to remove the cam towers..



The cams pull out of the back of the engine. There are two access panels to support the factory timing tools and the cams just slide out. My cams appear to be in fine shape with no real pitting, grooves or marks...



I don't know if you remember this conversation but the 993 uses a friction fit sprocket on the cam chains rather than the old method of a keyway and an indexed sprocket. I want to backdate the sprockets so I don't need the factory tools to time the car (and I can set the timing to what I want). I was worried about getting a keyway cut since the later 993 cams did not have one...but guess what mine still have the keyways!!



So off comes the cam carrier that spans the heads. Lots of bots with lots of locktite...good **snap* noise when you undo them!



Here is a suprise....whatever person was on the Porsche line when my engine was build almost fully stripped out the insides of this bolt that holds the cam carrier in. You can see the inside being rounded out. I had to gently hammer in an allen key into the bolthead which just gripped enough to get the bolt out...that caused some swearing! (and sweat...not a good place to have a bad bolt). Turns out that on the OTHER side there was another one...which I just managed to get out. Put down a note in my book to order new bolts......



Here is part of the world famous SAI ports. Mine were clear in that they blew air fine...but you can see all the carbon that has blown up into the head. This location is at the top of the head just above the little port that comes out just behind the exhaust valve.



A close up of the tiny hole that is the SAI passage. Its tiny and mine are covered in black caked on carbon/soot. This is not going to be easy to clean and all the passages have to be cleaned...



Here are all three heads still bolted onto the engine. You can see the SAI port "smuges" on each of the heads....



Here is the engine once the heads are off....it getting smaller and smaller...



And finally all the heads are off the engine and we are left with the case and P/Cs.



Next posting? I will do a short one taking one of the heads apart and we can look closely at the valve guide wear...I will try to measure it to see how much I have.

Cheers,

Mike

 

Mike, how long do you plan on taking for this project, start to finish? Do you have any mods planned while you have it apart? RS cams, etc?

 

The standard qutoed time is about 40 hours for a professional mechanic to do a rebuild. I have heard to double it for a first timer. I think I am worse than that. I started to log the time but then got lazy. I will put a sheet up in the shop to track the time...

I am not sure about any mods...the cams etc are in great shape. The problem is the whole thing should be changed as a unit, i.e. cams/valves/P/C's/software. I don't have that kind of money...these cars are really expensive to modify and I find that, since I drive a lot of time on the street, that I have plenty of power to get myself in trouble (I might get flamed for this). On the track its different but for the limited track hours any mods are quite expensive/hour.

I have some inquires out about doing some light cam mods etc. but I also have to pass emmissions etc...

Cheers,

Mike

 

Wow, those pictures of the SAI ports really gives you a feeling for the carbon buildup. I wonder how effective the flushes real are with that level of buildup (note: they are not even clogged completely).

 

Got ya. Still will be nice peace of mind knowing you have a fresh top end.

 

Hi Mike,

I think you may have partially amnswered my question on Part II. My understanding is that this is not too expensive to do.

How do you keep track of all the parts? I would be paranoid about losing or mixing up things!

Cheers,

David

 

I bought several large plastic tubs and plenty of sandwich and freezer zip loc bags from Costco. On every phase I bag the parts/bolts and take lots and lots of pictures ( a couple of hundred high rez ones so far). I mark all the bags with an indelible marker where the parts belong and the side of the engine. It remains to be seen if this works on the assembly cycle.

Gerry Woods would just throw all the bolts into a large bin and then pick them out again. I could not do that...I am trying to put it together the same way as it was before I took it apart..and that requires tracking.

This is one of the reasons it takes so long for use newbies...you are paranoid about mixing stuff up. Some parts you do not want to mix up...like the rockers since they have wear patterns that match the camshafts, or the pistons/barrels etc. Other parts do not matter so much because they can't be mixed up (like the chain covers..).

Cheers,

Mike

 

Exactly what I was thinking! A flush might have even caused bigger problems -- knock loose some carbon, maybe to become lodged further down the passageway.

 

'the flush' really only is the first attempt at clearing the SAI trouble codes. Typically best to try the least expensive methods first. Not always, but in this case, I feel.

 

Hello there. I've been lurking here for about 2 months now. I don't even have one of these cars but I do plan on getting one in next year or so....anyways, to get to the point....excellent work you are doing here Mike, but I decided to chime in with a chance to give you a piece of advice.

I know I'm a total stranger here but for some legibility, I'm a quattro guy and have had Audis and worked on them myself for 6-8yrs now, but its totally up to you to accept this or not. perhaps cosult others. So, by looking at that SAI port, I would suggest, once you clean it real well, you take the grinder in your hands and polish that port to a mirror-like finnish. Even better yet, if you could have it lined with Teflon coating it would be the best. The reason I suggest this, unless there is already a better method for preventing this clogging, is that I and many other have had had a bad experience on Audis V6 12V engines. The EGR(exhaust gas recirculation) port that goes from EGR valve through intake manifold and exits just after the throttle body was so small that often got clogged with carbon buildup, which would throw a CEL(check engine light) and help you fail emissions. The best solution was to take IM off and polish that port to a mirror finish. When I did so, it was good for next 3 years, after which i sold the car but even the guy that bought it never had problems to date. Mind you, it used to clogg every year or so if cleaned and left as is(abrasive alluminum).

Hope this helps and good luck with the rebuild, its quite an experience and you'll find so much more joy in driving the car afterwards!

 

That sounds like a great idea...I will take a look at the size of the hole once its all cleaned up. I will also post pictures of it cleaned up and perhaps pictures of the pathways the air follows so everyone has a good idea of the exact passageways the air goes. I might as well since its all apart anyways...

Cheers,

Mike

 

Mike, this is really impressive. I admire your courage.

 

Maybe I am just too stupid to realize how stupid I am.........

 

So wait a minute, I'm confused here.
Does the air from the SAI pump come throught the cam carriers or what ever they are?
it appears to be so... or am I wrong.
I'd like to know the routing of those passages. I'm doing a flush on my car. PITA. First they are flowing
well, the next day they're clogged. Must be that carbon carp up in there.

 

Mike, congratulations for the job already done!! I was not a lot on the internet since a few weeks. Gee I almost missed you work reports! I started today to read all from the beginning. Once again !
You are at a stage I'm thinking about for a while. But to my opinion, with about 75k mi, my engine doesn't need it yet.
But for sure reading your "report" will give me more guts to go ahead with it when needed. A good point is the keyway on the cams. I hope my 96 4s have them too, because I'd really like to make that valve timing adujstment mod.

Keep up posting updates on your progress, you have another fan eating popcorns and waiting for the next report

Cheers