Getting started, dropping the engine and superficial stripdown

From pcarworkshop

The engine rebuild posted here are the result of an engine rebuild projects I did over a period of four months. My car is a 1996 993 Targa with a 3.6L Varioram equipped engine. The car had 75,000 miles at the time, consumed one liter every 800 miles, and had check engine lights for continous misfires. The misfires also result in a rough idle with a **phut** **phut** type noise.

A leakdown test showed marginal valve sealing but the compression test was fine.

So, here is the car at the start of the project. I am positioning it in my garage..of course it took a good few weeks to prep the garage for this project. Its a typical case of "a" follows "b" follows "c"... I had to buy materials to build new cabinets to store excess stuff that was moved from another wall in order to tear down some shelves so there is extra room for a ....you get the drift!

Notice the nice 14" steel I beam that runs across the shop...that will come in handly later....

So, why use one jack when you can use FOUR (one smaller one is holding the nose of the transmission. I find this works great and my total lifting capacity is several tons.... ;-). It also allows you to tilt the engine back and forth to get it out. I found that on the later air cooled cars the clearances were very tight between the suspension components and all the parts hanging off the engine.

So here is why the beam is handy...just pull the butt of the car OVER the engine. Its safe and I don't have to undo any bodywork at all. Last time I dropped the engine I had extra hours of work to remove the bumper....this works much better!

Of course the engine had to be lifted up onto the engine stand. I fabricated a stand from some heavy tubing and an existing 2000lb stand that I had. Its not going anywhere and I got to brush up on my shakey welding skills.... ;-). I also bought the proper engine Yoke and assembly. This part is pretty expensive ($400+) but its worth it. I feel secure that the engine will not be stressed too much since the mounting point is completely flat to the end of the engine, and its strong enough to take the weight.

Here is the famous SAI pump and valve system. The air gets sucked from the large hose on the left which is connected to the air filter box, through the pump and into the distribution manifold. You can clearly see the plumbing. Once into the distribution manifold it goes to two aluminum tubes that are connected to the rear of each of the cam towers.

The Varioram is off and you can see down the intakes. They are coated with a bit of fuel varnish which will be cleaned up but they are pretty clean.

I am getting a bit tired working on the top so FLIP and its bottoms-up! This beats lying on my back under the car let me tell you...I removed the heat exchangers/mufflers as a single unit. The stand is great!

Okay, all gone...I did not take a close up of my ports but I know the SAI ports are still open but marginal but there is lots of gunky black carbon/oil buildup at the base of the exhaust valves...not a good sign..the SAI ports are almost all plugged up.

Okay, back to the top. The plastic intake runners are next that hold the injectors etc. I will send the injectors out to be cleaned and checked...the intakes also should be checked for microcracks...this can cause vacuum leaks and problems down the road (yes, pun intended).

More sheet metal is coming off...notice the leaves built up at the edge of the head. I found this at both sides....

The upper plastic baffle comes off. The shields/manifolds/mounts are all interrelated and interconnected...typical German engineering...

The AC mount comes off once the engine mount is off. As I said before, its all layered.

Well the small oil filter was really stuck and my wrench kept slipping...I tried the rubber trick, the tape trick to no avail. But when the engine is on the stand its amazing what you can do drilling a hole and using a long allen key....zip its off! I changed this filter before and remember not tightening it up too much so it must be the heat cycles.

Okay, now the engine is out and stripped down to the block.

So far I have broken two bolts. One held down the plastic intake to the heads...it went soft on me. There is a bit of stud left hanging outside the head for the machinist to play with. I broke another from the sheet metal hear the front engine mount likely because of the heat from the exhaust. That one I have to fix and I am not looking forward to it.

Links to Rebuild Tour

1. Getting started, dropping the engine and superficial stripdown
2. Checking the default timing and Cams
3. Looking at the heads and the SAI passages
4. Valve guides, valves and carbon
5. Further Dissassembly
6. Exploring the SAI passages
7. Cleaning and getting ready to put it all together again
8. Rods and last minute checks before putting the case together
9. Sealing the case (or tomb)
10. Putting the pistons/cylinders back
11. Camshaft timing Part I
12. Camshaft timing Part II
13. Messing up a clean looking engine
14. Not quite there
15. Cranking it up