Another Rookie 3.0L rebuild

[jdbunda]

Had a few spare minutes tonight and got the shims and thrust plates removed and the chain boxes loose - now I'm in high cotton!


Sent from my iPad using Tapatalk

[jpnovak]

John, I see you are making progress working late in the garage...

I am sure the next update will show the heads off.

[jdbunda]

How does he do it? Jamie, your predictions are uncanny.

I got the heads and chain boxes off tonight. I have to say, the way those barrel nuts come loose feels a lot like a stud shearing, the first couple were a little unnerving. Fortunately, it wouldn't have mattered, as everything is going onto a new case with new studs anyway. Everything came off without incident. Look Ma, no heads:



Pressing on!

[jpnovak]

OOOH. YOu have the fully threaded 993 dilivar lower studs. Those are the good ones.

So, Stock pistons. I can not tell if they are alusil or nikasil from the pictures. Stick a magnet to the cylinder inside wall and see if it just drags (magnetic). This is the way to accurately distinguish between the two. There is quite a bit of carbon as expected with the webers that had questionable jetting.

Next up, pull the cylinder tin and start removing the pistons from the rods. Make sure to keep each piston with its mating cylinder.

[jdbunda]

Yes - I noticed that the exhaust side studs were different from intake side and were threaded all the way, couldn't recall what kind those were, but I remember reading about the different stud types. I also assume they aren't re-usable? If they are, I am guessing one of those stud extractors should be on my next Pelican order.

So - a magnet just slightly drags in the cylinder bores. Good news or bad news?

[michael lang]

Originally Posted by jdbunda

I am guessing one of those stud extractors should be on my next Pelican order.

You could do that, I bought one for my recently completely rebuild. I bought the MAC Tools stud extractor from the MAC guy that comes to the dealership I work at just for that job. Never could get a good grip on the head studs, I ended up using two nuts, tightening them together as tight as possible and backing out the studs that way. Worked really well and was a simple solution to the problem. Just remember that heat can sometimes be your friend but patience will help you from making a mistake.

[jdbunda]

Thanks for the heads up on the removal tool, Mike. On consideration, I think I am just going to leave the studs in place and repair the case afterwards, so removing them won't be necessary.

Today I got the cylinders off, and bagged per Wayne's instructions. The only one that gave me trouble was #4, which took some persuasion. The good news is I have Mahle Nikasil cylinders. Everything so far looks to be in great shape.

[jdbunda]

Got my first piston out, figured out the trick to removing the little circlips and wrist pin. We'll see how easy things go on reassembly

I have also started some cleaning, running some stuff through the ultrasonic cleaner I picked up after reading the thread here about them.

My stock pistons are a little crusty, I think my webers were running rich. Other than that, they seem in good shape. Thinking I will ceramicote the crowns before I reinstall.

I feel like I am making good progress, but duly note that I am only on page 39 out of 200 in Wayne's book...

[jdbunda]

Pistons are all out. Thanks to Jamie for the help on tools and technique. As it happened, I recently picked up one of those $6.99 needle nose pliers assortments from HF, and the one with the long narrow jaws was perfect for grabbing the wrist pin circlips. Only a couple were stubborn, and I did figure out to turn them with a pick to get the ring gap where it made removal possible. One of my wrist pins was a little stubborn - I put a 16mm deep socket against the pin and tapped it out. Fortunately, the pins on #3 and #6, where the front engine plate is in the way, came out easily by pushing with a plastic screwdriver handle. I wrapped the exposed rod ends with shop rags to keep them from clanking against the case openings. Cylinders and pistons are all labeled and bagged, calling it a day.

]

About ready to crack this lobster!

[jdbunda]

Today was the day for the ceremonial case splitting. Like most things, though, a few paragraphs in the book easily expand into many hours of work. The first order of business was the crank pulley, which I did not expect to be a problem. Just fire up the impact wrench and off it comes, right? Well, after banging at it for a while, it was pretty clear my wimpy HF impact wrench on my pancake compressor was not up to the task. So I found the flywheel which had already been removed during the engine drop, mounted it back up, and cobbled up a flywheel lock out of a scrap of metal, similar to what Wayne shows in the book.



With this setup and my breaker bar, the pulley bolt finally squeaked loose. Removed the flywheel, intermediate cover, acorn nuts and through bolts. I was giddy with anticipation as I took off the perimeter nuts, found all 22 of those, and got the nut inside the chain box opening. Odd, the book says 15mm but mine was 17mm. Beefed up for the 3.0?

Anyway, a few thwacks with my rubber mallet, and it was obvious I had found all the nuts, but those internal studs were tenacious. It was obviously loose, but just not wanting to come apart. I was a little timid about whacking it too hard with my mallet, but with some text message advice and some tenacity of my own, I finally got the o-rings on the internal studs to let go (at least I think that was what was holding it).



The exposed bearings in the removed case half look to be in good shape, which bodes well for just moving everything into the other case. Calling in jpnovak to have a look though. We will likely pull one of the rods and inspect those bearings for signs of trouble, but I am optimistic after seeing the mains.



Meanwhile, I have also been parts cleaning - running lots of stuff through my new ultrasonic cleaner - valve covers, chain boxes, etc. it does a pretty good job with water and a cup of Dawn.

My replacement case was shipped to me in a big plastic storage tub, which I am using as its dunk tank. The case halves each spent a few hours soaking in that, followed by brush scrubbing and dry with compressed air. I need to scrub some more with some more powerful solvents, get the mating surfaces clean, make sure the passages and squirters are clear, and so on. I have a lot of parts cleaning and inspection in my immediate future.

In the coming week, after determining the current state of the case internals, I need to get my parts order in for studs, sealant, gaskets, etc., and get a bunch of stuff off to powder-coating. Feeling good about my progress at the moment!

[michael lang]

You should feel good about your progress. As far as parts cleaning is concerned, even after you have cleaned everything you think you needed to, there is still probably more cleaning you could have done. After having finished my top end rebuild, I periodically have second guessed my decision to have split the case halves to get into the crank shaft, connecting rods and bearings. Probably isn't going to make a difference in the long run, it's just part of the same sickness we all share.
I totally agree with you about the amount of time things take as compared to the way it's described in Wayne's book. I would start out thinking I could knock a relatively small task out in an hour or less and next thing I know it was three hours later and I still hadn't finished what I set out to do. The problem is while you're in the middle of doing that one item, you come across something else that is directly related to what you are doing and at that moment is the best time to address, clean, fix or replace that secondary item which ends up taking more time because you were not ready with the right tool or part or cleaner to bang out that item.
I actually had a lot of fun and developed a whole new level of understanding of how my car worked which I feel like will help me tremendously when I start going back to the track. The next time I do this I will do a complete rebuild but be much better prepared at what is supposed to be done.
Keep plugging away, you're doing great!

[mreid]

John, looking good! I am also using an ultrasonic cleaner for me 3.0 rebuild. Works great! Good luck with the rebuild.

[casor]

Originally Posted by jpnovak

OOOH. YOu have the fully threaded 993 dilivar lower studs. Those are the good ones.

So, Stock pistons. I can not tell if they are alusil or nikasil from the pictures. Stick a magnet to the cylinder inside wall and see if it just drags (magnetic). This is the way to accurately distinguish between the two. There is quite a bit of carbon as expected with the webers that had questionable jetting.

Next up, pull the cylinder tin and start removing the pistons from the rods. Make sure to keep each piston with its mating cylinder.

JP - can you explain to me why the fully threaded studs are "the good ones"? I really don't get it as it would seem to me that those have hundreds more stress risers and therefore more potential to break than would a smooth, partially threaded head stud.

-Confused in Boyertown.....

[jdbunda]

Doesn't make sense, does it? Maybe because they aren't shanked, there is more material in the studs? Page 84 of Wayne's book shows the different types, and it would seem if Porsche used them on the 993 and they stand up to the stresses that more powerful motor makes, they are "better." I did a fair amount of reading about studs, and there is a surprisingly high religion-to-science ratio in opinions about them. Lots of anecdotal evidence, but not much out there other than statements like "I had xxx studs and one broke", "I have always used yyy studs, and had no trouble", and so on. There are also a lot of variables here - mag cases in the early motors, aluminum later on, and so forth. The thermal expansion properties of delivar seem attractive on paper, but they do seem to show up a lot more frequently in the broken stud stories.

As an aside, I will be using Supertec studs for this build, they should be here any day.

[casor]

I have Racewares in two of my engines - one on the road again now - but for no other reason than I have never heard anyone having issues with them and that just about every Porsche guy I know of - mostly the old school guys - recommends them.

Again, back to the original issue, all those thread indentations just seem like they would cause problems....

[frankc]

Hi John,
Subscribed as I just discovered a 2.4T motor I purchased is going to need at least a top end rebuild. I have the engine on a stand and down to a long block at this point - not far behind you. I highly suspect I'll be seeking Jamie's advice as well on this one.

[jdbunda]

Hey Frank - hope your build goes well! Taking the heads apart this weekend if I can find the time.

[silverc4s]

Hey John!
Subscribed, finally. Sorry I have been kinda wrapped up in non-Porsche related issues since you got started on this interesting project.
You're doing great, keep it up!

[jdbunda]

Hey Bill, welcome, and thanks for your help yesterday! Bill came by and helped me disassemble the heads, we got the rockers and cams out and cam towers pulled off. There was one rocker shaft bolt that simply. would. not. budge. I have hex key sockets, but there is not enough clearance to get a ratchet head in there, and my little HF hex key was not going to get it done. Thanks to jpnovak for what perhaps should have been the obvious solution - a long extension through the other rocker shaft holes, the entire length of the cam tower - doable once all the other rocker shafts are out. Thankfully, the other ones came out easily.

For the obligatory update photo, here are three of the heads reposing on my motor parts shelf.



My plan is to leave the bottom end alone, so barring disaster, this officially concludes my disassembly!!! Time to start climbing back up the mountain. Next up, parts cleaning and coating, and heads off to get some love and injector ports.

[jdbunda]

I just sent my heads off to Craig Garrett (cgarr on this forum) for a going-over, and to drill the MFI ports for my injection conversion. Let me just say that packing the heads for shipment is not a task to be taken lightly. I probably spent more time on this than any other individual chore in my rebuild, except for maybe getting that last rocker shaft out of the cam housing.

I also sent my fan and housing off to Mark Motshagen (mark motshagen on this forum) to have my fan reconditioned. It's cosmetic, but the fan is such a focal point of the engine, I decided I wanted it to look nice. I was really impressed by the killer pics I have seen in various threads of the fans that Mark has done.

My Supertec studs, gaskets, and sealant kit are here and waiting - thanks, Henry! Looking forward to putting this thing back together, but it's kind of a waiting game for now.