I vote to split. It really is a high return on the dollar spent to split when you are down that far.

Everybody votes to split, but isn`t it just a bad case of whileaminthere?
Besides, has anyone stories to tell about 911SC motors failing from the case? Since the case was not leaking, I am still not sold on splitting it.
Or, let us put it this way: If you had the choice between splitting the case on an otherwise healthy motor with 110,000 miles, OR installing a new set of P&Cs (with 9.3:1 compression), which would you do?

Aurel

I would do both. The cost/time to split is really minimal compared to the time to get there. That's what I decided two years ago. My crank was perfect, but I did replace all the bearings, seals, and the rod bolts with ARP.

just my .02


anyone know how to make the cents sign? :)

at 70k miles, I did the top end and didn't split but probably should have to check the layshaft bearing and replace layshaft chain gear... I was feeling already over my head...and running out of boxes and room in the garage to label and store parts... I had the full case of the "while you are in theres" as it was. I'm not sure this is any help.

oh, and that engine stand scares me .. careful when you turn the engine, things will get more out of balance as you build up the top and intake system, you might want to clamp on some additional outriggers

I'll be the first to vote not to split. You are correct that the bottom end should last along time. If you had good oil pressure before removing the engine and no reason to suspect a problem like oil leaks, then keeping the case together will save time and money. There is also the possiblility of messing something up when you put it back together. The only difficult thing I see is removing the headstuds without splitting the case. The rods will be somewhat in the way and you don't want dirt to get inside the case.

-Andy

I was in the same situation with 90K on my 3.0L. I had made up my mind NOT to split the case, then at the last minute I said, WHAT THE HELL. Man was I glad I did. Everything looked GREAT, except for 1 of the main bearings and both intermediate shaft bearings. All it takes is one small thing to mess up an otherwise good rebuild.

http://forums.pelicanparts.com/uploa...1192882313.jpg


http://forums.pelicanparts.com/uploa...1192882349.jpg

Aurel, I feel for you. I would've been tempted to keep my 130K 3.2 case intact. The "good news"? I missed a shift and was forced to split mine to replace rod bolts. Saved me a lot of time on the fence.

My bearings and crank were all good, but I too saw some wear on the intermediate shaft bearings, so in that regard, it was a good thing. As stated above, much of the cost is in the top end, it kind of makes sense to go all the way.

Update: Yesterday, I left my heads to Bob from Atlantic Anchor. Great guy, who offered to meet me half way on a parking lot. I know my heads will be in good hands. I also dropped my gearbox at bodymotion. They will redo all the syncros, the diff bearing if needed.

Now, some bad news: One of my headstuds is broken very close to the case. How in hell am I going to take it out ?? Tips appreciated if anyone has dealt hands on with that already.
http://forums.pelicanparts.com/uploa...1192887460.jpg

Other potential issue: One of my cam lobes has some nasty pitting on it. That is the only spot, but it concerns me. If I have to have them reground, I may as well do the 964 profile and use higher compression P&Cs, right? ;)

http://forums.pelicanparts.com/uploa...1192887736.jpg

Aurel

For headstuds removal, I have a heat gun that goes up to 540degF. Since the red loctite is supposed to melt around 325-350F, it should work. Anyone ever tried a heatgun? My plan is to first find the right conditions on a non-broken divalar stud, then apply same on the broken one, with a nut welded on it. I`ll have to find someone to weld that nut though...

Aurel

I didn't use my oxy-acetylene rig, but I did use a Mapp gas unit. A 540 degree heat gun, which I assume is electric, probably isn't enough. You have a lot of metal mass in the case to absorb the heat, which I think would make it tough to melt the Loctite. Get a handheld Mapp unit for $40 or so at Lowes or HD.

Yup, I tried and 540F isn`t enough. On the other hand, I created a little rig with an old headstud to remove piston wrist pins when they want to give a fight. It works great. I much prefer sliding them out with that device than hammering them with a screwdriver handle.

http://forums.pelicanparts.com/uploa...1192922105.jpg
http://forums.pelicanparts.com/uploa...1192922168.jpg

Aurel

I recently did a o/h on a 87 Carrera and made the decision not to split the case. It was a 97k miles motor. My reasoning was that I was building a 50k motor, which the way I drive is about 10 years worth. In 10 years I will probably (1) be dead, (2) be broke, (3) be single again, (4) be driving Aston Martins, (5) Own a new GT (6) decide Fords are better after all. :)

In otherwise it is a financial decision only you can make.

In mine I bought an in spec low mileage set of Nickisil pistons and cylinders, put in new rings, a set of 964 cams (about $660), new chains and some gears, all new valves and guides.

Good luck. I'm planning on doing a 150K mile 79 engine this winter myself. Will split the case on this one. All kinds of fun.

Take the case to a local mechanic that has a welder and some experience. Let him remove all your lower studs. He probably won't charge much.

Aurel, Dan above has picts of reasons to split... I mentioned the layshaft bearings and he shows a picture. And here is a very bad reason to split the case, it avoids having to say "yes I rebuilt my 911 motor.... but I didn't split the case" - this might not be a big deal to some... but I wish I would have split. I'll just keep good oil in there and hope for the best on the layshaft and mains. I say I would split now but at the time I was feeling way over my head as it was.. I'm more confident now... so I'm not saying to split... just telling some stories... maybe someone can come over and help out on the critical parts....

Subscribing for information purposes.

Good luck with the job and thanks for the info and pictures of the progress you are making!

Clean what's left of the stud, and weld-on a nut. With the right size wrench or socket handy, you might be able to remove the stud, immediately after welding. Remember the o-ring that's under the case through-bolt, right next to the work area.

Aurel.

You REALLY should split the case because:

You are spending a small fortune already, so why not go all the way.
You will know exactly in what condition your motor is in, when you are done.
You can take all the credit and pride in saying; "I rebuilt it myself"
You can do a better job at cleaning the inside as well as outside.
If something is wrong later, you won't be saying; "I should have split the case"


I debated over this same decision at length and finally decided to do it. I am very happy I did. I know my oil pump is in good order, all bearings and seals are new, and I learned about several types of sealants. It is not very difficult considering you will have to do more difficult things like cam timing etc.

Just my 2 cents,

MichelSmileWavy

For stud removal I used a bolt extractor kit that has a straight flite cutter. The straight flite cutter do not expand the stud into the threads. I did mine on a milling machine to get it straight and used mapp gas to heat the case.

#1 Reason to split your case
 

So you can send it to Ollies and have them make it look like this. . . :)

http://forums.pelicanparts.com/uploa...1181348799.jpg

Well, my case does not look quite that nice, but I`ll get there...I got a propane torch today.

http://forums.pelicanparts.com/uploa...1193098640.jpg

Aurel

is this the begining of MAP gas work on head studs.................. drum roll please...

my 2cents worth... peace of mind is only an issue if you plan to keep the piece for a mind = if you want to keep er' for 1+ yrs/3k+ miles, it will be a selling feature that it ALL was checked and what was needed was replaced. I have not done this as of yet, just my thoughts. I do have 3 engines about to go under the knife for different builds though which means zippo since I am still wet behind the ears as far as porsche engine building goes...but us BOTH have the Pelican board to hopefully save our buts if needed... :-)
Bob

I played with the torch tonight, and I got eight divilar studs without a fight. One unbroken is more tenacious, and the three left are the broken ones. My confidence is up, but I am not sure how big of a flame is best for really heating up the case...it did not get red at all, for the eight studs that gave up.

Aurel

If you have a welder you can weld nuts onto the broken studs. Makes quick work of them. The heat from the welding releases the loctite and the nut gives you something to grab.

-Andy

When you say that the metal did not get red, are you talking about the studs or the case. Aluminum will not get red and if your using a small plumbers torch I don't think you can overheat the case. I remember reading that you can hold the torch on the inside of the spigot for like ten minutes without overheating but I could be wrong.

Propane is not as hot as MAPP...

I got all the unbroken studs with the propane torch. Now, for the broken ones, two have over half an inch left. I am looking for the best possible tool to grab them. Has anyone tried one of those?
http://forums.pelicanparts.com/uploa...1193277723.jpg
Aurel

no, but I've heard that when you are heating the case around the stud, if you have someone continously apply torque to the stud, you can feel it come loose.. this avoids more heat than necessary... I was lucky...the machinist came over to my house and brought his Snap-On stud grabber tool that looked about 50 years old and used 1000 times, and 2 foot long wrenches and they all came right out.. we had the Mapp gas ready but didn't really need it. I replaced what I had with all new steel.

Aurel,

I have the tool you pictured but I also purchased a collet that you tighten down on studs. It worked great and can get close to the case. I got it at thetoolwarehouse.net http://forums.pelicanparts.com/uploa...1193311792.jpg

I'll get that tool, it looks like what I need;
Update: Bob from Atlantic Anchor sent me some pictures of two corroded valve seats he is going to replace. I bet the corrosion, which also caused the headstuds to break, occured when I was driving the Porsche on my five minute commute to work at my previous job. That was a dumb thing to do, because oil did not get hot enough and must have trapped water; Little did I know at that time...
http://forums.pelicanparts.com/uploa...1194169912.jpg

Aurel

I would be surprized if water sat on the seat causing the "corrosion" shown. All those parts get hot in seconds if not sooner.. Also I don't think some water trapped in the oil would cause the head studs to break. Was the stud that broke Dilvar?

had both models from Snap-On. Not the finest tool for the job imo.

I line bored case at Competition Engineering after splitting it. I believe it can be a tricky operation on our engines.


good luck

Little update:

I got the two tools depicted above, and was able to remove only one broken stud. There are two left in the case. It looks like I am going to have to go the nut welding route. And since those are divilar studs, I have read that only TIG welding will work. Has anyone had luck with MIG welding? I am also looking for a machine shop in my area that could extract those...close enough so I can avoid shipping the case.

Aurel

I'd look for a Porsche machine shop....you kill two birds with one stone. Have the studs removed, inspect the case, clean and do the oil squirters, etc. Even in Dallas, TX, a decent-sized city obviously, I ended up shipping all of my stuff to SoCal.

Verdon Tool and Die, in Blackrock? NJ is very good with Porsche engines... I have the address at the shop

All right Tim, stop spreading disinformation! :) :) :)

Verden Tool & Manufacturing Company 121 E Blackwell Street Dover NJ (973) 366-7510

Victory ! I extracted the three little bastards...and, in the process, I made a major Porsche discovery: I found the ultimate weapon to extract studs that are broken very close to the case, with no need to weld a nut: you buy a $14.99 nut extractor set from Sears, and the #2 grabs the broken stud and never lets it until it is extracted. The more you torque, the more it grabs. This is a lot better than the two tools discussed before, because it can get very close to the case, and does not interfere with anything in tight spaces. Wish I had gotten that from the start.

http://forums.pelicanparts.com/uploa...1195333933.jpg

Aurel

Aurel,

Looking at the Sear web site I can't see this tool, what the Sears item# ~~~~~~~~~ Mfr. model# ~~~~~.

thanks
Ian

It is craftsman Power bolt-out #52168

I have that same set and used them with )mostly) success. I still had one that turned into a near disaster..... But, I was due......

Cheers