Aurel`s engine rebuild thread

[stevepaa]

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

[Aurel]

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

[stevepaa]

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?

[hcoles]

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.

[hcoles]

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

[Eagledriver]

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

[dcriss]

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.

[efhughes3]

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.

[Aurel]

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.


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?



Aurel

[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

[efhughes3]

Originally Posted by 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.

[Aurel]

Originally Posted by efhughes3

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.




Aurel

[OldTee]

Originally Posted by Aurel

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 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.

[OldTee]

Originally Posted by 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

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.

[hcoles]

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....

[TibetanT]

Subscribing for information purposes.

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

[shbop]

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.

[Michel J]

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,

Michel

[MatthewBrum]

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.

[304065]

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