First Rebuild - 964

iamtheari · 09-19-2014, 09:40 AM

My 964 needs a clutch. I slipped a bit downslope and am thinking about doing a rebuild this winter. The engine has 164,000 miles, unknown history, and great leakdown numbers on my 2011 PPI except 14% on the #4 cylinder which they didn't bother to trace to a more specific source. If I do the rebuild, I plan to keep everything stock other than Supertec head studs/nuts because they are only $150 more than stock and guaranteed for life.

I have Wayne's engine rebuilding book, the workshop manual, and enough threads on this forum to figure out the differences in the 964 engine as it goes together. I will probably also pick up the $100 DVD available from Pelican. I am posting today to be sure I have all the right tools and dollars on hand so, when I start, I do not often find myself waiting a few weeks for tools to show up in the mail or panhandling. I likely won't start the project until at least November, possibly January.

I have a decent set of tools thanks in no small part to this car and the Cayenne. But of course there are a few that I'll need to pick up. In chronological order:

I will borrow my dad's ATV jack to get the engine out of the car, working with a floor jack and jack stands to get the car out of the way. I will need an engine stand and yoke to hold it while I work. Pelican says that the P201 yoke is temporary unavailable. I think it was pretty expensive even when it was in stock. Does anyone have a good recommendation for an affordable stand and yoke that will safely hold the 964 engine?

Next up: camshaft tools. What does the 964 require to remove, install, and time the cams? The workshop manual specifies a chain tensioner tool. It's a $700 tool from Pelican and you need two. What's a good alternative? Also, do PEL-TOL-P204 and PEL-TOL-P237 (chain sprocket holder and cam shaft securing bar) work on the 964?

Torque wrenches: Do I need a 1/4" drive wrench or can this be done properly with a 3/8"? I have a Snap-On 1/2" digital torque wrench for the big stuff but my 3/8" Craftsman is currently out of service and the engine probably deserves something better. I would prefer to spend $100 instead of $500 on this. I want to do the job right but without throwing away money. Wayne's book lists from 8 Nm (valve cover nuts) on up.

Do I need the flywheel seal installation tool? It's $130 from Pelican and seems unnecessary since I'm going to have the case split open.

On the specialty list are also the following:
Dial gauge and Z-block holder
TDC indicator
Stud remover/installer tool that will work on M8 and M10 studs
Ring compressor

Then there are the chemicals/consumables. The workshop manual refers to a few Loctite products that I'm not sure still exist. It seems like the following chemicals are currently available to cover this job:

Plastigage: to measure certain clearances
Loctite 574 case sealant
Loctite 271 thread locker
JB Weld epoxy to seal up certain parts of the case
Antiseize on certain fasteners (any particular compound to get?)
Black RTV for through-bolts
Curil-T sealant on certain gaskets
Assembly lube: Any particular brands that you recommend? I see Brad Penn makes one and their oils are famously good for the air-cooled Porsches.
Break-in oil: Brad Penn SAE30 and wait for a warm enough day to run it. And probably stick with non-synthetic oils going forward, just dealing with the reality that I can't get it locally. (The locally available oil that I've been using is Rotella T6.)

As far as machine shop work and replacement parts, I plan to do a leakdown test to more accurately guess whether I can keep my pistons and cylinders. I really hope not to spend $3500 on new ones. I do plan to have the head gasket machining done on this early 964 engine. I plan to have some polishing and valve grinding done. I have a quote for:
$1,000 - valve labor (disassembly, cleaning, resurface, install and hone new guides, 3-angle grind, grind valves to match, reassemble, set spring heights)
$113 - valve guides
$42 - guide seals
$540 - exhaust valves
$570 - intake valves (only if needed)
$504 - factory springs
$800 - machine heads and cylinders for sealing rings, price includes the rings

I'll replace the oil pressure and temperature senders and all of the gaskets in the various kits, plus the following:

Wrist pin circlips 999.178.009.004, 12 x $4.75 (surprised these are not in the kit as the workshop manual says to replace them every time, am I missing something?)
Oil return tube 901.107.351.01, 1 x $13.75 (I previously put in one expandable tube; is there any reason to replace the other 3 tubes?)
Power steering belt 964.147.187.03, 1 x $41.25 (mine is immaculate as of 18 months ago but it's convenient to swap while the engine is out)
Oil pressure safety spring 901.107.531.01, 1 x $3.25
Oil pressure relief spring 930.107.531.01, 1 x $4.00
Oil pressure safety and relief pistons 911.107.512.00, 2 x $12.25

All told, it looks like I'm in it for:

$4,000: parts including rebuilt starter and alternator, engine carrier reinforcement, heater blower bypass, spark plugs, clutch slave cylinder hose, ignition wire DIY kit, engine sound pad, clutch release bearing shaft kit, transmission shaft seal, axle bolts, rear wheel bearings, oil filters, oil drain plug sealing rings, a fuel filter, and a few valve cover gasket sets to get me through the break-in period

Plus a clutch, flywheel, slave cylinder, and associated parts. That's the original project and not part of this budget.

$500 in materials: sealants, oils, etc.

$1,000 in tools

$3,000 to the machine shop

Am I missing anything that should be budgeted for prior to tearing down the engine?

iamtheari · 09-20-2014, 08:00 AM

Another option is to do a less invasive top overhaul. Less opportunity for me to mess something up inside the crankcase or introduce oil leaks. I would still want to re-seal as much as I could, though, since the main motivator is to leak less oil. Can the through bolts be pulled and refreshed without upsetting the crankcase seam?

Flat6pac · 09-20-2014, 08:20 AM

If you don't take it all apart, you don't know what you own...
Bruceo

iamtheari · 09-20-2014, 01:25 PM

It's a matter of weighing that against the risk of making a rookie mistake inside the case that leads to knowing exactly what I have when it all blows up on me. I don't want to bite off more than I can chew. My philosophy is, if I can do it right, then I should do the whole engine because the bottom end is low hanging fruit once you take the top end off of it. But can I do it right?

RedCoupe · 09-20-2014, 03:16 PM

Ari, I also have an early 964 and am planning a complete engine overhaul this Fall. For quite some time, mine has been leaking copiously from a couple of through bolts, and it turns out that a serious of early 964's had mis-machined engine cases: the o-ring recess on one half of the case was machined too deep. The factory fix was to grind the thick part of the special washers a little bit to allow room to stuff a second o-ring on the through bolt on that side and that was enough to prevent leakage. For a while.

It would worthwhile to check your engine number to see if it is one of the engines with the problem. When I'm home tonight, I'll find the TSB and post the engine numbers of the problem engines and you can see if yours is included. My plan is to measure the extra-deep recesses and make up some special washers with a thicker middle area so that it will seal with just one o-ring on that side, as is proper sealing practice.

iamtheari · 09-20-2014, 05:53 PM

Is this your first rebuild? If not, I am curious to hear more about the first one to understand how intimidated I really should be. The advice on that varies wildly, from the advice from a homebrew beer book I once read ("Relax, don't worry, have a homebrew.") to the paranoid (as in Spinal Tap, being told that not only can you not touch the special guitar but you must not even look at it). So I don't know what the reality is and don't want to find out the hard way when I first try to fire it up and things explode.

Thanks in advance for posting the TSB info on the mis-machined case issue. I also would like to see photos of your solution when you get there, in case I have to do the same thing. A picture is really worth a thousand words when working on a car, I've found, although even sometimes a picture isn't enough for my modest intellect to figure out (see my thread about trying to find the access panel for the suspension pump over on the Cayenne forum...still searching for that one).

RedCoupe · 09-20-2014, 06:11 PM

Not my first rebuild by any stretch, but my first 964 rebuild. That being said, I have never been reluctant to try something new as long as I had really good information and the proper tools. Between this forum and the available literature, you will be well armed to do a good job. Once I have my engine apart and the correct and incorrect o-ring recesses measured, I plan on making quite a few special washers. I have a machinist who can produce the washers as well as have them heat treated, so if your case measures the same dimensions as mine, I can likely get you some as well.

iamtheari · 09-20-2014, 06:48 PM

That all assumes I can even find the right recess.

How do you plan to fasten the washer to the recess?

RedCoupe · 09-20-2014, 06:55 PM

Okay, here are the engine numbers that were listed in the bulletin as having the through-bolt problems: 1) manual transmission - 62L11289 through 62L11307 and 62L12581 through 62L12801; 2) Tiptronic - 62L51104 through 62L51140.

Ari, if your engine isn't in this list, you probably have dodged this bullet, but I still would carefully measure the depth of the o-ring recesses on each crankcase half just to be sure. According to the bulletin, the extra deep recesses and the double o-rings should be on the nut end of the through bolts. Let us know what you find when you check your engine serial number.

RedCoupe · 09-20-2014, 07:10 PM

Quote:

Originally Posted by iamtheari

That all assumes I can even find the right recess.

How do you plan to fasten the washer to the recess?

Unlike the 3.2 and earlier engines that had a flat boss on each end of the through bolts, the 3.6 engine has a recess in the crankcase on each end of the through bolts. The o-rings fit into the recesses and "stepped" washers press on the o-rings to squeeze them tightly against the bolt shanks and the recesses to prevent oil leaks. The new washers will simply replace the thinner washers that are currently already on the the nut end of the bolts. I have asked myself why they didn't do this in the first place rather than the "temporary fix" of grinding the washers thinner and stuffing in second o-rings. The only answer I can come up with is that the production of new, thicker washers would have caused delays in the assembly of the new Carrera 2's, and Porsche may have been under pressure by their dealers to meet production deadlines. And, the engines ran fine and didn't leak oil (yet).

iamtheari · 09-23-2014, 06:22 PM

Looks like I dodged that particular small bullet. My engine number is 62L05927. I'll try to remember to measure the recesses when I get to that point anyhow, though. Just because Porsche didn't document a mistake doesn't mean it didn't exist.

RedCoupe · 09-23-2014, 10:18 PM

I agree, measuring will confirm that you don't have the problem. Also, watch for double o-rings on one end of any through bolts instead of the normal single o-ring.

DSPTurtle · 09-26-2014, 09:20 PM

You can replace the through bolt orings one bolt at a time without splitting the bottom end if you decide to go that route.

RedCoupe · 09-27-2014, 05:33 AM

Quote:

Originally Posted by DSPTurtle

You can replace the through bolt orings one bolt at a time without splitting the bottom end if you decide to go that route.

True, but with 165k on the engine, I would want a look at the main bearings, intermediate shaft bearings and the oil pump if I already had the engine apart anyway.

iamtheari · 09-27-2014, 12:17 PM

That's kind of my thought. You have to do a topend to get to the through bolts. The parts and machine shop work price difference for a top vs full rebuild is about $1,000. So I may as well go all the way.

What I struggle with is that the parts, tools, and machine shop labor for head/valve and polishing work comes out to $11,000 give or take. And that's if I can reuse all my pistons and cylinders. Shouldn't I be able to hire the rebuild done professionally for that much?

RedCoupe · 09-27-2014, 02:40 PM

Quote:

Originally Posted by iamtheari

That's kind of my thought. You have to do a topend to get to the through bolts. The parts and machine shop work price difference for a top vs full rebuild is about $1,000. So I may as well go all the way.

What I struggle with is that the parts, tools, and machine shop labor for head/valve and polishing work comes out to $11,000 give or take. And that's if I can reuse all my pistons and cylinders. Shouldn't I be able to hire the rebuild done professionally for that much?

About the only savings that you would realize from a professional rebuild would be the cost of the specialty tools that you would be buying if you would DIY. You will be paying full retail for all the parts and machine shop charges plus the hourly rate of the engine builder. However, with the right shop you benefit from the experience and judgement of a pro and you can theoretically get the job done in a reasonable time frame instead of in whatever spare time you may or may not have.

iamtheari · 09-27-2014, 05:49 PM

It seems that people have paid less for a full rebuild than my DIY figures are coming to. Maybe I'm just reading old threads and the price for a professional rebuild has gone up since they were written.