87 Drop Top - Drop-n-Top End

[Smoove1010]

After many months of reading every drop post I could find, studying Bentley and Wayne's books, my first drop went very smoothly. Did it single handed, and there was never a nervous moment. Here's the obligatory snap-shot. Am I in the drop club now?


A few posts were especially helpful, for example, this checklist was essential - thanks boyt911sc - I left the fuel connections for last, and almost forgot'em.
First Engine Drop

I'm now a big fan of the "small drop" method described by Audi in the same thread as the one above:
First Engine Drop

I used just the one floor jack. In my case, the drop was about 3", and the side-to side method allowed for a very controlled lift-off. The tail shaft on the tranny hung up slightly, a little more tilt might have made that go more smoothly.

When I brought my engine stand home and rolled the base under the car to store it, I realized it would make stable base to roll the powertrain out. With some two-by lumber and foam to cushion my ss heat exchangers, it worked like a charm. No balancing act required.


These two threads provided additional inspiration:
The Begining
good night, and when you wake up you'll feel better

So while I did this "on my own," it really was a team effort - me and the forum. Thanks for the help!

Clutch pivot shaft pulled out easily, needle bearings were nicely greased, almost a shame to replace with bushings but replaced they will be. Tranny comes off today.

Glad this was caught in time:


The plan:
Typical top-end, inspect the rest and hope for the best-type project. Keep the while-you're-at-its at bay. Fuel lines, fuel injectors. Lots of cleaning. Use this thread to document the whole project (there are never too many project threads, right?) Get car back on the road by May 1st. Now that I know how do-able the drop is, I wouldn't mind going back every winter or two as needed.

Thanks in advance for all the consultation I'm going to need... Now to find a Porsche-savvy machine shop somewhere nearby to do the head work and other sundries...

GK

[bigel]

Nice work...I'm planning to do the same on my 87 Targa soon as well.

Good luck and may the Porsche gods smile upon your project...

[Bob Kontak]

Excellent!

See post #3 for a shop option.

Machine Shop In Cleveland. Help!

Get your flywheel refaced (if needed) and replace the main seal. Clutch & pressure plate, maybe?

The only thing that freaked me out with my top end DIY was re-installing the cams. When I torqued down the cam towers my cam would bind (would not spin with finger tips) unless I used baby steps (2 ft pounds at a time maybe) on the bolt pattern.

Cam timing is relatively easy. By no means scary. You can tweak the cam timing a wee bit to increase top or bottom end but read up on this. Wayne's book probably mentions it (don't know for sure) but Bruce Anderson's performance handbook talks of it. You dial the lift at overlap TDC at one end or the other of the factory lift tolerance spread vs dead middle of the range.

Enough rambling. Good luck and have fun.

[Smoove1010]

Lots of disassembly today. Big Happy Surprise - the clutch was replaced not long ago! I feel like I just made $1,000! Lots of meat on this disk, but it was dirty. The pressure plate cleaned right up with some brake cleaner and scotch brite.



The flywheel had similar discoloration, but is otherwise smooth, no scratches, grooves, etc. I'll scotch-brite and clean this too. Any thoughts as to whether its necessary or advisable to scuff or clean the disk surface?


I took the intake off as an assembly. Here it is flipped on its back looking submissive. It'll be easy to r/r the hoses with it in this position.



Got a peek at the intake valves. Though the valve stems look clean (must've been the Techron) three of the cylinders had a puddle of oil in them. I noticed the intake runner just below the throttle plate also had oil settled at the bottom. Here's a dry valve (cyl 3) and a wet valve (cyl 1) for a look - though dark, you can see the liquid at the bottom. Anyone have any wisdom on these valves or why there's oil in the intake?

Dry Cyl 3


Oily Cyl 1


Thanks for the well-wishes. More to come.
GK

[bigg61]

I am looking at some great photos of your drop project. Looks like success to me. Nice going son. Keep on keeping on. Makes me want to wrench on my van. Need more temperature first. ......Big G

[turbochris]

That's my Brother! I'm so happy to see you back to skinning your knuckles and getting grease everywhere! I miss the days when we worked together at Lamano's.

Anyway, you're doing great, LMK when you're ready to get away from all the monkey motion piston rod crankshaft junk!

You'll get me in the turns but not at the dragstrip!

My fast street ride

Chris

[wholio94112]

almost beyond a project just like yours...thanks for reminding me of the obligatory "leaning tower of pisa" dropped shot...as touristy as it seems, i want one, because i successfully got that engine down and out!!!regarding the oil, its gotta be failed rings that hopefully didnt score your cylinder walls like they did mine...good luck, enjoy, and never rule out a bead blaster from craigslist or HELL-bor freight becoming one of your arsenal!!!

[Smoove1010]

Progress this week, an hour at a time after dinner in the chilly garage. Per all the advice on this forum, fasteners and other bits for each component are going into labeled ziplocs, and I’m documenting the order of disassembly since, as we all know, “assembly is the reverse.”

Flywheel came off, but not before I tried to use a 6pt. bit in an impact wrench. One bolt buzzed off fine, the next one didn’t…


Fortunately, the proper 12pt. tool on a ½” breaker bar held squarely to the bolt got this one and the others out.

Visible oil weepage at the flywheel crank seal. I guess that’s why this is on the list of essential while-you’re-in-there replacement items.

Fan housing, shroud and harness were taken off in one piece. I’m being careful to avoid bending wiring (as advised in Wayne’s book) because of insulation made brittle by heat-cycles. I’ll disassemble later on for detailing.


While lifting the fan/shroud assembly off, I felt resistance and stopped. Here's why it's good to resist the urge to force things - I made a special note to remember to re-connect this hidden ground.


Unfortunately the nubs at the bottom of this omega clip crumbled. Anyone know of a source for this? Is it a dealer-item? I couldn’t find it in our host’s catalog.


Insulation on the speed and reference sensor wires is crumbling. Even though the car was running fine, PP forum wisdom is that crumbly=done, and the cheaper BMW substitutes are on the shopping list now. Here’s a pic and a link to discussion on that topic. Inexpensive Carrera Speed & Reference Sensor alternative?


However, as seen, the CHT wire looks nearly new, is perfectly intact and flexible. It’s the 14mm two-wire version and the integrated rubber grommets were supple. I'm thinking it may have been replaced at some point in the life of the car. What’s the consensus – keep or replace?

Engine stand bracket and adapter are mounted, and the whole thing is ready to be hoisted up to the stand. As shown, the universal bracket mounting arms are very beefy, and there are four bolts holding the arms to the adapter. The weak link seems to be the two transmission mounting studs that hold the engine to the adapter. Intuitively, this looks weak. Has anyone heard of or seen cases where these studs break, causing unintended engine drop?


Once I get over my accidental drop-fear and get this up on the stand, the exhaust will come off as will upper and lower valve covers and chain housing covers. I plan to put the z-block and dial indicator on it to do a cam-timing practice run. This will get me comfy with that procedure, and should give me a baseline “before” reading on the overlap. I found this link to a cam-timing video on this forum – a video is worth a thousand words:
N Fulljames cam timing.wmv - YouTube

More to come… GK

[Smoove1010]

We have lift-off - with the help of a borrowed come-along and chains attached to an overhead I-beam. My project is now solidly mounted on the stand, and this one is extremely stable - I'm wheeling this around the garage easily. I recommend something like this for anyone doing this job.


These HE's were my first investment in this car - I bought it knowing the originals were damaged. The stainless steel looks great, and since they were only installed last winter, no exhaust-stud drama. Had the whole system off in 20 minutes.



How's this for a gunk-filled exhaust port? Number 1 cylinder was the worst of them, but not by much.



I'm sure I'll be spending the rest of the weekend doing an exterior scrub to avoid dirt falling into the bores or chain housings. I tried Gunk degreaser - looks like scrubbing bubbles - it made a dent, but not a big one. WD40 seems to work OK, hot water and Purple Power also seems to work, but there's no getting around it, it's going to take lots of elbow grease.



Question - my engine oil cooler isn't leaking - should I replace the seals anyway as a "while you're in there?"

[80-911SC]

yes .. do the seals to the cooler even if it is dry as a bone ... also do the thermostat o-ring breather cover gasket and the pressure sender ....

[ozracer]

Nice works looks great inspiration

[Smoove1010]

Spent the day cleaning the top-side of the engine - here's an in-progress and an after look:





Mineral spirits did the job the best. I did have a gallon of "green" low-VOC mineral spirits that I bought last year by accident, and gave that a try too, but the results weren't great. The low VOC stuff is milky and thick, almost like using a thin waterless hand cleaner. I found that I needed the regular stuff to wash the parts clean after breaking it loose with the low VOC stuff. If I didn't have a gallon of the stuff to get rid of, I wouldn't be using it at all.

As you can see, I used an array of tools. The good-old Oral B did a good job in the nooks and crannies, the brass brush was my go-to tool.

Just had a look at NoYouRelax's thread - First Engine Drop of 2013? - he used a steam cleaner, and his results look great. I just might have to get myself one of those...

I'm hoping during the week to get the engine clean enough to open her up, do a cam-timing practice run, then get the heads, P's and C's off to a shop for a re-do and inspection. While they are being looked after, I'll get busy - with more cleaning...

GK

[Smoove1010]

Cleaning takes forever. This before-and-after took me between 45 mins and an hour. Mineral spirits seems to work best, but it's still laborious.


Lots of nooks and crannies in those lower rocker covers:



So, progress is slow, but it's still progress. Next step: get the rocker covers off, do a test cam-timing run, pop the heads, p's, and c's off and see what I got in there.

[Smoove1010]

Now that the garage reeks of paint thinner, this is all the cleaning I'll be doing for now. There's disassembly to do.


Rocker covers came off. This was looking up at me on cylinder 2:

Amazing how it reversed itself. I guess I'm joining the re-stud-club. I'll be using steel since I'm keeping it stock, street use only.

Spark plugs came out - here they are lined up in order. The PO's mechanic put these in about one year and 500 miles ago. Interesting choice of plugs. Interesting too how 4-6 look so fouled while 1-3 look clean.


Chain covers came off next. Used the P237 tool and a 19mm to break the cam bolts loose. Is the P237 supposed to fit the gear holes so tight? I needed to tap it into place with a hammer. Once seated, it felt good and solid against the force needed to break the bolt loose.

Took a cam timing practice run. Either I'm doing it wrong, or it's a lot easier than I thought. According to the books, I was looking for an overlap of 1.25mm (1.1-1.4) and found that the z1 notch had gone just past the parting line when the valve moved 1.25mm. Repeated the test and found that the left cam timing was retarded - overlap was 1.05. Took a crack at adjusting it, and got it to just slightly over 1.25 on the first try.


Right side timing was 1mm straight up. Took two tries to get to 1.25. It's all academic though since it's all coming apart, but now I feel confident when the time comes to do it for real. Since the cam timing was behind, I'm expecting peppier performance when I get this back together with the cams timed up proper.

Moving on - How does the travel on these tensioners look? I'm thinking I'm in for two new master-link timing chains. Am I wrong? Any life left in these? Perhaps the chain stretch caused the cam timing to fall behind?




Tensioners were removed. Compressing and pinning took a few minutes. Took the 3 bolts off each cam retaining plate, and wasn't sure how much force was OK to apply to pull the cam out. I took this post as an excuse to go for it with a big crowbar. Camshaft adjustment flange is stuck
Didn't feel very Porsche-y, but it worked.

Moved toward removing the rockers on the driver's side, but found that the housing was in the way of inserting a drift-pin to tap the first shaft out, so the housing was dislodged enough to tilt it to one side while I accessed the back of the cam tower.


Rockers and shafts all looking good so far - no galling, discoloration or grooving, just even, normal, smooth wear. Rockers feel snug on the shafts, just the slightest, barely perceptible wobble, and only when dry.

Next: Cams coming out, cam towers, heads and cylinders coming off.

[Smoove1010]

The top end is apart, the heads are waiting for a trip to the machine shop. Tonight's after-dinner activity: remove the P's and C's. Though I expect (at least) to re-ring, I attempted to take the P's and C's off as a unit just to see if I could do it. I sure couldn't, and I'll be darned if I can figure out how it's done. There seems to me to be no room at all between cylinders to position a drift and a hammer to tap the pin out. I'd love to know how it's possible to do this.

Regardless, the pistons and cylinders are out, and I'd be grateful for some opinions on these. I'm particularly concerned about what looks like evidence of the piston skirts rubbing the bottom inside of the bores:




Is this normal? The plan is to take these to the machine shop for some precision mic-ing before deciding what to do with them.

There was a faint shadow of some cross-hatch on these alusils, but mostly they were just very smooth. The rings on the pistons had clearly rotated since being installed - on one of the pistons the gaps on the rings were perfectly in line with each other!

In the mean time, I already know I'm in for bottom row headstud replacement - you can see the left bottom stud on cyl. 2 is broken here, along with my crusty-topped pistons:



But what about the top row on the left side of the engine? These are, apparently, steel studs, and they appear to be rusty -

Do these studs need replacing as well?

The big end of the connecting rods feels nice and snug on the crank, so I'm confident in leaving those as is, however, I'm not as thrilled by the appearance of the bushings at the piston end - there's visible wear there that I may have to deal with now. I might post pics later for some collective wisdom, but I've got a feeling I already know the answer.

I noticed inside the spigots for 2 and 3 what looks like evidence of blow-by - you can see it at the 11 o'clock position on 2, and along the left side of the spigot on 3. Have I guessed right on this?



I was indeed getting a lot of oil in the intake (pics posted near the start of the thread) and I was attributing at least some of that to blow-by, this seems to support that theory.

Thanks in advance for any and all opinions and observations,
GK

[Jcslocum]

I will help a fellow NY guy out here. I'm not a 911 engine expert by any means but I can offer the following input:

How does the travel on these tensioners look? I'm thinking I'm in for two new master-link timing chains. Am I wrong? Any life left in these? Perhaps the chain stretch caused the cam timing to fall behind?

I would replace the chains for sure and inspect the sprockets very closely for wear and odd tooth shape. The chains don't stretch, the rollers and pins wear letting the chain grow in length. The growth of the space between the rollers wears on the tooth side and will make them more pointy. If the chains need replacing, then I would change the sprockets too.

Regardless, the pistons and cylinders are out, and I'd be grateful for some opinions on these. I'm particularly concerned about what looks like evidence of the piston skirts rubbing the bottom inside of the bores:

Measuring is the only way to tell if the bores are OK, diameter and/or out of round. The skirts are there to do the rubbing. This is entirely normal and expected. They also need to be measured and inspected closely.

There was a faint shadow of some cross-hatch on these alusils, but mostly they were just very smooth. The rings on the pistons had clearly rotated since being installed - on one of the pistons the gaps on the rings were perfectly in line with each other!

Depending on the cylinders, they can be replated. Millennium in MI has done lots of cylinders for me, not Porsche cylinder tho. Ducati Cylinders which are Nickasil. Rings should not be rotating in the bore. They were probably lined up at assembly.

But what about the top row on the left side of the engine? These are, apparently, steel studs, and they appear to be rusty -

I would replace all of them. The pitting that rust creates is a spot where a crack can/will propagate from. Better to be safe than sorry on this item.

I noticed inside the spigots for 2 and 3 what looks like evidence of blow-by - you can see it at the 11 o'clock position on 2, and along the left side of the spigot on 3. Have I guessed right on this?

Blow by is only a reference to the rings, as the pressure in the combustion chamber passing the rings into the crankcase. The case on these engines actually runs a vacuum to keep the pressure low as there are pumping losses (power loss) when the air in the inside (behind the pistons) of the engine is compressed when the pistons go back and forth. What you are seeing, is an oil leak from the joint between the cylinder and the case.

I was indeed getting a lot of oil in the intake (pics posted near the start of the thread) and I was attributing at least some of that to blow-by, this seems to support that theory.

Oil in the intake is an issue with the valve guides and valve stem seals, not the piston rings. A new valve guide and valve stem fitted properly, will make a nice popping sound when you hold your finger over the hole and pull the valve out. There will be no wobble, side to side, of the valve in the bore of the guide. The oil you see on the valves and probably in the cylinder, is coming down the intake valve stem, onto the valve and then sucked into the cylinder and burned. If it's coming down the exhaust valve it just gets burned up in the exhaust or cat. Head rebuilding will solve these issues.

That's my .002 and I hope this helps.

[kodioneill]

There's a guy on the board that rents out the crankshaft seal installer for twenty bucks + shipping I would recommend using the proper tool for that. Do a search for rent seal installer.

[McLovin]

A thread for the ages! Thanks for taking the time to do this, it will be helpful to many.

How many miles are on the engine?

[hcoles]

Things look good.
Unless I missed what you were doing re. the fuel lines, you might consider sending to Bill Hippy in Florida. I understand he has moved to a bigger building and is setup and going again.

Yes, endless cleaning, but sort of forces you to get familiar with the parts.

[Smoove1010]

Hcoles: "Unless I missed what you were doing re. the fuel lines..."
I'm still weighing options on that, I've read just about all the fuel line threads and honestly haven't decided. There's a hydraulic hose place one town over that I may visit to see if they'll attempt a re-hose, at least I know what kind of crimps to look for thanks to this thread and others: New fuel hose busted-fire narrowly averted

McLovin: I don't know about the ages - there are many threads like mine that are already here. In each case, learning about the poster's thought process was the most interesting part, and the willingness to subject that to scrutiny in exchange for free, knowledgable and thoughtful advice seemed like a great way to document the project and learn more about these cars. Mine's got about 99k miles on it, and no service history, so I'm in a process of discovery.

Kodioneill - thanks for the tip, I'm going to check that out.

Jslocum - thanks for the thoughts. I'm on the fence about the chains given feedback on other threads about new chains with old sprockets. J. Walker advised to leave them (in another thread) but if I have reason to split the case I'll go for new chains and gears/sprockets. I'm taking the p's and c's for evaluation and measuring to the shop that's doing the heads. I may take a couple of connecting rods to have the bushings and pins measured too.
I was focusing on the black "soot" deposit at the bottom of spigot 2 (at about 11 o'clock in the pic) as blow-by evidence. If that's not from blow-by, what could that be?
Wish me luck, I'm going to try to dislodge a headstud or two tonight...
Thanks again for the comments,
GK