One of those days

[Ian Fulton]

It was raining the other day and I was Bored. What better than to adjust the valves on the Porsche. This had not been done for approx 12 months so this was a good opportunity. But it soon turned to well almost disaster. Look whatwas found after the first exhaust valve cover was removed. A bl**dy broken head stud
There is no other option here that to drop the engine and replace this/all studs. By the way this is a wide body turbo look alike 911 in Australia with 151000 km on the clock. I suspect the valves guides are also shot as oil consumption is about 1 litre per 1600 km. And there is some blue smoke on start up and when you pull up at a traffic light
Lets see what we discover

[Grady Clay]

Ian,
First, welcome to Pelican
You will find a lot of help here.
Sorry your first simple Pelican project turns into something so major.

Search Pelican and you will find a lot of info and support for easy recovering from this “almost disaster”.
Think positive as a good excuse to bring the ’87 M491 back closer to new.
This might also be an opportunity to upgrade the A/C.


Then you can address the wind noise.

Again, WELCOME.
Pictures please.

Best,
Grady

[Flat6pac]

Wellll, you at least dont have a long piece on the cap nut...
Bruce

[Ian Fulton]

Grady, Bruce.
Thanks for those replies. I have already update the air con, by installing a huge condenser in the rear whale tail and installing a modern evaporator and compressor. On a hot day here in Australia of 38-40 degrees C it is a pleasure to drive this 911.

This weekend I intend to drop the motor. I will document as I go and see what I am up for. Attached is a couple of photos

[Flat6pac]

And looking good..
Bruce

[Ian Fulton]

Well this weekend I am preparing to drop the engine on my 911 re the broken head stud. I have had my apprentice machinists/boilermakers produce 3 specialist tools, namely my version of the engine holding fixture to mount to a conventional engine stand, a lifting bar to literally lift the rear of the car up after the engine is dropped using an engine crane, and the Zed block for adjusting cam timing. The young lads did a fantastic job on these tools. The engine holding fixture I have never used before, along with the Zed block, but I am confident they will be fine. The lifting bar I have used before, and it works great and saves some time. I have attached a photo of these 3 devices. And I have just thought of another tool they have made which is the clutch aligning tool. I forgot about this one but it is in my garage somewhere.

[Daviboy]

Ian,
Thats weird almost exactly the same thing happened to me 3 weeks ago except for the rain. Dropped the lower valve covers to discover #4 rear most stub sheared. Dropped the motor replaced the studs and re-assembled. Just back from a short run this morning with wife and youngest daughter squished into the back to a nice little fresh produce market and she is running beautifully. Good luck with the project and those boys did a nice job of those tools

[Ian Fulton]

Sunday I dropped the engine out of my Porsche. Total time taken was 5 hours to have the motor/gearbox sitting on a pallet trolley. And all completed single handedly. The thing I did notice was the amount of oil present at number 2 &3 inlet valves once I had removed the intake manifolds. All other inlets looked dry, but is this a sign of worn valve guides? Given the mileage of 151,000km I suspect to find the valve guides are shot.
And the other thing I have discovered is it looks like I have the dreaded Alusil cylinders. Note this is only by counting the number of cooling fins on the cylinders. As I strip it down further this should become more evident

[Ian Fulton]

Started dismantling all engine components over the last week and this weekend.
All up the hours to date are 31 hours. During the last 7 days 26 hours were spent to get to the long block.
Included in the above is cleaning the heads and some measurement of valve guides/valves. The conclusion is that the guides are past their wear tolerance as I suspected

[Ian Fulton]

I have seen this question come up many times on this forum. Now I am faced with the same issue.
The arguments for include - your 80% of the way anyhow and you can address any other issues you may find.
Arguments against include extra cost.
One other reason for is as I understand it the cylinders and pistons need to be removed such that heat can be applied to the inside spigot where the cylinder is pushed into, to break the seal on the head bolts. To me once the cylinders and pistons are removed this is a great avenue for dirt to enter the lower engine crankcase, so for piece of mind it almost becomes a must. Another reason is I am unsure whether this engine has been apart before. There are no records of this in the files. My suspicions are that it hasn't given the evidence of minor oil leaks from a number of places around the crankcase. These leaks can be fixed by splitting.
Any comments?

[john walker's workshop]

once you're down to the case, it's about another hour to get it all apart, and more money for bearings, rod bolts, ramps, chains and whatever else looks tired.

[Ian Fulton]

Well the engine is totally stripped now. The intermediate bearings are showing copper, have to be replaced. Have sent the heads to a specialist in Australia to be rebuilt. Cylinders are Alusil as suspected. No wear evident by measurement or ring grooves etc and certainly within tolerance. Piston ring end gap is .026 inch on number one compression ring (limit is .031) and .027 inch on number 2 compression ring (limit .039). I have a real delema here. Do I re-ring and take the chance it works or do I reuse the existing nearly worn out rings. Measurement of main and rod journals show they are all in tolerance and journals look excellent. This car has obviously had regular servicing.
Orders for replacement parts has now been replaced. Now to clean and clean everything as this forum talks about. I am now at 40 hours approx. spent to date, excluding reading documenting etc

[Ian Fulton]

Well I spent all weekend cleaning and cleaning. I am quite happy with the way the crankcase came up, but it was a lot of effort.
Total time so far is now up to 60 hours

[Ian Fulton]

My initial parts order consisted of cylinder gasket kit, cam line replacements, 993 head studs, and sheet metal hardware.
I now realize I require more items including solid return tubes, chain ramps, flywheel bolts, intermediate shaft bearings, rocker shaft seals, case through bolt o-rings and ARP rod bolts.
These are just items for a basic rebuild. I hope I now have the lot. Is there a list anyone has, excluding items like bearings, pistons, cylinders etc.

[TibetanT]

Wow! Good job with cleaning your case, Ian. What did you use to do that? Method and cleaner type?

Anyway, yes there are many parts you will need for the successful rebuilding of your engine. Do you have Wayne's book? Wayne's book is very handy, as well as the factory manuals and Bentley.

I am enjoying this thread and look forward to the updates as the job progresses.

Just so you know, I am rebuilding a 1978 3.0L engine right now and have put over 120 hours into just cleaning parts. So, far I am only about 3/4 of the way with that part of it. I am a little over zealous when it comes to cleaning, but I am in no hurry since the 3.0L in the car is still running strong.

Good luck with your project!

[Tippy]

Originally Posted by TibetanT

Wow! Good job with cleaning your case, Ian. What did you use to do that? Method and cleaner type?

+1

Some of your studs look brand new too, almost like they were replated.

Do tell!!!

[Ian Fulton]

Ed and Cory, thank you for the replies. Firstly I have no parts cleaner home made or otherwise and there is not one locally I could find to do cleaning. I tried engine degreasers (useless) carburettor and brake cleaners (OK) petrol (known as gasoline in the states) great for external grease or caked on oil. Finally settled on POR-15 Marine Clean diluted 1:1 with hot water. It is recommended for engines and removes varnish back to bare aluminum with fantastic results. It took 3 goes followed by pressurized tap water and air dry. Machined surfaces I applied high strength paint remover & used a small wood chisel. Then polished the surfaces with 600 grit wet & dry using CRC (a spray lube). The bolts have just been wire brushed and rubbed up with wet and dry. Oil ways are squirted out liberally with Brake/carb cleaner followed by tap water then high air pressure many times.
I am happy with the result. Looks good. The proof will be an oil tight case on close up.

[Ian Fulton]

Ed, Further to my earlier reply. I am stunned how many hours cleaning you have spent to date. While I am only early into it I fully understand from reading the forum how cleanliness is so important. My project originally started as a snapped head stud. Now it is a full engine strip down. I want my baby back on the road again as quick as possible. I have limited funds but always thought I would track the costs and the hours spent. By the way i still have a lot of cleaning to go while I wait for head repairs parts etc. Do you have any photos of your hours of toil?

[billybek]

Oh no!
Don't track the cost!

Looks like everything is going well.
Interesting thread/pictures and documentation.
Have you decided to re use the Alusils?

[lindy 911]

I spent about two hours a side on my case. Some, I guess, are easier than others.[