986 3.2 home engine rebuild

[bg305]

Your work looks great, I can't wait to see how this comes out!

I just replaced the variocam guides / cam chains and chain tensioners (The 3 for the ims chain, and b1 and b2 ims to cam - I highly recommend changing them out if there are any signs of reduced tension on the chains (chain slap on startup, etc). While I was seeing some plastic in my oil filter it was a sudden chain noise and raspy? sound to the engine note that had me pulling everything apart. My variocam guides looked similar to yours but were still intact. I do believe the chain noise was because one of my tensioners was failing or had failed). My 01s had 50,300 mi on the clock when I took it apart earlier this year. I did not go as far as removing the heads as you are doing.

Couple of thoughts / questions reading your post.

1. you mention that you "redone all the soft touch paint" - does this mean you had the sport design option with the white / speckle finish? I used testors 1830MT on mine, came close.. but not all the way there.. I had a thread here: New headunit with usb and mic integration Any-rate, I was curious if you have the same which paint you used. In addition to a smuge on the double din that is driving me nuts there are spots on the center console where the original sport design paint has been worn away.. I want to take the console out and respray, but would like to find a closer paint match.

2. You mention the oil gunk in the variocam tensioner, lifters, etc.. I also noticed how "brown" your carrier and the top of the head is. Mine was not like this at all. No oil sludge at all.. I am curious what you find, do you think it is possible there might have been some intermix with coolant at point earlier in the cars life? I saw no sludge anywhere, my variocam tensioners were nice and clean (did not stop me from giving them a good cleaning anyway). And I replaced one questionable lifter.

Here is an image from my engine, 50k on the motor, but it is only 20k miles different.
This one is with the new chain / guides:


this one was taken right after I removed the first bank cover, had not removed anything yet.


BTW, I also snagged the fuel return line dropping the engine but on the ebrake cable.. broke the seals on my injectors and fuel was dripping out. Luckily just getting new seals and re-seating the injectors took care of it.

Your son looks like he is having a blast! I tried to get mine involved (only a year older, 12).. He came down once or twice, was curious about how everything worked, but did not seem motivated to stay with it We do get to share other hobbies though so I can't complain .

[OldManMo]

Originally Posted by bg305

Your work looks great, I can't wait to see how this comes out!

I just replaced the variocam guides / cam chains and chain tensioners (The 3 for the ims chain, and b1 and b2 ims to cam - I highly recommend changing them out if there are any signs of reduced tension on the chains (chain slap on startup, etc). While I was seeing some plastic in my oil filter it was a sudden chain noise and raspy? sound to the engine note that had me pulling everything apart. My variocam guides looked similar to yours but were still intact. I do believe the chain noise was because one of my tensioners was failing or had failed). My 01s had 50,300 mi on the clock when I took it apart earlier this year. I did not go as far as removing the heads as you are doing.

Couple of thoughts / questions reading your post.

1. you mention that you "redone all the soft touch paint" - does this mean you had the sport design option with the white / speckle finish? I used testors 1830MT on mine, came close.. but not all the way there.. I had a thread here: New headunit with usb and mic integration Any-rate, I was curious if you have the same which paint you used. In addition to a smuge on the double din that is driving me nuts there are spots on the center console where the original sport design paint has been worn away.. I want to take the console out and respray, but would like to find a closer paint match.

In terms of the soft touch paint, I had the rubbish finish (which was great when it was new) that turns into a gluey gooey gunk







I removed of each part, re-painted with black plastic paint then applied a new soft touch top coat that made them look an feel oooooooohhhhhhh, so nice. Can spend hours just gently stroking each plastic part and rubbing my face against it...velvet....erm....ok forget all that







I removed all plastics on the dash, doors, etc and gave them the same treatment



The top coat I used was this one and when it cures it is super tough as I had to sand a bit back which was near impossible but at the same time it was sooooooooo sooooofffffffttttttt and like velvet

[OldManMo]

Originally Posted by bg305

2. You mention the oil gunk in the variocam tensioner, lifters, etc.. I also noticed how "brown" your carrier and the top of the head is. Mine was not like this at all. No oil sludge at all.. I am curious what you find, do you think it is possible there might have been some intermix with coolant at point earlier in the cars life? I saw no sludge anywhere, my variocam tensioners were nice and clean (did not stop me from giving them a good cleaning anyway). And I replaced one questionable lifter.

I noticed that, mine all had this yellow almost like yellow passivate finish to everything. there was no suggestion at all of a coolant leak but the only thing I can think of is that an oil additive was added, something like a hydraulic lifter additive. In any case all that yellow came off in the degreaser with no resistance at all

[PaulE]

What did you use to clean up those pistons? I've got one souvenir piston from my engine before it was rebuilt. It's still on my workbench as it looks like your pistons before you cleaned them up. If I can get my old piston that clean, it will go from my workbench to my desk!

Are you going to check the cylinder bores for roundness, i.e., no ovalization?

Everything looks great!

[OldManMo]

Originally Posted by PaulE

What did you use to clean up those pistons? I've got one souvenir piston from my engine before it was rebuilt. It's still on my workbench as it looks like your pistons before you cleaned them up. If I can get my old piston that clean, it will go from my workbench to my desk!

Are you going to check the cylinder bores for roundness, i.e., no ovalization?

Everything looks great!

They got a blast with Carb Cleaner to get most of the oil off and soften the caked on crud. Then 10 mins in an ultrasonic bath with a degreaser at 65 deg C, then removed the piston rings, then another 10mins in the bath



Then soda blasted at 50 psi then 30 psi



They went back into the ultrasonic bath at 30 deg C wit a very mild carb ultrasonic cleaner and they came up like below.



I did start polishing them up with some autosol and a rotary felt pad and then read they are coated so didnt want to polish out the coating. Got into a panic at first as though I had to buy a whole new set of pistons (and still might do mind you) but from what I read they are alloy with an iron coating, so used a weak earth magnet to test the coating is still there and it was on crown and skirts as this weak little magnet was very happy staying on the pistons

Yes, once the casing are cleaned up I will check for roundness and magnaflux test for cracks. I prefer to work with clean components



casings need a good clean first as does everything else too

[OldManMo]

Ok, onto the home straight. At this point I have only the crank box and bank 2 on the engine stand.

BTW, before this point I realised I had the engine stand mounted across the two halves so I put the engine on the hoist, re-adjusted the stand so it would only be on bank 2 and then removed the bank 1 side. Forgot to mention this, so would have been far less hassle to get it right first.



So removed the end caps from pistons 4-6 and dropped them out carefully. then removed the last long bolt on the Bank 2 side, hooked up the engine hoist to four points on the crank box, lots of prayers and gentle coaxing and the crank box separated from the bank 2 half. Lifted up the crank box (with brown pants) and then set down on a trolley



Had a look into bank 2 half and looked ok, but wait...what the fanta is that in the top left corner, yep a nut, some rando nut, which looks like its been in there a while and defo not looking like its within the engine. I count everything I take off an bag it, so it is possible I dropped something while disassembly but very unlikely.



Next split the crankcase, very carefully. Its not really heavy but awkward shaped. Looking at crank journals and bearings, they were not too bad but not far off end of life.



I will need to take loads of measurements to check the crank to be sure but I was optimistic, then I reviewed my photos and my heart sank.



What are those marks, they looks like metal that has been stripped away!!!!! At this point it was late one night, I had just tested positive for covid and I thought sod that, if the crank is gone this car will be parted out, cannot justify an 5k cost on a new crank.

[OldManMo]

Fortunately the next day and in the sun, with a better photo I could see it was staining which was coming off with cleaning. The sprocket looked ok apart from some marking from the chain



Anyone know what is and is not acceptable here? Can the sprocket be rebuilt or would the crank lose its heat treat if it was?

[OldManMo]

Ok, parts all stripped down and bagged or waiting for cleaning.


I am going to look to get the crank box rebuilt first once I have taken measurements and polished. Aiming to complete this by Christmas. At the same time I will send the cases, sump and some other parts from the bottom end to be cleaned

Here is what I have ordered for this part of the rebuild

Oil Separator
(99610101000)

Main Crankshaft Bearing Shell Standard. Porsche 986 Boxster / 996 >>2001
(99610120510)

2 x thrust washer
(99610112952)

6 x splash valve
(99610101851)

Tensioner Blade. Porsche 996 1998-05 / Boxster / Cayman
(99610516555)

Tensioner Blade. Porsche 996 1998-05 / Boxster / Cayman
(99610516651)

6 x pan-head screw M 6 X 16
(99921800501)

Timing Chain. Porsche 996 / 986 / 987C / 997.1
(99610517158)

2 x Timing chain. Porsche 996 / 986 Boxster
(99610517753)

roll pin 6,0 X 16
(90009503101)

straight pin A 4,0 X 10
(90030202100)

14 x screw M 9 X 127
(99610111559)

[PaulE]

Cool stuff! You inspired me to purchase a can of carburetor cleaner, my souvenir piston from the rebuild of my 3.2 is soaking in it over the weekend. I'll see if I can get it close to how clean you got yours! But it still has the rings on and the wrist pin in.

[OldManMo]

Originally Posted by PaulE

Cool stuff! You inspired me to purchase a can of carburetor cleaner, my souvenir piston from the rebuild of my 3.2 is soaking in it over the weekend. I'll see if I can get it close to how clean you got yours! But it still has the rings on and the wrist pin in.

Awesome If you are going to have it for show, then some Autosol will bring everything up and stop the rings from rusting

I can honestly say that my ultrasonic bath and small media blaster (using soda or fine glass beads) are outstanding in bringing things back to a near new look. Yes, you need to take care to use the right chems/media and clean thoroughly after using media but there is so much info/videos on the net that it really is not rocket science.

I am considering upgrading my small media blasting cabinet and buying a full on vapour blasting cabinet

[PaulE]

Originally Posted by OldManMo

Awesome If you are going to have it for show, then some Autosol will bring everything up and stop the rings from rusting

I can honestly say that my ultrasonic bath and small media blaster (using soda or fine glass beads) are outstanding in bringing things back to a near new look. Yes, you need to take care to use the right chems/media and clean thoroughly after using media but there is so much info/videos on the net that it really is not rocket science.

I am considering upgrading my small media blasting cabinet and buying a full on vapour blasting cabinet

I saw a video on Facebook of an auto detailing place, they were using a device that used dry ice in some kind of pressure washer. I think it is called a dry ice blaster. They were treating the undersides and inner fenders of cars with it and the parts were looking like new when they sprayed them. Remember, you can never be too rich, too thin, have too much horsepower or too many tools!

[Newsguy]

There's an article in Pedro's Garage about that.
Freeze your Road Grime!

[OldManMo]

Originally Posted by Newsguy

There's an article in Pedro's Garage about that.
Freeze your Road Grime!

Wow, thanks for sharing the link. I want one of those machines. Not only the car but I will do my neighbours cars, my house, their house, in fact anything else I can find to clean lol

[paulofto]

It's called Dry Ice Blasting and has been around a long time in the metal working business. Here is a pretty good run down of what it is, how it works and what it is used for.

https://en.wikipedia.org/wiki/Dry-ice_blasting

The company I retired from is a primary supplier of the dry ice pellets to the industry.

[OldManMo]

This is one of my favourite parts of any rebuild, no matter what is being rebuilt. When parts start to arrive. For me, it really is like have lots of birthdays

Recently, we have 24 brand new, shiny lifters/tappets packed in oil



A nice new oil separator with new gaskets



And lots of other parts inc, new injectors, seals, bolts, screws, knock sensors, chains, guides, tensioner, etc. Its only a small portion and loads more on the way, but I like to buy things slowly and especially when I can gab a bargain. As with the injectors and lifters which I paid less than half the normal price for the same part.



Hopefully the parts I need to start the bearing carrier rebuild will turn up soon

[Homeoboxter]

Great thread, thanks for sharing! The two variocam units are completely different, they move the chain to the opposite side during the changover. After browsing many threads and taking apart mine for inspection my understanding is that mostly only one of them fails, the one that has the large greenish O-rings that are prone to disintegrate due to aging. I forgot which one it is, I have a thread on this topic somewhere. Theoretically if you remove that steel cover disc you can pull the piston and replace the faulty O-rings. It does not seem to be easy to do though, it requires machining, mill, lathe, etc. If you go down that route let us know how it worked out. When I was rebuilding mine I tested the variocam operation while spinning the engine on my bench and activating the solenoids, and both turned out good. I have a thread on this in show & tell.

Good pictures, keep them coming!

[OldManMo]

Originally Posted by Homeoboxter

Great thread, thanks for sharing! The two variocam units are completely different, they move the chain to the opposite side during the changover. After browsing many threads and taking apart mine for inspection my understanding is that mostly only one of them fails, the one that has the large greenish O-rings that are prone to disintegrate due to aging. I forgot which one it is, I have a thread on this topic somewhere. Theoretically if you remove that steel cover disc you can pull the piston and replace the faulty O-rings. It does not seem to be easy to do though, it requires machining, mill, lathe, etc. If you go down that route let us know how it worked out. When I was rebuilding mine I tested the variocam operation while spinning the engine on my bench and activating the solenoids, and both turned out good. I have a thread on this in show & tell.

Good pictures, keep them coming!

Awsm, thanks for sharing and I will definitely look up your thread.

I struggled to find any real description of the internals and also photos but lots of warnings and statements of “it can’t be done”, “non-serviceable” “cannot be refurbished” etc. I come from an engineering background and hearing that makes me think “really?” And makes me want to run an experiment to see why. Yes, once removed some parts cannot be reused, but with technology as it is today, such 3D-metal printing, CNC machines etc once we have a 3D model of the parts required then why cannot these non reusable parts be replaced? Maybe it’s cost, maybe it’s complexity, that’s the experiment I wish to run and I will share my observations not to encourage everyone not to replace with new Porsche parts but to share and document the observations for other

I have seen a European company that does produce reconditioned units so it must be possible

[palindrome]

Great thread! I'm subscribed.

[Radman]

Awesome thread. I'd love to rebuild a 3.4 for my Boxster but don't really have enough room. Maybe when both kids are out of the house.

[OldManMo]

And my last "part" arrived today so I can start my rebuild



Have started with the clean up of the bottom end and will start sharing those photos and experiences and lessons learnt