1979 Porsche 930 with 83 Euro Engine rebuild

[vascott01]

"First off many future thanks for any and all advice"


Intro
I have owned this car for the last 10 years, has 65k on the odometer, 41K when purchased. I have tracked it 10+x I think and it has ran like a champ. No major upgrades, pretty much stock 1979 chassis with a 83Euro 930 Engine. No problems other than basic oil changes. Until....


The reason: Coming home from a track event and the car started to run really rough (I should have pulled over) but I continued home since I had only 45 miles left. I had already had a bad weekend at the track as I went off and busted up the front corner panel, lower valence and fender..

Essentially my distributor had moved. The screw that held it in place came loose...Was not a fun ride home. I did not know the issue until The following day after I relaxed and looked under the hood. Poof set the timing and I was back in business. Continued to drive for several months on weekends running short errands and it just never felt right after.

Decided to do a compression test and sure enough cylinder 3 & 6 were losing 55%. Performed a leak down and test came back the same...

Decided...Time for an engine drop and let the madness begin.

I will not bore you with the tear down as anyone can take something apart. The question is can you put it all back together. Hopefully with my notes, pictures, books and my short term memory (Hence the reason for you all) I will be able to put Humpty Dumpty back together again.



What I have done so far:
1. Complete breakdown
2. Crank/flywheel/rods cleaned and rebalanced
3. Heads cleaned and new everything
4. New engine wiring harness
5. Purchased all stuff to get case back together minus stuff I can get at the local stores.
6. Case is coming back tomorrow. I wanted it cleaned and oil squirters tested and replaced if needed.



1st stage - Crank and Rod assembly



List of items on hand:
1. Plastigauge
2. new rod bearings
3. New OEM rod bolts and nuts
4. brand new Torque wrench 3/8
5. Assembly lube
6. cleaned and balanced crank/rods

Things to do prior to starting
Clean all parts again, Measure everything



Cheers for reading and will need your keen eye for additional input

[Strygaldwir]

One of the biggest items I think folks miss in the rebuild is the Oil (Oel?) pump. Particular attention should be given there. At minimum a rebuild. I replaced mine with a 964 pump.

Are you doing anything to cams and compression? Chain ramps? Chains? Folks are getting the coated bearing now adays? Did you have cylinders re-honed? re-treated?

(I have a 79 Euro with 79 Euro motor).

Good luck,

Keith

[vascott01]

Update

Finished putting the crank back together today. EPIC moment. I have officially begun my adventure...

Tested the clearance prior with the old bolts several times to verify. Plus this was a good chance to practice the torque method.

Many thanks to Proffighter for providing the OEM Torque settings.



OEM Rod Bolt Torque setting - 1983 930



The rods move on there own weight when I lay the crank on its side..Time to put it back in a bag for Stage 2 Case assembly. That will happen most likely in 2 weeks when I have enough time for a full day.

Thanks all..Cheers

[vascott01]

Originally Posted by Strygaldwir

One of the biggest items I think folks miss in the rebuild is the Oil (Oel?) pump. Particular attention should be given there. At minimum a rebuild. I replaced mine with a 964 pump.

Are you doing anything to cams and compression? Chain ramps? Chains? Folks are getting the coated bearing now adays? Did you have cylinders re-honed? re-treated?

(I have a 79 Euro with 79 Euro motor).

Good luck,

Keith

I did take apart the pump, cleaned and re-oiled. Everything looked fine.

Not sure I am going to do anything to the cams but I am open to opinions. I am no longer tracking this car and always enjoyed what I have...like I said I could be persuaded.

New chains and ramps have been purchased.

All new pistons and cylinders. Destroyed 2 pistons and took a huge chunk out of a cylinder that could not be serviced.

[vascott01]

Here is a photo of the bad cylinder

[vascott01]

Here are photo's of the bad Pistons #3 & #6

[Strygaldwir]

Ouch!

[Edelweiss]

Just in case - we can service mostly all cylinders.

Welding with the right Aluminium and coating with original Mahle Nikasil.

Best reg.

Dirk

[onboost]

Originally Posted by vascott01

Not sure I am going to do anything to the cams but I am open to opinions. I am no longer tracking this car and always enjoyed what I have...like I said I could be persuaded.

I think you would like the standard SC or 964 upgrade, helps a little with the off-boost grunt. Web-cam used to have a nice one that was just a bit more than an SC but not quite 964.. I had that in one of my cars and loved it.

[vascott01]

Status update

Well after countless weeks of cleaning, prepping, saving and researching. I decided today was the day to finally put my case back together. Went through all the motions and even cleaned the case again. Probably cleaned the case no less than 6 times and I also took it to Intersport to have the squirters tested and case cleaned.

Charlie was great and did not even charge me. Many thanks Charlie and intersport

Did things by the book and took my time..Then I sat back and marveled at my accomplishment. Wow I feel AWESOME....

THEN....I looked down

What do I see on the floor....Oil pump seal


WTF.... Grrr it must have fallen during while putting on the top case half.. Now I have to undo what I have worked so hard up to this point...I cracked the case and sure enough..


I so wanted to have this accomplished and sealed up for xmas...

Back to the drawing board...

More like time for several beers

[Amstaff]

I recently put my case together and this was one of my biggest fears. I checked everything and then double checked but still have the urge to take it back apart to make sure I didn't miss anything. I am certain that I didn't but until the engine fires and there are no problems I will still worry.

Good luck on the rest of your rebuild!

Tom

[Mitch1]

It's a good thing you saw it and it didn't roll under something. I used a little Dow Corning 111 on the oil pump seals and case and it seemed to help hold them in place. Every time I opened the case they were both seated. It was my fear as well. I watched and double checked as case closed to make sure they were ok. If you have a gear head friend or Porsche club member that might lend a second set of eyes and hands it's a huge help. I would also put through bolts in now without seals and go back later and add seals 1 by 1. If that technique is good enough for Ed Mayo, it's good enough for me.

[Strygaldwir]

Good to catch it now and not when you're firing up the engine and wondering why the low oil pressure.

Cheers,

Keith

[vascott01]

Hey all...

Been awhile about to start again..Just checking a few things before friends come over and add several sets of eyes so that I do not screw up again.

Trivial question

Flywheel torque spec for Flywheel bolts for a 1983 930

bolt says 12.9 (93010220600) 150Nm??

Thanks again...

Cheers