Dave's Rebuild

[QueensEng]

This is my first rebuild, and It's on a 1982 SC. I just sort of dove into it after doing months of research and hmming and hawing and I'm glad I did... I've found that the old owners mechanic jimmied the clutch cable so that it would run right down to the nub as shown in this photo:


I also live in Canada so I don't need to worry about emissions and have decided to backdate to SSI heat exchangers and a sport dual in/out exhaust because I enjoy being obnoxious.

So at this point I've gotten down to the crankcase and have decided not to split it as I found no metal shavings/flakes/fillings anywhere in the oil when I emptied it. I have a few photo's for you all to pour over and give me some feedback. I've found that I have Alusil, and I'm not sure what to do here but by the sounds of it I rolled snake eyes... there's a huge Porsche recycling facility a few short hours drive so I'm certain I can find spec Nikasil P&C's (but I'm cheap, which doesn't bode well with this project as I've heard) as well as all the other crummy parts that disintegrated from the previous owners miss treatment of this fine specimen.



that's on the crankcase, not sure if it's significant or common.



That's on one of my pistons (which fuels the fire of those who will undoubtedly be urging me to buy new P&C's)



"Hey pal, I you're cylinder's leaking into the crankcase...", is that what that photo tells me?





The sparkies also came out powdery white... does this mean I'm going to need to do a teardown/clean up of the fuel system?



That's where I'm at now... a few more steps: take out the Divilar exhaust-side head studs, commence battle with the filthy wretches that are the exhaust studs, and then clean up commences.

So Guru's of Pelican Parts. What says you?

[mca]

Split the case. You will be glad you did.

Enjoy the rebuild. It is a great experience!

[Flat6pac]

Everything looks like the business as usual. The case has oil stain in all the same places as all the others.
The dark inside the cylinders is oil stain not blowby. blowby is at the rings. If you have nikisil cylinders, just hone the cylinders and add new rings. Alucil you cant do anything with because they dont seat new rings.
Some new sealants and you wont have leakage between the heads and the cam carriers or the center line of the case. Any where you have oil soaking the paper gaskets add some loctite 471. It doesnt have to completely cover the gasket, just where the oil stands like the bottom of the chain boxes to the case and the chain box covers at the bottom.
Make sure your cam shaft O ring seal is seated properly
Remember, everyone is going to spend your money faster than you can make it

Bruce

[QueensEng]

Thanks Bruce, some sound advice... I'm going to try and find some used Nikasil P&C's still in spec, gonna be tough I think but I'll persevere.

[Eagledriver]

I have re-ringed alusil pistons in my race engine. There is a very long thread on this subject. Bottom line is that there is a chance that the rings won't seat but I think that chance is small and if you don't mind tearing your engine apart if it happens you can save alot of money. You must inspect the pistons and cylinders and measure them for wear.

-Andy

[JohnJL]

Those casting flash marks are normal.

[QueensEng]

Yeah I've come to the final conclusion that 4100 for brand new, or maybe half that for used P&C's just simply is not in the budget. I'll have a look at that thread thanks Andy. And to answer you no I have not a single qualm with tearing the engine down again... I plan on it next summer for a bottom end rebuild (my pistons will stay IN the cylinders on that teardown)

- Dave

[sabeo.m]

Originally Posted by mca

Split the case. You will be glad you did.

Enjoy the rebuild. It is a great experience!

+1

I agree with mca. Even though you see no evidence of internal ware, you may find some in a few months after your top end rebuild. Splitting the case is only a few more hours it's not that difficult, mating the case is where you need to be careful and diligent.

Sabeo's 80SC Engine Rebuild

[QueensEng]

Again, budgetary restrictions apply... I'm still a student. This is a summer project while I have a rented garage and working a 6-2:30 job. I'm going to re-ring my Alusil's because they're all in great shape, very little wear and have a guy in Toronto do up my heads with new guides/seats etc. I have a question about that too, he wants to ream me for $200 a head for the whole job PLUS the cost of any valves should I need them (which I don't from what I can tell) so 1200 CAD for the set, is this a little high or is it reasonable. I'm also getting backdated Dansk SS exchangers (or just used OEM if I wuss out when it comes to putting up the dough) and a sport 2 in/out from him so he should drop the price of that machine work should he not?

[docrodg]

1200 for a head job? hehehe... oh the dirty little jokes that brings to mind...

I know some people want to save a lot of money on rebuilds, some are my friends and they drive me nuts not saving a little more so the darn thing will run long enough to need to retighten the heads. But... if that is what you want...

Re-ringing alusil cylinders does not work, the rings will not seat and wear will also be abnormal. Plus that cylinder pic shows damage to the piston head. Go the the recycler.

If you have a spring compressor remove the valves and check the stems, seats, clearances, margins etc... If valves measure good try lapping them, if the seats will clean up with a little lapping and the valves are ok (measure the stems in at least 5 places) then check heads for flat and if ok there are 2 major machine operations not needed. Guides will probably need to be done tho. Do not skip getting the guides checked out, this can kill your engine quickly as the valves can overheat and the heads "melt" off.

Being you are in school if you set up a dial mic properly and do a little math (assuming that math is something you learned in school, besides beer math... number of kegs per hour per frat brother) you can determine guide wear by measuring the amount of "wiggle" in the valve stem at the top with the head just a little off the seat. Measure in line with the rocker arm as this is the thrust axis and greatest wear.

Cut back on the exhaust reman if you can put the money elsewhere. If the exist exhaust is ok you can get some of the rest of the stuff you need and replace the exhaust later. Or use a used system when you go get the pistons/cylinders from the recycler.

White stuff on plugs is hard to tell with all the additives these days, wait to rebuild the FI until you have the engine back together and running. Use new plugs and adjust as needed per factory specs, then run for a little while and do a clean cut-off so the plugs give you a good read, should not be bad, then check every 100 miles or so until you reach 500.

I would split the case, honestly, there could be other gremlins in there, like clogged oil passages, spun bearings, gizmo...

[QueensEng]

Thanks Docrodg,

I'll do the measurements on the valve's that's a great read, I can borrow a ring comp for a few days to do that. Measuring the wear on the valves shouldn't be too tough the way you described it either. As for the exhaust, it's pooched, fully... but I've come to the sound realization that I don't need SS and some decent '74 OEM's will do the trick nicely, I'm dead set on the Dansk muffler though. I'm not splitting the case for the reason that I'm leaving that job for next summer, I've already discovered various parts that need to be replaced I wasn't accounting for (obviously) so money is tight. Thanks for the advice though, I'll take all that I can get... this is one thing I plan on doing many, many times, I'm addicted to Porsche rebuilding.

[QueensEng]

So the heads have been sent to be redone, I didn't have enough time to take out the exhaust studs which is a drag but I'm going to have them drilled out with a CNC mill I have here at the machine shop and then chase the threads with a tap so I'm not heating and cooling the bejesus out of them after I have them totally re-done. I've got all the parts lined up from the Porsche recycler which include the heat exchangers, shroud, air directer, and various other tid bits. As per above, the clutch wheel was worn right down to the rivets which did some serious damage to the flywheel so I was wondering if I had enough meat left on it to grind'r down (photo below) or if I'd be better off buying a used and not so mangled flywheel from this recycler and get IT resurfaced. The photo may not do it much justice... if so apologies, in your best description what would qualify a flywheel fit to be resurfaced?

[Eagledriver]

Originally Posted by docrodg

Re-ringing alusil cylinders does not work, the rings will not seat and wear will also be abnormal. Plus that cylinder pic shows damage to the piston head. Go the the recycler.

...

So I guess I'm just imagining that mine worked and the other sets that people are using are imaginary as well.

The flywheel looks pretty bad. If you can find a shop to turn it you can try it but I would buy a new one. I bought a brand new one for about 250 dollars 2 years ago.

-Andy

[tom1394racing]

The flywheel should be checked for thickness and run-out to determine if it can be resurfaced.

[docrodg]

Tom is right, check thickness and runout with a micrometer and check to factory specs. If bad, a new one is better than used in this case. Also ensure the new one is good on runout when you get it.

[QueensEng]

Just picked up my used 1974 heat exchangers and the muffler he had there for me was the Dansk RSR which I didn't like... after listening to some sound clips of various mufflers though I was curious if anyone knew if the B&B SS dual in, dual 4.5 out are going to match to my heat exchangers (obviously the valance needs some modding)? The last thing I want is to go and spend $1000+ on a part that isn't going to work.