Start over on "new rebuild"?

[coopster]

Hi Wayne.
Bought your projects book, and the rebuild 911 engine book last week. Great reads, and great info. A bargain at $22.

My son-in-law bought a basket case 82 (literally, in pieces). So not knowing much about these vehicles, when he asked me for help, it is a chance to learn, plus I’ve always kinda wanted one.

Anyway, the guy he bought it from said he had machine work, etc done by “an aircraft mechanic”, and had put together the bottom end. Although having read thru your book, I’m wondering if we should re-do.

But first Q is (and a reason we’d have to disassemble anyway), is that the wrist pin bushings are gouged (2 of em). So I think we need to take them and have them either replaced or maybe reground? Your thoughts? There are no receipts for anything, not even the gasket kit he had.

Of course, we’ll need to do the tensioner and some other mods in your book.

Second up, is that although it appears that one set of cylinders has pistons inside of them, in a box – might be reasonable to expect that the pistons were kept with the respective cylinders – the rockers are just all in a box.

IIRC, your book says it is just as important or more on these engines to keep them with original pairings. And I still haven’t been able to locate the heads, (nor the cams to think about it) although they must be here somewhere. There’s no numbers on the cylinders either.

There are two sets of cylinders; the second set has no pistons that I’ve seen. I can’t tell if they’re the Alusil or Nikasil (whatever). The ‘paired’ set is non-magnetic (didn’t test the ‘spares’).

So with new rod bearings and wrist bushings, are the placements of pistons/cylinders a non-issue?
What would you do regarding the rocker arms? Just go with what we got?

It looks like there are some new (new looking) cylinder studs to be put on the exhaust side; there are none there now. And apparently the top rows are steel, although still attached. But some of those are pretty rusty /galled looking.

The “new” studs are only about 9 in count; there are also some black looking ones that have some sort of material on the threads, obviously been used.

Do you think the installed intake ones would be able to clean up sufficiently?
Probably safe to go with the “new” ones that are in the box for the exhaust?

Thanks in advance.

[Flat6pac]

You can tell the cylinders, the K/S alucil have 10 fins and the Mahle has 11 fins and are nikisil.
You cant guess what someone else has done so for piece of mind, open everything and start fresh.
Bruce

[Walt Fricke]

You can remove the two rods without splitting the case. After you have the busings replaced and honed to size (machine shop work basically), you will need new rod bolts, as the stock rod bolts are a one time use item. If I were stuck in the Sahara I'd reuse what you have, because the engine has not been run with them, but you aren't.

On the other hand, splitting the case isn't that much more work in either direction. You can verify that new bearings (rods and mains) were used. You will need new rod bolts (all 12), and a couple of dozen of the little round O rings for the case through bolts. You will need orange Loctite or some other case sealer anyway for the heads, so you will have that for resealing the case.

The non-magnetics are Alusil. There are various schools of thought about how to rebuild with Alusils. One theory is that you keep cylinder, piston, and especially rings together, and just put them back together. I.e., don't rering.

Another theory is that you can have the Alusils re-etched or something, rering, and go from there. Plus views in between the two. Do a search for "Alusil" and read what folks have thought about all this.

I'd use the pistons and cylinders which are sets, keeping them together. Makes no difference which spigot you put which into in the case.

Me, I'd not worry about the rockers. You can have them reground square (talk with cgarr or others), but the problem as Wayne poses it is that the cam lobes may not be square, and the rockers wear in to match any small angle on the lobes. You aren't going to want to fuss with having your cams reground or whatever. So I'd just put them back in and not worry about it.

What I would do is examine everything carefully - do the rockers have funny looking wear, or pitting? Same with the cams. If not, just put them back in. If yes, then consider what to do about that.

Dilivar head studs ought to be non-magnetic, or at least less magnetic than steel studs. Sounds like you may have some Dilivar replacements for the lower studs, which is why those are out (perhaps some had broken) and the tops are still in. Dilivars have gotten a bad rap, but I used some black coated head studs which were, per the shop, Dilivars back in the '80s when they were the thing to use. They are somewhat magnetic, so I wondered if they were the "fake Dilivars" we were warned about. But they have seen good service on several of my motors. As have some real Dilivars.

For an economy rebuild, I'd use these. Nine is an odd number, though. I'd be a bit leery of mixing stud types.

For a top drawer rebuild, I'd go Supertec. But that sounds a bit like overkill for what you think you have let yourself in for (guys with money burning holes in their pockets don't acquire basket case motors to rebuild themselves).

You could remove the top studs and have them polished to get the rust off. And if yours won' polish up nicely (because they have rust pits which won't polish off), used good ones should not be hard to come by. Regular steel studs ought to do fine on an SC

For that matter, you should be able to purchase new steel studs inexpensively, so you could get a full set and not agonize.

Or you could move to North Carolina (isn't it?) to be near Bruce, and haul the stuff over to his place and see what he thinks of it all. Just this year he did a series here or on the 911 forum on a quickie rebuild of a car he bought for a price so low it was a steal.

[Flat6pac]

Walt, youre too kind...
Bruce