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Discussion Starter #1
I've decided to rebuild my 1600 Duetto motor myself. I have quite a bit of amateur mechanical automotive experience. I can change out, and fix just about anything on the outside of a motor. Clutches, water pumps, suspension parts, universal joints, turbochargers, timing belts etc., but I've never rebuilt a whole motor. I have a few mechanic friends, and of course all of you on the BB to help me through, so success is assured. I'll post a lot of photos, cuz we love pictures, and they may help other Alfisti with their rebuilds. I'll be asking a lot of questions.
The motor is already apart down to the bare block. The gasket surfaces are pretty much cleaned, as well as the liner seats. The first photos is of the liner seats for cylinders 1 &2. The second for 3 & 4. The seats, and the camfer for the O rings are smooth. The liners sit all the way down with zero protrusion above the head without the O ring. The seats were cleaned with a Scotch Brite pad. Do the seats look clean enough?
The crank shaft journals are smooth, and I can't feel any scratches when running a fingernail along the journals. I measured their diameters with my new Harbor Freight $20 vernier. All the mains diameters are 1/ 2.361", 2, 3, 4, and 5 are 2.360". All the connecting rod journals measure 1.968". All are within spec according to my books. Since all are in spec, and smooth, I don't see a need for any machine work. I know I should check again with Plastiguage. Do I do this before I order bearings? Pat Braden says in The Twin Cam Companion "Reassemble the rod and cap around crank with a piece of Plastiguage laid along the bearing axis". He doesn't mention installing a bearing, so I'm a bit confused.
 

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This will be fun !
I did the same on my Duetto a few years ago and it runs like a top :^) !!
If you can get a copy, use the factory engine manual instead of an aftermarket repair book. It will be so much easier and everything will go together easily.
One recomendation I have came from a learned BBer about camshafts.
Use a 10548 cam on the intake and the stock Veloce cam on the exhaust. Tighten up the valve clearances to .014 intake and .016 exhaust. This works great on my 1600 with much improved power from idle on up !
Randy
 

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Randy what is the cam number for the stock Veloce cam? I have some spare 10548s and I think the originals are 10502. I have to start thinking about the engine soon too. Tom, this is a very timely thread for me. Heaps of pics and commentary please!
 

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Stock Duetto cams are #105020320001
This combo ( with just a little port smoothing ) works fantastic with everything else stock.
 

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Discussion Starter #5
I ordered the following parts Wednesday
Main bearings Std.
Rod bearings Std.
Gasket Set
Thrust Washers crank, and timing gear
Lock Tabs for:
Rear Main
Con Rods
Fly Wheel
Cams
and a crank washer
Hope I've got it all.
 

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I would add a couple of items....
Special viton o rings and roll pins for the oil passages in the head gasket. The factory o rings will distort and leak at some point. And make sure you use the good Reinz head gasket too !
 

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Discussion Starter #7
I have a pair of 10548's installed in my head, ready to go. I can't wait to finish this rebuild to see how they go!!! I also have a set of 105020320001 out of a "69 SPICA motor, a lucky find because my car originally had 2000 cams, so I can go back to original or set them up like Randy's.
If you can get a copy, use the factory engine manual instead of an aftermarket repair book. It will be so much easier and everything will go together easily
A good friend of mine Emailed me copies. They're much better than the manuals I have. Now I just have to figure out how to download them so that they're easier to use.
 

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You can put them on a flash drive and have your local Kincos or Staples print them. They can even do them 2 sided and spiral bind them so it ends up like a real book !!
Oh, you do need to install the bearings to use Plastigauge !!
 

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Discussion Starter #9
I think I'll do that. Diane doesn't like the greasey finger prints on the computer screen from me trying to flip the pages.
 

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Discussion Starter #11
All the parts are in, The block, con. rods, crank shaft, and all the front timing gears, and chains, and the work area are cleaned. I bought Plastiguage, and I've borrowed an accurate scale. I'll start my checks this weekend.
 

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Discussion Starter #12
I started the rebuild today. First I aranged everything I needed. Bearings, Plastiguage, 17mm wrench, 17mm socket, and torque wrench, bearing caps, channel lock pliers with plastic covers, hammer, oil, ans assembly lube. I set the main bearings in the block matching the bearings with holes to the oil galleries in the block. Then carefully set the crank onto the bearings. Apply a strip of plastiguage on the crank journal. Put the bearings in their appropriate main caps, and install in order. The caps are stamped with the journal # starting with 1 at the front of the engine. Oil the threads, and torque to 35 ft/lbs starting with the middle cap. Remove the caps. They fit pretty tight on the guides, and I didn't have special tool AR######, so I bought a set of plastic covers for pliers at Sears. They cover the business end so you don't mar the part your trying to grab. Grab the top of the cap with the channel locks, and tap the pliers with a hammer. Don't move the crank. When the caps are off measure the Plastiguage with the paper scale provided. They should be between .001, and .0025 according to Pat Braden. Mine were a wide .002. I couldn't figure a good way to check the rod bearing clearance. No matter what I did they moved, and I couldn't get the Plastiguage to work.If the mains are Ok is it safe to assume that the rod bearing clearance is correct too? How do you check these?
 

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Excellent work !
Do the rods with the pistons installed in the block. That will keep them from moving.
 

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Randy what is the cam number for the stock Veloce cam? I have some spare 10548s and I think the originals are 10502. I have to start thinking about the engine soon too. Tom, this is a very timely thread for me. Heaps of pics and commentary please!
Hi Derek

I will send you a PM re this, as like Randy has suggested I am keen to try something on the 1600 I intend rebuilding for my Super, when hopefully Scott can send his spare motor over to me. Dave
 

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Discussion Starter #15
I sent the crank shaft to the shop for a polish. I just got it back today, and installed the main bearings. The bearings halves were already in place in the block from the oil gap measurement. I set the top half of the thrust washers in the #3 block journal with the oil grooves facing out towards the crank. The assembly lube held them in place, as I set the crank on the upper bearing halves. I started with the #3 bearing cap, installed the bearing, and lower thrust washers in the cap with the oil grooves facing out towards the crank. I pre lubed the bearings, and thrust washers, and set the assembled cap on the studs. I oiled the studs, and installed the washer, and nut, and tightened them just enough for the cap to seat. I did the same with #1,2, and 3, without the thrust washers of course.
#5, the rear cap has the cigarette seals, rear main seal, the split washers for the fly wheel, and on 1600 engines the slinger. I turned the motor on end and installed the split washers, and put a couple of fly wheel bolts in to hold them in place. I put the bearing in the cap, and pre lubed the bearing. Then I oiled the grooves in the block, and the bearing cap, that hold the cigarette seals. I also oiled the cigarette seals. Can't have too much oil! I put the cigarette seals in the cap with the ends extending below the bottom of the bearing cap, then slid the cap, and seals half way into the block (photo 1) . With the cap, and cigarette seal half way in I installed the slinger (a large washer on 1600s) and the rear main seal on the crank (Photo2&3). I then slid the cap, and cigarette seals down making sure the cigarette seals bottomed out in the block. Then installed the lock tabs, and nuts. After every thing was all together I torqued all the nuts to 35 ft. lbs, starting from the center cap.
 

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Discussion Starter #16
Do the rods with the pistons installed in the block. That will keep them from moving.
It was a lot easier Randy!! I temporally installed the pistons and liners without the liner O rings to plastiguage the con rod journals.
I also learned an important lesson about keeping every thing clean. There was a tiny piece of metal on the crank or bearing when I was measuring, and when I turned the crank it scored one of my brand new con rod bearings. I ordered a new set. I'm lucky it happened when it did, and I had to take it apart to get the crank polished. Now I clean, and inspect everything at every step!
 

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Man, shows you what one little bit of junk can do :^0
 

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Discussion Starter #18
I'll bet you thought I abandoned this thread. I've never torn a motor down to it's very last nut, and put it back together again, so the process kinda got in the way of my post.
After I got another set of bearings, and installed them it was time to install the pistons and connecting rods. I put a piston pin in each rod, and tried to move it around to check for wear. Everything was nice and tight. Then I installed the rings on the pistons. It was pretty straight forward. They have a top, and a bottom, as well as a particular sequence from top to bottom of the piston. I used Hastings Rings instead of the one supplied with the piston, and liner set. Their directions are easy to follow.
Put a circlip n one side of the piston making sure it's seated in the grove. put a con rod in the piston, and push the assembly lubed piston pin through till it seats against the circlip on the other side. Install the other circlip. On 1600 Duetto engines the position of the piston on the rod doesn't matter, I made sure the lettering on the top of the piston faced the numbered side of the rod. It just looked neater to me.
With the rings on it's time to install the pistons. I bought a ring compressor from Harbor Freight. Having never used one I tried to put a piston in the liner to make sure I knew what I was doing before I actually installed one. I oiled everything up with WD-40. Compressed the rings, put the bottom of the piston in the liner, and gave her a shove with the but end of a hammer. The oil scrapers went in, but the bottom compression ring caught on the liner. It felt kinda risky to me. Like I could break a ring. So here's how I installed the pistons in the liners. Pu an O ring on the liner. Oil the bottom of the liner where the O ring sits with WD-40. Slide the O ring down making sure it isn't twisted when it's seated. Spray the inside of the liner, and a piston with WD-40. Put a piston and rod into the bottom of the liner upside down. I used my fingers to compress the rings working towards the gap till the went into the liner staggering each ring as I seated them. I pushed them 3/4 of the way into the liner.
 

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Me too! Presuming there are no copyright issues, you could post it to yousendit.com or one of those file hosting sites?

Does the factory manual tell you to install the rear main seal before or after seating the rear main bearing cap? Braden's book says to install them concurrently, but I've gotten a lot of advice here that its best to install the seal once the cap is seated (ie, how oil seals are typically installed).

Nice work!
 
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