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Hello All,
Money IS an object and I want to spend it wisely on renewing the most important elements of a 100K mile old rebuild I did to my stock Giulia Spider Veloce in 1975. It is still running perfectly and not yet smoking, but I have in the past spun a rod bearing on a different car's 1750 motor and I don't want that fate for this one. The head has only 30K miles on its more recent valve job and the head gasket is holding fine, so I intend to leave it torqued down and work from below, while the car is on a lift. Please suggest any additional replacement parts or rebuilds that are not mentioned in the quick list below:

Remove sump, crank, rods and pistons, replace rings, shell bearings, thrust washers, rod bolts/nuts and wrist pins. I plan to re-use pistons and not even hone the liners, since they will remain torqued down under the head. Seals and engine mounts will be replaced, but I intend to leave the existing oil pump in place.

Remove trans and replace rubber rear mount, clutch disk and T/O bearing, leaving pressure plate and flywheel alone if surfaces appear serviceable. Trans needs front and rear seals but synchros are still good. Best 90 weight oil for 50K mile old giulia ribbed style synchros on refill?

New guibo donut, shaft bearing and rubber support collar, u joints and nuts/bolts at diff pinion, new diff seal.

The goal is to be efficient with choices so that minimal time and money are spent on items that are difficult or expensive, and that do not do enough to prevent catastrophic failure from the 100K+ miles this lower half of the engine and some other parts in the drive line have endured. Also, the convenience of the lift makes avoiding the extra work of pulling the engine very tempting to skip. This is a veloce with all the tight airbox and header clearances that make pulling the head or removing the entire engine possibly not worth doing at this time.

Please suggest better approaches, tips, tricks, must-do component replacements/rebuilds, etc. I am thinking this through in advance and trying to benefit from the collective wisdom and experience of this forum. Thanks.
 

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If you remove pistons, you need to hone the liner's bores, as the new rings won't bed in ... why not leave pistons and rings alone and just replace the crank and rod bearings?

Also to remove the crank is a waste of time unless it measures badly and needs machining. If that is the case you will have to remove the gearbox ...


Or why not check oil pressure with an accurate gauge and if good, leave the engine alone.
Pete
 

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Are Alfa pistons removable from below? I'm not sure the webbing in the block won't interfere with them. But if they can be removed, how will you compress the rings when you re-insert them?

Can the crankshaft be removed without taking off the timing chain cover? I don't see how, as the lower timing chain is wrapped around the crank. But can you remove the timing chain cover without removing the head?

psk said:
If you remove pistons, you need to hone the liner's bores, as the new rings won't bed in.
Yup
 

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you cannot work from below and leave the engine in place. Not for the job described. You make life so much easier if not making the job possible in the first place by taking the engine out, if only because the box is going to be taken of anyway. . You cannot remove pistons from below if I am correct, and if you will not get them back in I am afraid.
 

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The amount of work you intend to perform (you ARE the mechanic?) is most easily performed with the engine or engine and transmission OUT of the car.
If you intend to ONLY refresh the engine bottom end, engine out, upside down, remove the sump, windage pump, windage tray. Clean those components looking for grey bearing material goo in the sump bottom. If its there (it will be) look for metal or metal chips, aluminum or steel.
Pull rod caps. Most will show wear, possibly to the copper in the shell. If you see copper, CLOSELY examine those crank journals for ridges that might indicate need of a crank regrind. #4 rod may show most wear. Disassemble back to front.
At any point where you see crank journal wear, you WILL need a complete disassembly to remove front cover.
Pull the main caps and look at the journals the same way. Here I start with #4, #5 being a problem as it has both the cigarette seals and retains the rear oil seal. The mains usually show most wear on the bottom shell. Again, copper showing, you better look close at that journal.
If none show copper, you can replace #4-3-2&1 plus the thrust washers (usually unnecessary) with the crank in place. Same with rod bearings unless you let a rod nick the naked crank journal (use shop rags).
This was done, engine in race-car, by most Alfa racers years ago at the track. I used to do it on my 1300 101 racer, car on the open bottom trailer. I started with rods, and only checked mains if i found worn rod shells. I would not pull the oil pump bottom UNLESS there was copper showing. For the oil pump, I would just replace the relief valve spring with new, and rotate the relief piston 1/4 turn when checking bearings and clearances "at-the-track".
This approach allows examination with minimal disassembly / reassembly. Being old now, I strongly prefer the engine on a stand, or upside down on cardboard for this check.
Odds are better than 50/50 you WILL need a complete disassembly at 100,000 miles.
This is ONLY my opinion from my own experiences over many years.
 
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Richard Jemison
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Refreshing the lower end

I disagree with earlier post.

You say the engine is running fine. And only 30K since the last build. Without cause, why do this?

Typically the only bearings to be concerned with are the rod bearings, but the mains can be inspected other than #1 & #5 as the crank needs to be held in place. If the main bearing isn`t leaking why pull the trans?

I do an "in-frame" on the race car when I think it needs checking with the block in the car. To get to where the guts are accessible you will need to remove the motor mount bolts & nuts holding these to the chassis. Then raise the motor using a jack under the pan or lift it from the top until you have reached the point the bell housing touches the top of the tunnel.
Insert small 2x4 wood blocks between the motor mounts & chassis.
Remove the lower "flat" pan and separate the oil pump pickup & lower body by removing the 4 nuts holding it to the upper housing. This will leave room to drop the upper pan and slide it forward and out.

Clean all the chassis under the block and cover the cross member with a clean cloth or towel.

Nor the rods are accessible and new bearings can be "Rolled into them after removing the old ones.
you can drop a couple of main bearings to look at the condition. Don`t change them unless you fins a REASON to change them.

It`s a hell of a lot easier than pulling every thing out. Timing will remain where it was and with new oil and filter it should be good to go another several years.
 
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