Danger! Amateur 2.0 Rebuild Commencing

[La Voce]

I was thinking $600 for a professionally remanufactured head was hard to beat. The new parts that come on a reman head from Centerline or IAP would cost me around $230, then I'd have to pay a head shop to do the rest. Even at a modest shop rate of say $75/hr, four hours of labor and now it's a wash. But, you have inspired me to take the head in to a local shop first and at least ask what they think.

[BattleBug]

This past spring I had a semi-local machine shop redo my cyl head with SS big valves & HP springs. I did the disassembly work to include the lower exhaust studs. They cleaned, pressure tested, shaved, installed new guides/seals, and angled the seats to match the new valves. I sourced the parts at $230 on eBay; the machine work brought the cost up to almost what a stock reman head would be. Hindsight being 20/20 I would've gone with Centerline/IAP for less than an extra Ben Franklin. Oh yeah, now I remember why I didn't do that!! The exorbitant $350 core charge.

Paul

[alfaparticle]

I have a Richard Jemison prepared head on my Spider and I am very happy with it. I had previous head work done by a fairly well known Alfa mechanic and I was disappointed with it.

[La Voce]

True Paul, I am assuming the entire core charge would be refunded, but admit I'm at their mercy and would have no choice but to accept a "sorry, your head is not rebuildable because of ____."

Alfaparticle may I ask what Richard charges and where he is located?

[alfaparticle]

Jim:
Richard -AlfaR7 is in Pensacola. I bought a head from him that had racing valve springs, was notched for high lift cams and had ported intakes, so the price that I paid for it would not be representative of a simple valve job. I thought that his charge was very reasonable for the work involved and the quality of the job. He also rebuilt a gearbox for me at a very reasonable cost.

[La Voce]

OK she's completely out and I am tearing her down. Prepping the engine bay for touch up paint.
I notice one of the six crank peen plugs is missing- wonder where it went? That probably was a contributor to my low oil pressure at idle?
Found a cam chain master link clip, some very small, thin and sometimes bunched curly aluminum shards, and a small flat piece of what appeares to be bearing or shim material in the oil pan sump, but no evidence of anything broken so far as I remove the crank caps and look at the bearings.
Also I notice that the six roll pins were installed to protrude about 2mm above the block instead of 2mm above the head gasket. When I lay the gasket beside them, the tops of the pins are flush with the top of the gasket. Is this a problem or leave them be?

[La Voce]

BTW, new oil pumps for an Alfetta are NLA at any of the usual US locations, tried Vicks, IAP, Centerline, Alfa Parts Berkley, etc. No luck. Highwood has them but at the exchange rate, it's about $400 incl. freight. I will keep the one I have and see how it goes.

[La Voce]

I did not mark the relative location of the engine flywheel before I removed it as the Haynes manual instructed. I looked for factory scribed alignment marks but nothing is apparent- what happens if I guess wrong and reinstall it in a different relative position?

[PSk]

Quote:

Originally Posted by La Voce I did not mark the relative location of the engine flywheel before I removed it as the Haynes manual instructed. I looked for factory scribed alignment marks but nothing is apparent- what happens if I guess wrong and reinstall it in a different relative position?

[danyl]

Now that brings up a really great question: Balancing a crank and flywheel together.

I've rebuild at least a dozen engines, but never an Alfa. Perhaps Alfa is different, but for the Mercedes, BMW, GMs, and Saabs I've rebuit, the crank and flywheel are NOT balanced together. They are each balanced by themselves. I haven't even seen a machine shop that routinely balances the entire assembly.

There's a lot of people who TALK about balancing the assembly, but has anyone here ever really done it?

A new flywheel and clutch almost never require a crank removal...

The most important reason to "mark" the position of the flywheel is to make certain that the VR TDC sensor is in the correct position. Gordon's HighPerformance store has the most impressive document with instructions for flywheel alignment if you forget to mark it.

[gigem75]

I've always been of the school of thought that all rotating assemblies are balanced together and put back together the same way they came apart. just my 02

[PSk]

Quote:

Originally Posted by gigem75 I've always been of the school of thought that all rotating assemblies are balanced together and put back together the same way they came apart. just my 02

[Clayton105]

Many moons ago, I worked in an engine reconditioning shop and would occasionally balance engines. I then left and was running an Alfa workshop and taking my bits to the shop I had worked for.

All of the components are balanced individually. It males absolutely no sense to balance together. I have in fact work for a short time in an engine manufacturing plant (in the tool-makers section), and observed separate piles of cranks, flywheels etc...

In fact, I was told by this shop that the factory Alfa balancing was so good, that it was basically a waste of time doing it. But, most engine shops are MORE than happy to charge you for the "service". The fact that most engines are not as well balanced is not known to most shops until they do the work a few times.

Having said that, an engine shop will balance the crank, then add the flywheel (and balance that), then add the clutch (and balance that). Then mark them all so it all goes back together the same way.... Not really neccesary if the spigots are all true, but makes the customer think the shop is professional. The genuine Sachs clutchs originally installed on Alfas are one of the few clutches I have seen factory balanced.

As the cank is driven on the balancer by the nose, the front pulley is usually balanced seperately. Early nord engines (without a harmonic damper) were not balanced as there is only a very small rotational mass. On a few serious engines, I machined these true all over to negate any small imbalance.

I once supplied some light buttons to insert into the clutch (to simulate an installed clutch plate) when balancing the clutch assembly. The balancer dude could not wrap his head around why you had to do this.... Cant get good help anymore!

[La Voce]

In the reassembly ("rebuilding") section of the Haynes manual, it mentions checking that a scribe mark on the flywheel is aligned with the mark on the rear of the engine as a means of verifying you've correcty set up the mechanical engine timing. Sure enough, both marks were faint but there- and there's an obvious "v" notch cut into the top of the engine to bellhousing metal gasket as well. And, believe it or not, after setting up the engine timing, when I aligned the marks, I was very close to a set of holes for the flywheel bolts. I reinstalled the flywheel and I'm back in business.

[La Voce]

Alrighty, engine back together and reinstalled. She spins just fine but no spark- will troubleshoot tomorrow.