Size does matter

Alfa V6 Engine Information

This page is to hold any specific information which was hard to find, and which might be useful to other people. This information relates to the 66301 engine, which I believe ran from 1994 to 1998, and was the early 24v version. The main differences seem to be that this version uses a y-shaped, Tsubaki timing belt tensioner; the water pump is different; and the oil pump is driven by the timing belt, rather than by a chain drive. The changes seem to have been to improve the reliability of the timing belt. The tensioner was redesigned and moved to replace the oil pump pully; this meant that the shape of the water pump had to be modified; and the oil pump drive moved internally.

Alfa Romeo 3.0 24v V6 Dimensions & Weights

When I was originally trying to choose an engine, I found it very hard to come by measurements, even rough ones. So this page is just to list some measurements in case anyone else needs them.

These measurements are taken on an engine without any ancilliaries (so no power steering pump, alternator, or air conditioning pump). These add considerably to the width of the whole assembly in the standard car. They were just done with a tape measure so will be accurate to around 10mm.

Measurement Value Comments
Width across the heads 545mm Taken at the rear of the engine
Width across the Cam belt pullies 565mm This is the widest point
Length 570mm From the front of the crank pulley to the rear of the clutch cover. Note that the throttle assembly, flexible inlet pipe and air flow sensor will add considerably to this, but is all on top of the engine.
Height 680mm Bottom of sump to the top of the plenum
Weight of Flywheel 8.0 Kg

Cylinder numbering and Firing order

          |1   2   3 |
Front     |          |     Flywheel
          |4   5   6 |

The Firing Order is 1-4-2-5-3-6; ie it "ripples" from front to back, plenum side to passenger side


Alfa Romeo 3.0 V6 24v engine rebuild manual (pdf) click here

Alfa Romeo 3.0 V6 12v engine rebuild manual (pdf) click here

Alfa 3.0 v6 24v Engine Rebuild

The strip down and rebuild is scattered across a number of pages, so I've indexed them here to make things easier.

Section What's in it
Head Removal Heads, Injectors, oil pump drive, inlet runner comparison, cam pullies
Block stripdown Crank Pully, flywheel...
Reconditioning Checking measurements, cleaning block, reconditioning oil pump, bore honing
Cleaning Pistons Cleaning the piston ring groves
Short Engine Rebuild Page 1 Checking bearing clearances, fitting crankshaft and cylinder liners
Short Engine Rebuild Page 2 Assembling pistons, fitting pistons, fuel pump, oil seals, sump
Cylinder Heads New cams, bigger valves
Waterpump inlet, paint Use of an older, 12v, inlet casting to give a front-entry for the radiator bottom hose. Plenum modification and painting.
Custom Flywheel, Clutch, Balancing Fitting the flywheel and clutch, and getting the assembly balanced. More painting, and why you should use a ring expander tool...
Checking valve-piston Clearance Timing in the cams, checking nothing binds
Custom Alternator Fitting Using a Denso alternator, building a custom bracket to mount it.
Cooling System Design and build of the cooling system, with diagrams! Heater circuit deleted. Custom Engine Stabiliser Rod to prevent the engine rocking and keep the cam pullies clear of the chassis.
Sump Modification Standard sump shortened to give ground clearance
Finalised Timing Procedure After doing it a number of times, here's my procedure for setting the cam timing.

Bolts, bearings and things

Item Size Grade / Part number Comments
Driveshaft Bolts M8x50 12.9 High Tensile These are for the lobro (bolt on) driveshafts from a XR4x4
Alfa v6 Main Bearings Red 0060568882 Bearings are sized into three categories, Red, Green and Blue - you should get the ones which match the crankshaft.
Alfa v6 Rod Big End Bearings Red 0060513381 Bearings are sized into three categories, Red, Green and Blue - you should get the ones which match the crankshaft.
Tsubaki Timing Belt Tensioner - 60584475 No longer available generally, though occasional stocks do appear. Picture
The Ferrari 360 used a pair of these, though obviously they cost twice as much for the same thing...
Timing Belt Tensioner Pulley 58mm diameter, 31mm width 60580235 Offset mounting bolt hole, and two extra holes. Note that there are similar looking bearings for later models, but they are a different size. Check the dimensions! Dimensions...Picture
Timing Belt Idler Pulley 68mm diameter 60603056 This part number is actually for later engines, I think they just changed supplier. But the sizes are all the same and can be used interchangeably. 2 are required.Picture
Timing Belt 68mm diameter 28mm wide, 174 teeth Made by Gates
Rocker Cover Gasket Kit Driver's Side (rear in original car) 60568808
OEM, main gasket
OEM, round covers for cam humps - later replaced with sealant
BGA Part No for kit containing both - seems no longer available
Rocker Cover Gasket Kit Passenger Side (front in original car) 60568809
OEM, main gasket
OEM, round covers for cam humps - later replaced with sealant
BGA Part No for kit containing both - seems no longer available
Crankshaft Bolt Socket 41mm, 3/4" drive   Commonly called a "hub nut" socket