Alfa Romeo Forums banner
1 - 9 of 9 Posts

· Premium Member
71 Berlina 74 GTV 17 Giulia Q4
Joined
·
6,815 Posts
not if it's on the firing stroke but if you just want tdc and not concerned with timing 4 is just as good as one
 

· Registered
Joined
·
293 Posts
Be careful if the distributor is off by 180 degrees. The shaft will fit onto the oil pump keyway with just a bit more than usual force, but if it's off, the oil pump shaft can snap off just about the drive gear. This happened to my '74 Spider several years ago. It's a simple task to pull the distributor and check, or to make it right, and all you'll have to do is swap the spark plug wires to their proper terminals on the cap.
 

· Registered
Joined
·
125 Posts
Discussion Starter · #5 ·
Re: Distributor/oil pump

I forgot to mention another possibility is that the oil pump wasn't installed in the correct orientation, and if that's the case, you're OK to leave it as-is.
How do you determine if the oil pump is positioned properly? Will it take a significant amount force to push the distributor tabs into the pump if it's not correct?
 

· Registered
Joined
·
293 Posts
The keyway in the pump shaft is slightly offset from the centerline, and sometimes it can be hard to see which way it's offset (it's dark and oily down there). The oil pump gear is has maybe 12 teeth, so it's possible to install it in 12 (if that's the correct number of teeth) different orientations. The key on the base of the distributor shaft is also offset, and it's also able to float back and forth a little bit. So, it's not very hard to push in the distributor 180-degrees off. I think the Bosch distributors are easier to install wrong than the Marelli. Anyway, you really need to have a picture, which I don't have handy, so maybe another member can post one or two for you. It doesn't really matter at all if the pump is installed differently from the spec, as long as you install the distributor correct, relative to the pump, and install the spark plug wires to match.
 

· Registered
Joined
·
4,335 Posts
If it was assembled 180 deg out you will have the following condition: With #1 cylinder at TDC on the firing stroke the rotor will be pointing aft rather than forward. Many (most) people will solve this by swapping the wires on the distributor cap but actually all you need to do is knock out the pin and rotate the dog on the end of the distributor 180 deg. That's the part in the picture above.

Of course if this is your case and the car is running okay and you want to set it up right you'll have to swap the plug wires back to their correct positions on the cap after rotating the dog.
 
1 - 9 of 9 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top