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71 Berlina 74 GTV 17 Giulia Q4
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I just checked the timing on the Berlina and it's where it was when I put the replacement Classic Alfa oil pump in. That's good but I also don't have many miles on it either. When my pump failed it was telling me something was wrong before it quit. What happened was the timing changed and it was running erratically. So much so that I was going to check it when I got home. I almost made it. The motor quit about two miles from home. On the other car I caught it before it died. When the other new pump went in I sent a sample of the first oil change to Blackstone labs. I told them what had happened and to be on the lookout. When I got the results they said the copper levels were a little high but that was normal for a new rebuilt motor. I'm going to send another sample at the 2nd oil change at 2000 miles. Again the motor will quit before any catastrophic is done as long as you have a good oil filter. I use Wix and I'm not the only one who thinks they are excellent filters. By checking the timing frequently and checking the play in the oil pump shaft with the distributor out using a large flat head screwdriver you will have plenty of warning. As far as the already failed one I doubt any major damage has been done. I'll be very interested to know what Classic says. I doubt you are the only one who this has happened to and they must know this is a problem.
 
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Brass is a very soft metal. Your bearings are a lot harder metal. Get a Mobile-1 for equivalent filter. they are like 10 micron or smaller. let it flush out.

Are you sure it's brass and not bronze? maybe the gears were mis-aligned or not cut right, causing them to eat themselves. Even is they were softer brass, they probably should not have come apart like that if they were machined correctly I think.
 

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71 Berlina 74 GTV 17 Giulia Q4
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I corrected my metal. An oil analysis wouldn't list bronze or brass but rather copper and tin. Another possibility is the relief valve wasn't working as it should and the oil pressure was way high. High pressure would put extra load on the gear and with excessive load comes wear.
 

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In the above sticking relief valve, the filter seal will usually blow out before the gear loading ruins the crank driven pump gear.
 

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Discussion Starter #47
Here's how my problem developed:

About 100 miles ago, a high-speed miss developed around 3,000 RPM.

About 40 miles ago, I replaced plug wires; cap looked good and I was unable to pull off the rotor. Miss was not resolved.

Drove to mechanic (12 miles) - they replaced cap & rotor, but miss not resolved before they ran out of time. They also changed oil & filter.

I drove home to work on cosmetics over the weekend - car was now misfiring and backfiring from 1,000 RPM.

The following Monday I was 1/2 way back to mechanic - still missing, but now not backfiring - when engine abruptly shut down; no unusual noise or vibration, and green (oil pressure) light came on. My wife was following in her car and reported sparks and fireballs from under the car.

Back on the flatbed again. The tow driver actually remembered me from previous breakdowns . . . .

David OD
Laguna CA
 

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So no weird or low oil pressure behaviour?
As long as the engine was running, the oil pump had to be spinning. Yes, it was making a sloppy contact with its drive gear, resulting in the irregular timing that caused David's car to run poorly. But it was turning at the correct speed, so it would generate normal oil pressure. Once the oil pump gear degraded to the point where it stopped turning (or slipped a few teeth), the distributor stopped turning (or the timing was too far off) then the car stopped running. In other words, in this failure mode, the engine can't have no/low oil pressure and still be running.

No weird metal debris on the oil plug at that most recent oil change?
The oil plug has a magnet on it, so it's great at trapping iron or steel debris. But brass and bronze are non-magnetic so they wouldn't show up on the plug.

Still, the old oil would have had bronze bits floating in it that should have been visible. But if the mechanic just stuck a funnel under the oil pan and took out the plug, he probably didn't really see the old oil. And this is the shop that misdiagnosed the failing oil pump, installing a new cap and rotor to "fix" the problem.
 

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71 Berlina 74 GTV 17 Giulia Q4
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As I described that's exactly what happened to me. Nothing from the gear will stick to the oil plug and the small bits of brass will be in the bottom of the pan and some on the lower chain. I used plenty of air to blow off bits on the chain. Not getting everything clean was my biggest worry. I wasn't worried about anything in the bearings. Anything that got past the pickup screen would be caught by the filter. I would assume there would be a lot of very finely pulverized bits that if they did get by the filter would be so small to damage anything. I paid special attention to look for anything in the cam channels in the head and found nothing. btw the capacity of the oil in the head is about 400ml and always should be removed at an oil change. One of those big flavor injection cooking syringes works great to get it all out. It would be nice if the pump could be changed by just removing the bottom oil pan but alas no workie. I should be taken off though to clean all the bits out. That gasket is cheap as in inexpensive. Also, hi Gordon, I'm building one more motor and will use the pump you rebuilt in my "Dream" motor. Don't get to discouraged, heck on my first Alfa I got it with all the hoses off the head and just put hoses where the looked like they went. That didn't work out to well as I hooked a heater hose up to the crankcase ventilator fitting on the back of the motor and made it about a city block before the motor quit from the crankcase being filled with coolant. Your motor is fine. The only new pump I see anywhere other than the standard junk ones is at Alfaholics for 595GBP. Contact Gordon.
 

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71 Berlina 74 GTV 17 Giulia Q4
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I just read the Classic Alfa description of the pump they sell. They are probably going to tell you it was installed wrong. I use the method they call for and still had two fail.
 

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I just read the Classic Alfa description of the pump they sell. They are probably going to tell you it was installed wrong. I use the method they call for and still had two fail.
Did your's fail like David's - with the brass/bronze gear getting chewed up?

When you don't follow the procedure CA outlines, the failure mode is different. In that case, the steel shaft of the oil pump will fracture, usually where the hole is drilled to accept the roll pin that attaches the drive gear. I learned this lesson the hard way, with one of my early Alfa engine rebuilds, well before the internet made this information available.
 

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I don't quite understand why it's so difficult to make a decent aftermarket oil pump- even in China. Millions of new cars are made each year yet you almost never hear about oil pump failure anymore.

But it does make me glad I spent the extra money for a Gordon Rayman pump. Since I do not run a distributor, my motor would not automatically shut down in a stripped gear scenario. I'd just have to catch the low oil pressure.
 

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Hi there Jay, I'm going to respectfully disagree...
The oil pressure sender for the gauge is the very last thing in the oil pressure system. If as you guys are hypothesizing the brass/bronze bits from the oil pump gear are coursing through the entire oil system, putting the filter into bypass, ruining poor David's freshly installed bearings then there would be degradation in oil pressure, especially hot at idle, likely noticeable from when freshly rebuilt. I would think that as the filter went into bypass and back and forth depending on engine speed and such that the oil pressure gauge would move around with that as you would think system pressure may climb a bit when the filter goes into bypass.
Why disregard if there are extra bits on the oil drain plug? True gear material isn't magnetic, but the degrading bearings are, as well if the oil system has metal bits zooming around in it this may create extra wear in general. I would think that maybe second change after rebuild that the drain plug should be fairly spotless, anything else may cause a person to go hummmm...

Just my thoughts, feel free to disregard. I'm thinking if there were no other symptoms then poor David got lucky with the most recent oil change and that the filter never went into bypass so all detritus is trapped in the pan or one of the two oil filters. Well, and the little passage from pump to filter.

I thought you could change an oil pump from below with just the lower pan off. The mounting bolts are a super pain to get too and you have to do a gazillion rotations to seat the pump correctly but I though it was possible.

Cheers,
 

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71 Berlina 74 GTV 17 Giulia Q4
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My failures along with all the others noted in the thread I had were exactly like David's. I really don't see any gear material getting into the oil galleries and bearings. The filter going into bypass isn't going to happen. OK, anything is possible but in normal operation it isn't. I examined the oil that came out of the pan and head under moderate magnification and I didn't see anything unusual. But given anything is possible I'd say there is a 95% chance the bearings, etc are fine. It's not worth tearing the whole motor down. Taking #4 big end bearing off for inspection is a good idea though mainly for peace of mind.
 

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The filter going into bypass isn't going to happen. OK, anything is possible but in normal operation it isn't.
Can you be sure of that in a cheap, mass produced product made in who knows where?
 

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Hi there Jay, I'm going to respectfully disagree...The oil pressure sender for the gauge is the very last thing in the oil pressure system.
Sorry, I don't understand what you are respectfully disagreeing with.

I'll agree that the oil pressure sender for the gauge is the very last thing in the oil pressure system. So if the pump were to suddenly stop making pressure, there would be a delay equal to that pump-sender distance / the speed of sound in oil. That delay would probably divide out to a few hundred milliseconds. So how does that disprove something that I wrote?

I don't see how the engine could continue running if the distributor stopped turning or fell way out of phase after the oil pump gears began slipping. So I'm not seeing how the engine could have been damaged by running with low oil pressure.

Back in post #25, I conceded to Divotandtralee that the oil filter should remove the gear debris from the oil before it reached the bearings. The filter bypass issue was one I never tackled.

Why disregard if there are extra bits on the oil drain plug? True gear material isn't magnetic, but the degrading bearings are, as well if the oil system has metal bits zooming around in it this may create extra wear in general.
I guess you're saying that if the oil pump gear fragments really trashed the engine internals, there would be ferrous as well as non-ferrous debris in the oil. And the ferrous stuff would cling to the drain plug. Sure, I'll give you that. But is the converse true? That is, if there isn't ferrous debris on the drain plug, can David be certain that no crankshaft oil passages are blocked, no bearings are scored, ....? As gigem75 says in post #55 above, David or his mechanic can inspect some of the bearings while changing the pump. And he can cross his fingers that no oil passages are blocked (which yes, shouldn't happen if the oil filter didn't become completely clogged).
 

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71 Berlina 74 GTV 17 Giulia Q4
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Ed, I can't be sure of that in a cheaply made filter made who knows where. Maybe I shouldn't but I do work from where Alfa owners on the forum care about their cars and as such at least makes the attempt to buy quality oil filters. Oil pumps too. But surely you noticed the qualifier "ok anything is possible" which I put in just for you. :) :)
 

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I'd suggest looking in the cam galleys. Bunch of brass? Filter didn't work. No brass? Filter probably worked.

Were it me I'd also cut open the old filter and do a post-mortem, see what it caught.
 
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