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Symptom was way high oil pressure. Stuck relief piston will ruin the drive gear if the filter does not blow off first. It has to do with the designed gear loading, and as oil won't compress, if the gears are hard to turn from too much pressure, the softer bronze gear turns to brass dust, as it did.
 

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Discussion Starter #83
Oil analysis first 1000 miles on new motor
Here is my oil analysis. Nothing to worry about on the oil pump drive gear. Will check again next oil change.
 

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FWIW I've had the same problem. Oil pump bought from Classic Alfa and installed by an experienced Alfa Romeo engine builder.
After a while (8000 km?) the engine ran "reluctantly", the timing sounded retarded, I had difficulty picking up revs. And then during an uphill acceleration, there was an "expensive sound" and the engine died. This was june 2019.

It turned out that the brass gear wheel had been chewed - as discussed in this thread. I ordered a new pump from Classic Alfa, which is in my engine now, and I am expecting the worst ... after another 8000 km.

BTW: there is a Facebook Alfa 105 Giulia forum where this is also being discussed: https://www.facebook.com/groups/Giulia.Berlina/permalink/3006540492695318/
 

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My 5 eurocents: From engineering experience I think it is a matter of machining inaccuracy (ie bad quality). Properly machined gears will only have static forces on the "tooth surfaces". Ever so small inaccuracies will start the surfaces to grind - and that is the end of any gear. If machined properly, the gear should be able to withstand high oil pressure ...

Mine read 6 bar (on hi-quality STACK instrument) cold idle, 1.5-2 bar at hot idle, 5 bar at 5K rpm hot. High, but not overly high ... ?
 

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Gordon Raymond is the man to rebuild a pump. I'm not sure if he can help one of these new manufactured ones.
[/QUOTE]


Kudos to Gordon. In reading this thread the thought occurred to me that it might be prudent to use a "new" pump for parts and simply ship it and the old pump to Gordon so that the original gear can be swapped and a good, reliable pump built out of parts from two pumps. The problem, of course, is "pattern-parts" that may resemble oem but actually aren't in sometimes critical areas. We'll have to pay more but saving an expensive engine rebuild may make the extra money well worth the expense.
 

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...Mine read 6 bar (on hi-quality STACK instrument) cold idle, 1.5-2 bar at hot idle, 5 bar at 5K rpm hot. High, but not overly high ... ?


My 'new' oil pump reads 5 bar (on an electronic VDO instrument) cold idle, 1.5 bar at hot idle, 5 bar at 5000 rpm hot.
I felt this was a bit on the 'high' side, but it's been like that for 7 years now...


.
 

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Kudos to Gordon. In reading this thread the thought occurred to me that it might be prudent to use a "new" pump for parts and simply ship it and the old pump to Gordon so that the original gear can be swapped and a good, reliable pump built out of parts from two pumps. The problem, of course, is "pattern-parts" that may resemble oem but actually aren't in sometimes critical areas. We'll have to pay more but saving an expensive engine rebuild may make the extra money well worth the expense.[/QUOTE]

Agreed. I wonder where the vendor's (most of the usual suspects) would stand legally if it was discovered the pumps they had sold had directly contributed to engine failure? What has been the feedback received so far?

I rebuilt my original pump for my 2l engine and using 30w running in oil, the pressure has been fine. However, after 600 miles, I've now switched to VR1 which is 20w50, but the viscocity at low temps (centistrokes) is very high. I'm nervous of the effect on low temp oil pressures now.... Does anyone run (say) a 15w40 (with sufficient ZDDP)? Cold weather is not an issue (UK based).
 

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I rebuilt my original pump for my 2l engine and using 30w running in oil, the pressure has been fine. However, after 600 miles, I've now switched to VR1 which is 20w50, but the viscocity at low temps (centistrokes) is very high. I'm nervous of the effect on low temp oil pressures now.... Does anyone run (say) a 15w40 (with sufficient ZDDP)? Cold weather is not an issue (UK based).
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I've run VR1 20-50 in my Alfas for about as long as Osso has and had no problems at all. I'm sure you're concerned with main-seal leakage but Alfas seem to like VR1 20-50 just fine. On really cold mornings (well, 25F is cold here in Texas) I find it prudent to drive gently for a few miles to give the oil a chance to circulate and warm up. Beyond that, I've always given my Alfas a brief warm up and then just driven them normally. Last Fall my low milage built engine failed due to a cracked cylinder head---low oil pressure, de-tempered rings, the works . . . I was expecting to find a pretty much destroyed engine but when we took it apart all the internals were in perfect condition. We could have re-used the rod and main bearings and, particularly important, the pistons and liners were undamaged. I found a new head, we honed the liners, fitted new rings to the original Motronics and my new engine is now ready for a change to VR1.
 

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I build Alfa oil pumps to different clearances for use with different engine types and application. Race engines are different (obviously) than those built for street application, and FI engines have different useful power ranges that carburetor engines. Over time, Alfa pumps differed considerably with specific applications. Generally, 20-50 VR1 is just fine for Alfa applications where it does not sit below 50 degrees F, and some warm up is allowed. Look at it this way, the molecular size difference between mineral base and synthetic is that synthetic is about 50% smaller than mineral. Pumps need tighter clearances, and volume delivery must be a bit more in correctly assembled engines. Lubricity is greater with synthetic, but mineral fills clearances more easily.
I run 20-50 VR-1 in ALL my Alfa engines, street and race. I also build pumps for racers that use RACE synthetic, but these pumps cannot then be switched to mineral base as gear loading increases dramatically, and can result in pump and engine damage.
As a pump builder, there are way too many cases where I know of damage caused by either after-market pumps, or pumps of the incorrect type used "because it will fit". Then the owners contact me. That can be an expensive learning curve. My HOPE is that over time, quality after market helical geared pumps will reappear for the market. They will probably NOT be inexpensive! They will be a good basis for modification unlike those currently available, and as each day I'm gettin older, I'll have a bit less work!
Does this help anyone?
All the above represents my opinions from my own observations over time.
 

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Tooth profile is clearly different between "new" and OEM above. In my rebuilds, I only use OEM gears, as obviously those worked just fine for Alfa for more than 50 years. Is the alloy different? Who knows. The OEM gears were cast then jig machined. The new gears appear totally machine cut.
Early 750 and some 101 1300's have slightly different bronze gear profiles than later 101, 101-1600, 105 and 2L, yet those wore just as well as the later OEM gears. Common in OEM gears may be small metal-transfer-pits caused by slightly "off" pump gear set-up, with any light bind in rotation, as well as bronze gear lack of perfect concentricity with the main shaft centerline. I correct for this in my builds. Also NOT a mechanical engineer, or one that 100% understands the complexity of helical gear tooth profiles, I can say that with having looked at thousands of factory core pumps, disassembling, gauging components and rebuilding, original Alfa factory gears do NOT show the type of failures seen with todays crop of after-market pumps. There are other issues with many of these as well, as many of my engine builder customers can confirm.
This is ONLY my opinion from my own observations over many years.
 

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Discussion Starter #95
I sent an inquiring email to Tom at Classic Alfa asking if they have any issues. It is apparent it's not a vendor but rather a manufacturing issue with the "German" pumps that are sold by everyone. I took pains to ask with humility and respect and I hope he reads it that way. That was several days ago.

I'd say that if you have an engine you are assembling contact Gordon. If it's in the car and running I would suggest keeping an eye on the play of the rotor/shaft. Write it down and compare as the miles accumulate. The play will increase and if it does pull the motor or drop the pan. In my case it's pull the motor as I've got a Classic windage tray and two gaskets in the way. I did order 7mm bolts 5mm longer to allow for the extra gasket and tray. I'm also going to have my oil analyzed again in a thousand miles and compare to the first analysis I posted several posts back.

I'd also suggest checking timing as the miles go by. If the gear is wearing the spark scatter will be obvious. I have a feeling I'll be contacting Gordon sooner rather than later. That's all I've got. For now:)

(edit) that didn't take long.... I'd also suggest running a Wix oil filter. IMHO they are the best out there. If anyone knows of a better one please share, this is important!
 

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I see that the new pump gear has worn and could be due to incorrect machining or using different material than the original bronze gear. I look at both gears and the gear profiles are not the same. The material looks different and should be analyzed. I worked as a chemist/metallurgist for almost 40 years and failure analysis was part of my job. I would consult with Gordon Raymond about your pump problems.
 

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Mike,
It is a shame that you got off to a false start with the new motor after all the care and attention that you gave it. You will appreciate it even more when it is has a reliable oil pump.
 

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I sent an inquiring email to Tom at Classic Alfa asking if they have any issues. It is apparent it's not a vendor but rather a manufacturing issue with the "German" pumps that are sold by everyone.
I've refused to use the 'cheap' new pumps already ten years ago. Those are big crap. Only those from the OEM manufacturer are usable. But a lot of people don't want to pay twice the price tag of the 'cheap' ones.

I always prefer to rebuild and modify old OEM pumps over new pumps like Gordon recommends.
 

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Discussion Starter #99
Well considering Classic only sells one pump for my car and in 50 years of Alfas (although I did take a break in the middle) this is the first time I've had a problem it's not unreasonable to use from a reliable supplier what are considered good quality pumps. I'll know if it starts to wear and I can take action then and call Gordon.
 

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Discussion Starter #100
Time to contact Gordon. I pulled the dist cap off and there is massive play in the shaft. It's a 123 BT so there is no mechanical advance to worry about and the rotor can be rotated back and forth through several degrees. Much more so than the 1750 pump shaft I'm comparing it to. I imagine the Berlina pump will do the same thing but it only has a few hundred miles since I pulled the pan and put a new from Classic Alfa oil pump in it. I wrote Classic Alfa over a week ago and the silence is deafening. I'm not "after" them, I'd just like to see the problem fixed for everyone.
 
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