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71 Berlina 74 GTV 17 Giulia Q4
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Discussion Starter #1
Interesting failure. The vendor that sold me this pump (one of two) recalled it because he said the hole that holds the cotter pin that holds the relief spring was to low which would cause excessive oil pressure. I got it back and installed it in a new motor. I should have known something was up when the oil pressure gauge stayed pegged even when the oil was hot but silly me I figured it was the sending unit. I installed it with the 3 bolt tightening method and I could not detect any binding. I was just about to change the break in oil as I was approaching 1000 miles. 20w50
Any thoughts?
 

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Quite a few oil pumps from china have problems......

We need to know the name of the company selling these.
 

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As a builder of Oil pumps, I can't comment other than to say that high oil pressure did NOT cause that failure. There are 2 good 2L pumps currently being sold, BOTH built by one of Alfa's original pump builders. NEITHER are "cheap", and both are good. That said, much else of what is available is "none-too-good".
Don't take my word for it. Ask professional engine builders. (or ask Bill Gillham, Mike Besic and many others!)
 

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71 Berlina 74 GTV 17 Giulia Q4
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Discussion Starter #4
It appears he is no longer selling oil pumps so no need to identify any vendors in the SE US.
 

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What deteriorates on original pumps that requires them to be replaced by new ones?
 

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What deteriorates on original pumps that requires them to be replaced by new ones?
Gordon Raymond will have a better answer but like every other engine part, with wear the tolerances just get too big.
Gordon’s pumps are not cheap either but worth every penny.
 

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Richard Jemison
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pumps

Factory pumps are pretty bullet proof, not so some of the aftermarket pumps.

Even with some wear on the aluminum bodies around the outside of the gears, they are going to pump adequate levels of pressure for the low volume required in an Alfa engine. Typically closing the amount of end play on the gears will improve efficiency. That is easily done by removing the studs from the bottom housing and removing a few thousandths from the surface.

Gigem75, where did you source that pump? At Atlanta for the "Mity" Malcom, the owner of Apex Racing, had a similar failure of a new pump sourced from Spruel, on Sharon`s Giulietta SZ that they maintain. This was a new engine and she only got in 2 laps...
But the wear pattern makes me wonder not just about the alloy (brass not Bronze) but if the drive gear on the crank was put on backwards.??
 

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71 Berlina 74 GTV 17 Giulia Q4
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Discussion Starter #8
I'm just glad I had a Wix oil filter on. In all my years this is the first time I've pulled a pan with the motor in the car. First oil pump failure too. I can see slivers of bronze on the drive gear and on the sides of the front cover by the gear. My plan is to wash down with solvent from up top and get the remains out that way.
 

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71 Berlina 74 GTV 17 Giulia Q4
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Discussion Starter #9
The pump came from the same place as your friend's oil pump. The motor was fresh with less than a thousand miles on it. Ahhh shucks, now you're messing with me Richard. You did get me to check though I'll give you that. :)
 

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I did the same thing to an original pump in a 1600 motor. In my case, I think it was a result of improper installation. The pump went on after the front cover was attached. It was difficult to feel for binding. The most recent motor I assembled, I installed the pump on the front cover first.

Jim
San Antonio, TX
 

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As a builder of Oil pumps, I can't comment other than to say that high oil pressure did NOT cause that failure.
This begs the question of what did cause the abnormally high oil pressure. I have seen situations where the check valve sticks on an old pump, causing the cold oil pressure to be too high. But still high when hot? Perhaps it was just a bad sender.

the wear pattern makes me wonder not just about the alloy (brass not Bronze) but if the drive gear on the crank was put on backwards.??
In my limited experience, a gear installed backwards misses contacting the pump gear entirely. But maybe tolerances allow a backward drive gear to sometimes chew into the pump gear; still, in that circumstance, particularly with high oil pressure, I would expect the distributor timing to slip (e.g., the gears would skip teeth). I like the "cheap pump / bad alloy" theory.
 

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And remember the original vendor recalled the pump because the relief valve retainer hole was in the wrong place! That certainly would cause the pressure to remain too high. Then tells the customer don't worry, I don't sell those anymore!
Who else here got one of these?
And our pump rebuilder expert knows who makes the good pumps and who makes/sells the bad ones and will not say.....
I can't imagine how this is good for the community.
 

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Even with some wear on the aluminum bodies around the outside of the gears, they are going to pump adequate levels of pressure for the low volume required in an Alfa engine. Typically closing the amount of end play on the gears will improve efficiency. That is easily done by removing the studs from the bottom housing and removing a few thousandths from the surface.
I followed that advice from Richard when I rebuilt my motor 5 years ago and it has very good oil pressure. Jim K describes the same method in his book.

They don't make 'em like they used to :frown2:
 

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71 Berlina 74 GTV 17 Giulia Q4
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Discussion Starter #14 (Edited)
I thought Richard was talking about the drive gear on the crank. Since it can't be installed backwards on the crank (it can but I doubt it would even start) he was either pulling my leg or he was talking about the drive gear on the oil pump being installed backwards or upside down really by the manufacturer. The installing on the front cover first is suspect to me. Would it get by the slinger? It's diameter is almost as big as the OD of the front seal. Either way the factory method is to tighten the three mounting bolts gradually in sequence all the while checking for binding which is the way I do it. My final check is to move the oil pump shaft with a large screwdriver back and forth using the lash between the crank gear and the gear on the oil pump. It's not much but enough to get a feel for any binding.
 

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--ADMINISTRATOR--chiuso per ferie
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As a builder of Oil pumps, I can't comment other than to say that high oil pressure did NOT cause that failure. There are 2 good 2L pumps currently being sold, BOTH built by one of Alfa's original pump builders. NEITHER are "cheap", and both are good. That said, much else of what is available is "none-too-good".
Don't take my word for it. Ask professional engine builders. (or ask Bill Gillham, Mike Besic and many others!)
Gordon, the community is lucky to have someone with your expertise. Thank you for sharing your knowledge and experience with us.

It sounds like the bottom line is, if it's going in the engine, don't pinch pennies.:smile2:
 

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On some aftermarket pumps sent me, the relief valve upper body cylinder appears drilled with a wood auger! This DOES cause the piston to freeze in that cylinder as it might catch against a ridge or groove in the cylinder, causing high pressure.
As a rule with most Alfa parts that move or might cause whatever "system" failure, Brian's comment is 100% correct..."It sounds like the bottom line is, if it's going in the engine, don't pinch pennies."
 

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It is more than a case of pinching pennies. It is often a case of installing a part that was designed without the knowledge of the original design specs and/or manufactured by a company that does not have an adequate quality assurance program. Failure of such parts is not uncommon.
 
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71 Berlina 74 GTV 17 Giulia Q4
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Discussion Starter #18
I checked the play in the pump shaft on the other motor with the same pump and I pulled that motor just in time. A LOT of lash. Fortunately I had built "the one" with Alfaholics forged pistons, balanced crank, etc, windage tray, 30 deg big intake valves, RJ cams, MSD Streetfire ignition, 123 Bluetooth, Kent valve springs, and ported head where I went easy on the exhaust porting that was ready to go. BTW if anyone gets the Alfaholics forged pistons you will need to narrow the small end down to 21.99 mm so the small end will fit into the piston. A little tidbit they don't tell you on the website. But it's all good now and I'm very satisfied with the parts. Oh and a new oil pump from Classic Alfa. I also used their "race" timing chains and got the best fit ever on the lower one.
 

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And remember the original vendor recalled the pump because the relief valve retainer hole was in the wrong place! That certainly would cause the pressure to remain too high.
Oops, I had forgotten about that. OK, that explains the high oil pressure.

gigem75 said:
I thought Richard was talking about the drive gear on the crank. Since it can't be installed backwards on the crank (it can but I doubt it would even start)....
Right, that was my point about the gears not even touching if the one on the crankshaft is installed backward. Distributor won't turn, engine won't start, so no damage done.

.... or he was talking about the drive gear on the oil pump being installed backwards or upside down really by the manufacturer.
Got it. The gear on the oil pump may have been upside-down.
 

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71 Berlina 74 GTV 17 Giulia Q4
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Discussion Starter #20
With the benefit of 20/20 hindsight I now know what the whirring sound is that I heard. At first I thought it was the spica belt cogs since it sounded like a fast bicycle with playing cards taped to the fender. I never could track it down and pretty much ignored it. Now I know it was the oil pump. I also compared the spring to a stock factory pump and it is about 7mm shorter and has fewer coils. It also feels stiffer but can't say how much. Bottom line is that if you hear something that sounds like cards on a bicycle and you just put a new oil pump in that was cheaper than average (under 200) stop!
 
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