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Discussion Starter #1
I have heard that there was a bad batch of repro 2L oil pumps that were out there a few years ago. I got a new, unused oil pump with a batch of parts and trying to figure out if it might be from that lot.

Does anyone know the vendor or any markings that would identify such a pump?

Thanks.

--S
 

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I have heard that there was a bad batch of repro 2L oil pumps that were out there a few years ago. I got a new, unused oil pump with a batch of parts and trying to figure out if it might be from that lot.

Does anyone know the vendor or any markings that would identify such a pump?

Thanks.

--S
I think that it is better not to post negative comments about the vendor. The vendor is a solid supporter of the Alfa community and did the right thing by these pumps. They are no longer in inventory, and therefore, there is no need to warn anyone. If you want to message me where you bought yours, I'll let you know if that's the one that had the bad pumps.
 

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Relax.....he said that it came with a bunch of parts, so it could have traveled thru a few hands before him.
I bought a motor needing a rebuild and found one of those pumps. PO had rebuilt everything. Machine work, new pistons +liners and there was this shinny new oil pump. Bearings were toast with LOADS of metal shavings imbedded. Took the pump out and inside the pressure relief spring area was still loaded with shavings from machining. So I would say take it apart, clean and measure everything if you want to use yours.
 

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I believe that these bad pumps were sold by multiple vendors. You may be hard pressed to find a good new one. Look for the thread. There is a material of construction difference that may help identify what you have,
 

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Discussion Starter #5
Searched before, but think I finally found the thread. (I need to remember to use Google search instead of the bb search for these ambiguous topics.)

I like the idea of taking it apart and checking it out. Good call.
 

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Keeps me busy! Many agree as a bad pump trashes the whole engine.
 

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Discussion Starter #8
Rebuilding the made in Italy pump is surely better than installing any reproduction made pump
Yep - that is my inclination as well. But I'll be taking apart the repro just for fun and comparison as well. Interestingly, the original pump (74) has nil shaft end play, yet the new repro has a bit of end play. That sort of says it all to me.
 

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This thread makes me glad I kept my old Oil Pump. I'm sure it's original and even though the new seems to be working perfectly, its nice to know I have the Original, and can send it to Gordon if (and when) I decide to rebuild the engine.
 

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Discussion Starter #10
So went through the repro pump in question. All gear/shaft tolerances in spec, etc. Seems good. Reading here on the BB the "bad" pumps had identifiable marking of missing some webbing on the outside of the body between the relief valve and the lower half (pickup part) of the pump. The main problem with those pumps seemd to be in the manufacturing process where machine shavings were left in the pump. Mine was clean. It is marked with the part numbers 60544527 and 60568782.

At any rate figured I'd close this thread out in case useful to someone else in the future.
 

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Again, there are good and bad repo pumps out there. Our parts dealers cannot easily see if they have good or bad without disassembly, materials and tolerance checks. Are main shafts correctly hardened? How about idler gear pins? Are relief piston bores properly finished? Relief springs calibrated correctly at the right length? Most critical, are clearances correctly set?
Here's one that appeared yesterday. The upper outer axial clearance is more than 1/8th inch! How will that gear correctly mesh with the hardened crank gear? Buyer beware!!!
1621579
 

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Again, there are good and bad repo pumps out there. Our parts dealers cannot easily see if they have good or bad without disassembly, materials and tolerance checks. Are main shafts correctly hardened? How about idler gear pins? Are relief piston bores properly finished? Relief springs calibrated correctly at the right length? Most critical, are clearances correctly set?
Here's one that appeared yesterday. The upper outer axial clearance is more than 1/8th inch! How will that gear correctly mesh with the hardened crank gear? Buyer beware!!!
Can you show us how to check the drive gear?
 

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Factory pumps had a cast bronze gear that was jig machined. Installed on the main shaft some had gear wobble, so factory upper axial clearance tolerances were liberal to avoid main shaft up-down movement as it turned. Factory built pumps had .2 to .5mm upper outer axial clearance, pump upper body bush to bronze gear bottom. This pretty much centered the tooth contact with the crank driven gear. The leaf gauge measurement shown below will give you some idea.
HOWEVER, this is not the way this clearance is correctly set in pump builds. There are several other critical factors. After correcting pump crank driven gear centering issues on the main shaft, and correcting pump upper body main shaft fitting to the upper body, as well as uniforming drive and idler gears, the inner axial clearance, gear top to lower body deck is set as needed for both oil type used and pump application.
1621588

With this build it's .1mm A for a performance street engine running 20-50 mineral base oil. Once the drive gear is hydraulically reinstalled on the main shaft, I will have .2 mm clearance drive gear top to upper body lower flange. Thus, this pump assembled and running, will have .05 inner and .05 outer axial clearance. NOT the .203mm axial shown as the standard factory clearance below.
1621593

This is not a thread on pump building, so all this is just some details. However, if you see more than .5mm upper outer axial clearance, like the sample shown in my earlier post, you WILL have problems with that pump gear.
My pump customers all have photo commentaries of individual pump builds. Any one of them should have a good idea of how an oil pump is correctly built.
All the above is only from my own experience over many years.
 

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I have a used pump out of one of my previous engines that is a factory S2 type. The gap between the gear and the housing is .015". I think that it must have been like that from new. Is it out of spec?
 

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No. .015" is .38mm. Factory tolerance was .2 to .5 mm. It gets more interesting with 2L straight cut gear pumps as these were more economically manufactured using machine assembly. Main shaft was "stepped"..
1621610

... and gears had a seat cut into them that seated on the upper step, with a mechanical axial clearance setting rather than one set by human hands and a gauge, as on earlier helical gear pumps. These can be improved by tightening clearances somewhat, after matching other components as mentioned. It involves re-cutting the shaft seat in the drive gear.
 

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From previous threads about the repop pumps. I thought it was the thickness of the teeth on the drive gear that was wrong.
 

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Lots of stuff is wrong with the bad pumps Jim. The difference between a bad repo and good repo is hard to see unless you start measuring and checking tolerances. Some of the "studded Veloce Pump Replacements" are too horrible to discuss. Ask Bill Gillham. He has seen a few sent by customers.
 

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Discussion Starter #18
So just to narrow this to the topic - a standard stock-spec 105/115 repro oil pump like you would buy from Centerline, ClassicAlfa, etc.

Gordon - the specs above are what I have been looking for. Super useful! Attached is what I have found in factory Spider engine build manual, Braden and here on the BB. Nothing nearly as detailed as what you have posted above. Are your specs you note above in Alfa manuals or tech bulletins any place, or just what you have learned from all your work on pumps over the years?

If the BB tool allows me, I'll rename this thread to capture all the info above. Seems like a good reference one for posterity.
 

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My specs started out, years ago, maybe at Ausca as factory build specs, but then may have been changed, over the years, as I learned some tricks. Specifications differ for different pumps built for different applications, or different oil weight. For example, there never was a 750 Veloce pump that used a 9 tooth, 31mm tall gear set, yet here are two, the one in the foreground built for a Normale, with bronze idler gear, and the one in the background, for a Veloce, with a double steel 1750 gear set.
1621711
 

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Discussion Starter #20 (Edited)
So using my repro pump as an example for others, it meets all the clearance specs in the Alfa manual. So now for the specs on this thread:

Are main shafts correctly hardened? How about idler gear pins? Are relief piston bores properly finished? Relief springs calibrated correctly at the right length? Most critical, are clearances correctly set?
  1. I believe the heat mark in the attached picture indicates that the mainshaft has been hardened.
  2. No idea about the idler gear pins. Not sure how one would check without tearing everything completely apart.
  3. Relief piston bore is smooth and the piston slides nicely. So I think that would be a "yes".
  4. Is there spring length people should be looking for?
  5. The clearances are within Alfa spec and the brass drive gear to top of body is .38mm...so in spec.
Given above, would one consider this repro a good pump? Point is moot for me, because like PSk, I'd prefer to stick with OEM even it needs some work to get it back to snuff. But this is a good thorough thread for others in the future.
 

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